High Sierra Nevada Fossil Plants, Alpine County, Califoria

Journey above timberline to find 7 million year old leaves and petrified wood

Contents For: High Sierra Nevada Fossil Plants:

Text: The Field Trip

 Images: On-Site--High Sierra Fossil Plants

Images: On-Site--Calaveras Big Trees

Image: On Site--Mark Twain Cabin

Images: On-Site--Lygodium Gulch (Ione Fm.)

Images: On Site-Carson Pass Area

Images: On-Site--Valley Springs Fm.

Images: On-Site--Mehrten Fm.

Images: Disaster Peak Fm. Leaves

Images: Ione Fm-Valley Spring Fm. Leaves

Images: Carson Pass Pet. Wood-Leaf

Images: Mehrten Fm. Leaves

Images: Merhten Fm. Vertebrate Fossils

Image: Mehrten Fm. Coprolite

Links: My Guitar Playing Pages

Links: My Fossils-Related Pages

Links: Online USGS Papers

Link: Email Address

Field Trip To The High Sierra Fossil Plants

Those who would like to combine a trip to California's High Sierra Nevada wilderness with a visit to a fossil plant locality just might want to try the Mount Reba area of Alpine County. Here is a leaf-bearing site that dates from the late Miocene epoch, approximately 7 million years old. Some 14 species of ancient plants have been identified from the sedimentary-volcanic stratigraphic section of the Disaster Peak Formation, including specimens of cypress, Douglas-fir, evergreen live oak, tanbark oak, willow, and giant sequoia.

Today, the fossiliferous rocks lie at an elevation of 8,640 feet, but the plants preserved in them prove that 7 million years ago the site of deposition in that specific sector of the Sierra Nevada could not have been any higher than about 2,500 feet. This so-called Mount Reba Flora thus demonstrates that at least a lengthy segment of the central to southern Sierra Nevada has been uplifted thousands of feet by geologic forces during the past 7 million years, although sophisticated geophysical studies of regional rates of erosion and plate tectonics suggest that most of that mountain building has happened over the past three million years; on the other hand, rather recently amassed evidence indicates that the northern Sierra Nevada sector has apparently remained at approximately the same elevations seen today for at least 50 million years.

While the fossil locality is not difficult to find, be forewarned that a reliable four-wheel drive vehicle is required to reach the late Miocene botanic association. The "final assault" to the site is made along a rocky, rutty, and at times incredibly steep dirt path impassable in conventional vehicles. But the ultimate reward of such breathtaking High Sierran country, in addition to the opportunity to find some paleobotanically significant fossil leaves and petrified wood, is definitely worth the effort. Of course, prior to any excursion to the Mount Reba locality, always check with the local United States Forest Service officials to determine changes in collecting status.

A convenient place to begin a journey to the fossil-bearing site is Angels Camp in Calaveras County, along historic State Route 49. This is justifiably one of the more famous of the old gold mining communities in the Mother Lode, western Sierra foothills. In addition to sightseeing and souvenir hunting, a main attraction at Angels Camp is the yearly encounter with frogs.

The humorous Mark Twain short story "The Celebrated Jumping Frog of Calaveras County" (1865)--inspired by a story Mr. Clemens had heard in Angels Camp while spending 88 days in California's Gold Country during the winter of 1864-'65 (most of that time in a cabin at Jackass Hill, about 6 miles southeast of Angels Camp; from January 22 to February 23, 1865, Twain resided in Angels Camp)--is commemorated each year here with a jumping-frog contest, a traditional event that has had its share of unusual turns.

A number of years ago, for example, an ambitious individual keen on competition imported several two-and-a-half-foot-long carnivorous frogs from Africa and decided to enter them in the contest. Straight away, though, a regular shouting match broke out among the organizers over whether the monstrous amphibians should be permitted to compete. It was generally feared the African type would escape captivity and proceed to devour its smaller and less-aggressive cousins. Apparently siding with the alarmists, the California Department of Fish and Game initially would not even allow the man to bring his frog-whoppers into the Golden State.

But regulations were eventually relaxed. Not only did the amazing amphibians find their way into California (the owner gleefully showed them off to the media at every conceivable opportunity), but Calaveras County officials ruled amid escalating controversy that the animals could indeed complete.

Perhaps it was a foregone conclusion, but all this publicity brought in record crowds to the celebrated doings. Everybody wanted to see the fierce frogs in action. After all, how far could such a powerful creature leap? Rumor had it that the frogs regularly hopped across wide streams in their native land.

Well, when all was said and done, the results were rather disappointing for the highly touted amphibians. It turned out that the winner was an unassuming small-fry, some youngster's favorite regulation-sized frog. The African carnivores barely got off the launching pad. It was conjectured by the more conspiracy-minded that somebody had fed them too many bull frogs for breakfast.

Historic Angels Camp, which yielded vast fortunes in gold from Mother Lode veins during the mid to late 1800s, lies in the western foothills of the Sierra Nevada--the Snowy Range. Much of this Gold Rush country area is underlain by three famous Tertiary Period geologic rock formations: the middle Eocene Ione Formation (roughly 48 to 45 million years old), the late Oligocene to early Miocene Valley Springs Formation (dated by radiometric means at about 29 to 20 million years old in the Sierra foothills Mother Lode district) and the late middle Miocene to late Pliocene Mehrten Formation, dated through radiometric methodology at 11.6 to 2.59 million years old.

The older Ione Formation accumulated in floodplains, estuaries, lagoons, deltas, mashes-swamps, and shallow marine waters (based on extraordinarily rare occurrences of unquestioned marine mollusks) along the eastern shores of a vast inland sea during regionally sub-tropical middle Eocene times--a sea that had flooded, transgressed, what is now California's Great Central Valley during the earlier portions of the Eocene, approximately 53 million years ago.

In the vicinity of Ione (38 miles north of Angels Camp), that Ione sea left behind world-renowned commercial deposits of extraordinarily pure silica sand and high-grade kaolinite clays--in addition to extensive accumulations of the rare and valuable Montan Wax-rich lignite, which is mined commercially at only two places in the world--the other Montan Wax site is in Germany; lignite of course is classified as a type of low-grade coal whose alteration of original vegetation has proceeded further than in peat, but obviously not as great as anthracite coal. Montan Wax occurs quite rarely in the geologic record when the waxy substance which once protected the original plant leaves from extremes of climate did not deteriorate, but instead enriched the coal. Commercial applications for Montan Wax include polish, carbon paper, road construction, building, rubber, lubricating greases, fruit coating, water proofing and leather finishing. All of these mineral commodities--silica sands, kaolinite clays and Montan Wax-yielding liginites--have been mined in the Ione area by open-pit methods for many decades. As a matter of fact, today the Ione lignites remain California's only actively mined coal resources.

Not far from the community of Ione, on private property, lies an especially rich fossil leaf-bearing section of the middle Eocene Ione Formation that paleobotany aficionados affectionately call "Lygodium Gulch"--a site informally named in honor of the common well preserved specimens of a climbing fern encountered there--Lygodium kaulfussi (probably best known from its spectacularly abundant occurrences in the late early Eocene Green River Formation and the lower middle Eocene Bridger Formation of Utah, Wyoming, and Colorado), which most closely resembles the living American climbing fern Lygodium palmatum, now endemic to the US southeastern states (roughly the Appalachian territories down through the South).

It is an as-yet completely undescribed fossil flora, characterized by an absence of leaves with serrated edges; all Ione Flora botanic specimens encountered possess entire margins; that is to say, the leaf edges are uniformly smooth, lacking notches. Such a prevalence of smooth-margin fossil leaves is in botanical analyses traditionally indicative of unusually wet and warm paleoenvironments--decidedly subtropical, in the main. Even though abundant leaf material from Lygodium Gulch and several additional productive Ione Formation localities in the vicinity of Ione is presently stored in the archival paleobotany catacombs of the University California Museum of Paleontology in Berkeley--the cumulative culmination of multiple collecting expeditions by various folks over a period of 12 years (1991 to 2003)--to the best of my knowledge (as of 2018) no formal peer-reviewed scientific examination of the middle Eocene Ione Flora exists.

Directly above the Eocene Ione Formation, in nonconformable stratigraphic relations (denoting a lengthy hiatus in regional terrestrial deposition), lies the late Oligocene to early Miocene Valley Springs Formation--a mid Cenozoic Era interval characterized by rhyolitic pyroclastic flows and airfall ash layers that accumulated within an ancestral Sierra Nevada foothill district punctuated by ephemeral lakes and localized vegetation-lush watercourses. While productive paleobotanical evidence is only sporadically encountered in the Valley Springs Formation, one specific locality on private property near San Andreas (12 miles northwest of Angels Camp), the County Seat of Calaveras County, does indeed yield numerous undescribed (in the professional paleobotanical literature) early Miocene leaves of oaks, willows, and an extinct fig, all accurately dated by radiometric methods at 22.9 million years old. The specimens occur as excellently preserved impressions set within a whitish-weathering rhyolite tuff that gold seekers of the early 1900s expelled from a now abandoned drift mine excavation.

Supplemental Valley Springs Formation fossil leaves from a few additional sites in California's Gold Country, western foothills of the Sierra Nevada--mainly in the vicinity of State Route 49 between Ione and Angels Camp--provide tantalizing paleoenvironmental indications of an early Miocene scene approximately 23 million years ago. The Valley Springs Flora is not large, yet it sheds invaluable light on an important period in mid Tertiary geologic history. Plants secured from all Valley Springs Formation localities include: undescribed pine; Nutmeg yew; Chinese maple; Boxelder maple; Oregon grape; an extinct alder; Pasadena oak; Canyon live oak; Chinese evergreen oak; swampbay; California bay; an extinct fig similar to the extant Moreton Bay fig; Western sycamore; Monterey ceanothus; Catalina ironwood (now grows in the wild only on the Channel Islands off the coast of southern California); Serpentine willow; and Western soapberry.

The geologically younger late Miocene to late Pliocene Mehrten Formation developed as andesitic sedimentary detritus within flood plains of rivers that had their source in the nascent Sierra Nevada to the immediate east. Some portions of the Mehrten contain thick beds of auriferous gravels, similar in richness to the older (Eocene-age) and more famous accumulations farther northeast in the western foothills of the Sierra Nevada. Many Gold Rush-era drift mines and shafts penetrate these gold-bearing gravels throughout the Mother Lode belt, and more recent explorations have demonstrated conclusively that productive horizons can still be discovered.

Abundant fossil plants have also been collected from at least two places in the late Miocene portions of the Mehrten Formation. One specific site near Columbia State Park, 26 miles south of Angels Camp--the fossil-bearing bed lies on private property, so I am not at liberty to divulge its exact location--has yielded abundant fossil leaves, a botanic association that provides vital information about the paleoenvironment of the California Gold Country approximately 10 million years ago. Side bar: during my first visit to the locality, I contracted a devastating case of poison oak dermatitis, which ultimately prompted a late night trip to an emergency room to acquire a physician's prescribed two-week regimen of steroids--the proscribed medical treatment for such an extreme reaction to urushiol.

Some 28 species of Miocene plants have been identified from the Columbia site, including Chinese maple, laurel sumac, American holly, Mexican grapeholly, Oregon grape, Pagoda dogwood, Black tupelo, Pacific madrone, Chinese rhododedron, extinct Asiatic oak (first specimen discovered at the Pliocene-age Petrified Forest in Sonoma County, California), Engelmann oak, coastal sage scrub oak, Bitternut hickory, swampbay, California bay, Eastern redbud, New Mexico locust, Southern magnolia, Desert olive, Western sycamore, Alabama supplejack, Mountain mahogany, Chinese hawthorn, Brewer's willow, Lewis' mock-orange, western hackberry, American elm, and Knobcone pine.

The specimens suggest that a mixture of four distinct floral communities existed here 10 million yeas ago: A border-redwood element, with modern relatives now living in the central Sierra Nevada, south Coast Ranges, and southern California; an oak woodland-chaparral association, presently distributed throughout the Southwest; an eastern American element, whose modern-day representatives now live in the southeastern United States (elm and magnolia, in particular); and an East Asian element, with now living species native to China and the Philippines.

Based on the known needs of living members of the fossil flora, precipitation patterns were quite different some 10 million years ago in the ancestral Gold Country. Rainfall was roughly 25 to 30 inches per year, distributed throughout the winter and summer months. Today summers are characteristically dry; a continental, Mediterranean climate has eliminated from the modern flora all members of the East Asian and eastern American botanic communities.

It is estimated that the fossils near Columbia accumulated at an elevation no higher than 500 feet. Presently, the locality lies at an altitude of 2,000 feet. Topographic relief in the region was apparently rather low. The late Miocene Sierra foothill belt was essentially a broad flood plain with interspersed undulating hills in which rivers and streams wandered their way to the Pacific Ocean to the west.

According to climatic preferences of modern-day relatives of the fossil plants, both summer and winter months were considerably more moderate some 10 million years ago. Winter weather was probably quite comfortable since frosts were rare if not nonexistent in the lowlands. And while summer temperatures likely exceeded 90 degrees at times, there is no indication that they often topped 100. The moderating influence of sea breezes from the nearby Pacific, which had periodically flooded the Great Central Valley through the Tertiary Period, probably contributed to an almost perfect climate. Today, summertime temperatures in the Sierra foothills regularly surpass 100 degrees, and pollution from the Great Central Valley to the west surges against the base of the mountains with increasing frequency.

A second exceptional Mehrten Formation paleobotanical locality occurs several miles east of Nevada City/Grass Valley (about 85 miles north of Angels Camp). It's absolute geologic age is established through radiometric analyses at 9.5 million years old, or late Miocene on the geologic time scale. Although the leaf-rich andesitic shales of fluviatile origin had been exposed by hydraulic gold miners during the mid 1850s to 1870s (a gold nugget taken from the diggings in 1855 weighed in at 11.6 pounds--the 22nd-heaviest gold nugget ever discovered in California), nobody bothered to study the remarkable paleobotany preserved there until the early 1940s.

32 species of late Miocene plants have been identified from the Mehrten locality east of Nevada City/Grass Valley (they are contiguous communities in California's northern Mother Lode country), including: Port orford cedar (not really a cedar, of course, but rather a cypress); Coast redwood; Boxelder maple; an extinct species of Mahonia (barberry); oval-leaved viburnum; Pacific madrone; manzanita; Sierra laurel; Blue oak; Valley oak; California black oak; Oracle oak; an extinct oak similar to the extant Chinese evergreen oak; Oriental white oak; Interior live oak; American sweetgum; Ohio buckeye; Eastern black walnut; Red bay; California bay; roundleaf greenbrier; Western sycamore; Alabama supplejack; Buckbrush; mountain hawthorn; Hollyleaf cherry; Black cottonwood; Quaking aspen; Fremont cottonwood; Shining willow; Mexican buckeye; American elm; an extinct species of grapevine.

Today, the Mehrten Flora east of Nevada City/Grass Valley resides at an altitude slightly over 4,000 feet within a mixed-conifer Sierran forest association of Ponderosa pine, Incense cedar, White fir, and California Black oak. But some 9.5 million years ago, the fossil flora likely accumulated at elevations no higher than 2,000. The paleoenvironmental setting probably resembled areas in California that host the southernmost occurrences of Coast Redwood--notably Big Sur and the south side of Carmel Valley (northwest of Big Sur), approximately 7.5 miles inland from the Pacific Ocean. Precipitation was in the neighborhood of 35 to 40 inches per year, and that distributed liberally during both the summer and winter months--a weather pattern that contrasts radically with modern Mediterranean-style meteorology, where all effective rain falls during the winter months. Temperatures were much more moderate than those at the fossil site today, with cooler summers and little to no frost during the colder months (even at 4,000 feet, Sierran summer readings surpass 90 degrees).

In addition to the rich paleobotanical record, the Mehrten Formation also yields locally plentiful vertebrate fossil material approximately 7 to to 4 million years old, including: ground sloths (Megalonyx mathisi, Pliometanastes protistus); dogs (Borophagus parvus, Osteoborus, Vulpes sp.); cats (Felis sp., Machairodus coloradensis, Pseudaelurus sp.); a badger (Pliotaxidea garberi); racoon (Procyon sp.); beavers (Castor sp. and Dipoides williamsi); a vole (Copemys sp.); pocket gopher Cupidinimus sp.); Kangaroo rat (Dipodomys sp.); North american rock squirrel (Otospermophilus argonotus); hares (Hypolagus sp.); horses (Dinohippus coalingensis, Hipparion mohavense, Nannippus tehonensis, Neohipparion molle, Pliohippus coalingensis, P. interpolatus); rhinos (Aphelops sp., Teleoceras sp.); gompotheres (Gomphotherium sp., Platybelodon sp.); mastodons (Mammut americanum); camels (Altomeryx sp., Paracamelus sp., Pliauchenia edensis, Procamelus sp.); peccary (Prosthennops sp.); pronghorns (Garberoceras sp., Merycodus sp., Sphenophalos sp., Tetrameryx sp.); deer (Pediomeryx sp.); Pacific newt (Taricha); Pacific giant salamander (Dicamptodon); Slender salamanders (Butrachoseps); Climbing salamanders (Aneides); an extinct giant tortoise (Hesperotestudo); Spotted turtle (Clemmys); Gopher tortoises (Gopherus); Star tortoises (Geochelone); an extinct sabertooth salmon (Smilodonichthys); and Sacramento blackfish (Orthodon).

Most of the Mehrten mineralized skeletal material derives from several classic and long-established fossil localities, but one newer discovery described in a 2018 scientific document yielded something rather extra-extraordinary, as it were--canid coprolites--AKA, petrified poop from Borophagus parvus, an extinct bone cracking dog, probably analogous in behavior to the modern striped and brown hyenas. The Mehrten Formation fossil feces, collected some 55 miles south of Angels Camp in a transition zone situated between the Great Central Valley and the western foothills of the Sierra Nevada, provided the first unambiguous evidence that Borophagus canids (obligate large-prey hunters) consumed large amounts of bone, an idea that vertebrate paleontologists had long suspected but could never directly prove until now.

In addition to the "Big Three" Tertiary Period leaf-bearing geologic rock units exposed in California's Gold Rush district (Ione Formation, Valley Springs Formation, and Mehrten Formation), a second major fossil plant-bearing area can be explored in the vicinity of Carson Pass, Sierra Nevada proper, at elevations from 8,000 to 9,200 feet; the turnoff is at Jackson, the County Seat of Amador County, about 11 miles east of Ione (28 miles north of Angels Camp). Not far from the famed summit, for example, named after intrepid Mountain Man and Army scout Kit Carson, locally abundant petrified woods--including at least one stump--occur within an unnamed middle Miocene formation, dated by radiometric methods (radioactive isotope analyses) at 14.7 million years old--a rock unti technically categorized as a volcanic debris flow/braided stream deposit, with common inclusion clasts that might represent repeated avalanches.

Fossil leaves can also be found near Carson Pass--from a specific site the late paleobotanist Daniel I. Axelrod (July 16, 1910 – June 2, 1998) had under formal scientific investigations for at least four decades; as a matter of fact--family, friends, and colleagues of Dr. Axelrod scattered his ashes in the vicinity of Frog Lake, not far from Carson Pass, on what would been his 88th birthday, July 16, 1998. The fossils occur at an elevation of approximately 9,200 feet in the andesitic sandstones and shales of an unnamed middle Miocene geologic rock unit calculated at around 16 million years old (preliminary geologic evaluations had placed the fossil flora in the Relief Peak Formation); the paleobanically significant sedimentary matrix represents stream and hyperconcentrated flood deposits, yielding a chiefly riparian association of plants whose modern day counterparts, in general, live at elevations no higher than 2,500 feet. Taxa dominants include the leaves of maple (Acer), tupelo (Nyssa), sycamore (Platanus), avocado (Persea), poplar (Populus), lingnut (Pterocarya), Catalina Ironwood (Lyonothamnus--a tree that presently grows in the wild only on the Channel Islands off the coast of southern California), oak (Quercus), elm (Ulmus), and willow (Salix); interestingly, no conifers occur in the so-called Carson Pass Flora. Today, the fossil site lies in the arctic-alpine zone of fell-fields and meadowland, above a subalpine forest of whitebark pine and mountain hemlock.

After reflecting on the rich regional Cenozoic Era paleontology of California's Carson Pass/Gold Rush areas--and visiting Angels Camp--it's time for the ride to the High Sierra fossil plants.

To reach the Mount Reba fossil-bearing area, first take State Route 4 northeast out of Angels Camp toward Ebbetts Pass. At a point 23 miles from Angles Camp, you will arrive at the turnoff to Calaveras Big Trees State Park. I most definitely recommend a side visit. Here you will find two of the finest groves of giant sequoia in existence. The North Grove receives most of the visitor attention, but if you really wish to experience the overwhelming wonder of an essentially pristine giant sequoia floral community, then head over to the less-frequented South Grove a few miles from the entrance gate.

A two-mile hike is required to reach the South Grove, but the going is easy (no serious elevations to ascend) and, once amidst the big trees, you will likely marvel at the undisturbed nature of the spectacle. The associated understory of plants which contribute to an ancient giant sequoia forest have not been trampled into submission as, unfortunately, they have been in Sequoia National Park, where millions of visitors each year wander among the trees, preventing the natural vegetation from reestablishing itself. This South Grove shows off the same unique grouping of big trees, pines, shrubs, and deciduous trees--all unchanged--that once covered all of west-central Nevada and most of east-to-central California some 16 to 5 million years ago.

Once you've explored Calaveras Big Trees State Park, it's time to proceed onward to the turnoff to the Mount Reba fossil plant locality in the general vicinity of an ultra-popular ski resort. From late fall to early spring thousands of enthusiasts pack up their equipment and head this way--the quality of the snow pack is according to experts quite extraordinary, conducive to a sensational skiing experience.

But prior to the ascent to the fossiliferous locality--assuming that the United States Forest Service (USFS) continues to allow vehicular access, mind you--take a moment to dispassionately evaluate your own ability to negotiate off-road a four-wheel drive vehicle over a steep, rocky, unimproved path in the mountains. I am not trying to scare anybody off here--far from it. In a seance, I am appealing to a sense of adventure. At the same time, I am providing a gentle warning to novice off-road drivers that, while the route is far from expert-only, it does require a modicum of technical proficiency in two or three places. Most of the trail is easily and safely negotiated.

If authorities no longer permit motorized access, you'll just have to hike the remaining distance to the Disaster Peak Formation paleobotanical area--the very same way I did upon my first visit; even though officials allowed vehicular travel at that date, I nevertheless voluntarily chose to walk to the site, not confidently anticipating that first time around that I'd be able to safely negotiate the unknown incline in my four-wheel drive mechanism.

Once at the convenient parking area near the fossil-bearing site at an elevation of almost 9,000 feet--and contingent of course on permission from the USFS to continue to collect fossil plants here, walk downslope from the parking spot along the narrow dirt trail. The first outcrops you encounter, in the roadcut along the left side of the path, contain the 7 million-year-old leaves. The fossil plants occur in the yellow-to-buff, moderately compacted andesitic sandstones of the upper Miocene Disaster Peak Formation. Widely scattered pieces of unidentified petrified wood also occur along the steep slopes to the right of the trail. But watch your footing here, as trying to hike over the weathered sandy mudstones and volcanic rocks is hazardous.

The Disaster Peak Formation exposed along the trail is approximately 29 feet thick. It's primarily a mudstone-sandstone andesite breccia--the hardened material remaining from a mudflow that moved with inexorable inevitability down a moist hillslope some 7 million years ago, a massive mudflow event probably triggered by a volcanic eruption in the neighborhood. Two rather thin sandstone beds in the section--2 feet, and 1.5 feet thick, respectively--yield all of the moderately common fossil leaves; the remainder of the deposit is unfossiliferous. A distinctive feature of the fossils in the sandstone is that they are curled and twisted, a telltale style of preservation that indicates that the mudflow contorted the leafy structures as it slid downslope.

Altogether, 14 species of fossil plants have been secured from the Disaster Peak Formation. The four most abundant forms in the sandstones are leafy branchlets from a cypress, Cupressus mokelumnensis (an extinct cypress that is similar to the living Chinese weeping cypress--now native to China); leafy twigs from a Douglas-fir, Pseudotsuga sonomensis; entire leaves from an evergreen live oak, Quercus pollardiana (Canyon live oak); and leaves from a species of tanbark oak, Lithocarpus klamathensis. In decreasing order of relative prevalence, the flora also contains a cattail, Typha lesquereuxii; a willow, Salix wildcatensis (arroyo willow); a white fir, Abies concoloroidea; a giant sequoia, Sequoiadendron cheneyii; a second species of willow, Salix hesperia (Pacific willow); an elm, Ulmus affinis (an extinct species most similar to the extant American elm); a species of sugar pine, Pinus prelambertiana; a pine, Pinus sturgisii (western yellow pine); a juniper, Juniperus sp.; and a third species of willow, Salix boisiensis (Scouler's willow).

In general, the fossil floral association resembles a modern-day Douglas-fir forest in the western foothills of the central to northern Sierra Nevada, at elevations of 2,000 to 3,000 feet; today, the fossiliferous section rests at an altitude of 8,650 feet, above the local timberline in the upper subalpine belt. During the upper Miocene, rainfall was likely as high as 40 inches per year, with storms distributed in both winter and summer months. This is in dramatic contrast with present-day weather patterns, which release virtually all of the effective precipitation as snow during the winter. But 7 million years ago summertime rain was a necessary occurrence, in order to account for the presence of cypress and elm in the local fossil record.

The species of cypress, Douglas-fir, evergreen live oak, and tanbark oak--which comprise 97.8 percent of the fossil specimens recovered from the flora--clearly lived nearest the actual site of deposition, probably along the cool shady north-facing slopes of a southwesterly draining valley. Farther upstream, white fir, sugar pine, yellow pine, and giant sequoia contributed to a mixed conifer forest. The drier slopes in this area supported specimens of juniper. The three species of willow thrived along the watercourses, no doubt forming dense thickets. The lone species of elm in the fossil record could have lived in the mixed conifer forest, where greater rates of precipitation would favor its survival. An interesting observation is that the most abundant member of the Disaster Peak Formation flora, the specific species of cypress, no longer lives anywhere in the United States; its closest modern-day relative is now native to China.

After analyzing the fossil leaf, twig, and branchlet material secured from the upper Miocene Disaster Peak Formation, paleobotanists have arrived at a fascinating line of thought. Perhaps it is possible to determine the time of year when the mudflow engulfed the plants. Numerous specimens of cypress, Douglas-fir, and oak, for example, appear to represent immature leafy structures---signifying that before they became buried by the mudflow the plants had just begun their first spurts of growth during the new season. It is a tentative conclusion, but the overall size and shape of the preserved plant structures suggests that the event which preserved them occurred during either spring or early summer.

Here is a fossil plant locality worth visiting: But only during the "dead of summer" through early fall, of course, when the roads at higher Sierra elevations remain "reliably" passable. Not only are excellent leaf and twig specimens from 14 species of upper Miocene plants available, but the scenery up there is absolutely stunning--a wide vista that takes in mile after mile of the pristine High Sierra Nevada back country, a true wilderness, one of the great natural treasures in America. As you stand there at an elevation of 8,650 feet, above local timberline, the Disaster Peak Formation fossils prove that 7 million years ago Douglas-fir, cypress, and giant sequoia thrived where today no trees exist.

On-Site Images

The Mount Reba locality in the upper Miocene Disaster Peak Formation

Click on the images for larger pictures

Click on the image for a larger pictue. A paleobotany aficionado inspects an outcrop of the fossil plant-bearing upper Miocene Disaster Peak Formation. The primary fossil leaf locality in the Disaster Peak Formation occurs just downslope from this spot. The vista is almost due north. Sierra Nevada batholithic grantites in panoramic perspective to the skyline. That brownish peak at upper left is composed of Miocene-age andesitic volcanic rocks.

Click on the image for a larger pictue. Enthusiastic paleobotany participants investigate the primary fossil plant locality in the upper Miocene Disaster Peak Formation. Viewing perspective is roughly northward. Today, the site lies at an altitude of 8,640 feet, but the 14 species of plants preserved here prove that 7 million years ago the very spot, now slightly above the local timberline, would have resembled a modern Douglas-fir forest in the lower western foothills of the Sierra Nevada at elevations no higher than 2,500 feet, with subordinate groves of giant sequoia thriving nearby.

The four most abundant fossil plant forms secured from the Disaster Peak Formation sandstones are leafy branchlets from a cypress, Cupressus mokelumnensis (an extinct cypress that is similar to the living Chinese weeping cypress--now native to China; leafy twigs from a Douglas-fir, Pseudotsuga sonomensis; entire leaves from an evergreen live oak, Quercus pollardiana (Canyon live oak); and leaves from a species of tanbark oak, Lithocarpus klamathensis. In decreasing order of relative prevalence, the flora also contains a cattail, Typha lesquereuxii; a willow, Salix wildcatensis (arroyo willow); a white fir, Abies concoloroidea; a giant sequoia, Sequoiadendron cheneyii; a second species of willow, Salix hesperia (Pacific willow); an elm, Ulmus affinis (an extinct species most similar to the extant American elm); a species of sugar pine, Pinus prelambertiana; a pine, Pinus sturgisii (western yellow pine); a juniper, Juniperus sp.; and a third species of willow, Salix boisiensis (Scouler's willow).

Click on the image for a larger picture. A seeker of paleobotanical adventure inspects andesitic tuffs of the upper Miocene Disaster Peak Formation for fossil plant material. Relatively common pieces of as-yet unidentified petrified wood weather out of this specific volcanic sequence in the Disaster Peak Formation.

Click on the image for a larger picture. A vista looking back southwestward along the way to the upper Miocene Disaster Peak Formation fossil plants--a quintessentially unmaintained dirt trail in the Sierra Nevada wilderness. The view is to the western foothills of the Sierra Nevada. Miocene volcanics comprise the foreground (roughly to center of photograph) and the hills that mostly lie below the skyline in extreme distance

Click on the image for a larger picture. Directional orientation here is roughly due north from the upper Miocene Disaster Peak Formation fossil locality. Sierra Nevada granitic basement complex spreads to the horizon. Peak at upper left is developed in late Miocene andesite volcanics.

Images From Calaveras Big Trees State Park, California

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Click on the image for a larger picture. Seekers of outdoor adventure stand at the base of a Big Tree, a giant sequoia (Sierra redwood), at the South Grove, Calaveras Big Trees State Park, Calaveras County, California, western slopes of the Sierra Nevada. Another Big Tree rises at far right; that's the trunk of a sugar pine--an impressive conifer in its own right--at foreground left, by the way. The South Grove at Calaveras Big Trees makes an excellent side trip when visiting the High Sierra Nevada fossil plants in the upper Miocene Disaster Peak Formation.

Click on the image for a larger picture. Botany enthusiasts explore the South Grove of giant sequoias (Sierra redwood) at Calaveras Big Trees State Park, Calaveras County, California, western slopes of the Sierra Nevada. The South Grove at Calaveras Big Trees makes an excellent side trip when visiting the High Sierra Nevada fossil plants in the upper Miocene Disaster Peak Formation. By the way, many of those other conifers growing alongside the two giant sequoias in the photographs are amazingly impressive specimens in their own right.

Click on the image for a larger picture. Botany enthusiasts explore the South Grove of giant sequoias (Sierra redwood) at Calaveras Big Trees State Park, Calaveras County, California, western slopes of the Sierra Nevada. The South Grove at Calaveras Big Trees makes an excellent side trip when visiting the High Sierra Nevada fossil plants in the upper Miocene Disaster Peak Formation. By the way, many of those other conifers growing alongside the two giant sequoias in the photographs are amazingly impressive specimens in their own right.

The Mark Twain Cabin On Jackass Hill

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Click on the image for a larger picture. The Mark Twain cabin, California Historical Landmark 138. A replica (constructed in 1922--though the fireplace and chimney are original) of the cabin on Jackass Hill, about 6 miles south of Angels Camp in California's Gold Rush Country, where Mark Twain (given name Samuel Langhorne Clemens) lived with the Gillis brothers (local miners) during the winter of 1864-'65. He arrived there on December 4, 1864, from San Francisco. It's the place where in early 1865 he wrote "The Celebrated Jumping Frog of Calaveras County" (eventually published in the New York Saturday Press on November 18, 1865)--the very short story that first brought him national fame as a writer. A Google Earth street car perspective that I edited and processed through photoshop.

Here's the note Twain made in his notebook in January, 1865, while staying at Jackass Hill--the germ of the story that eventually became "The Celebrated Jumping Frog of Calaveras County:" "Coleman with his jumping frog — bet stranger $50 — stranger had no frog & C got him one — in the meantime stranger filled C's frog full of shot & he couldn't jump — the stranger's frog won."

Images From The Lygodium Gulch Fossil Leaf Locality

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Click on the image for a larger picture. Students and their professors from a university and a community college help the late paleobotanist Howard Schorn (next bottom photo, below) standing in trench in pale blue long-sleeve shirt and wearing a hat)--former Collections Manager of fossil plants at the University California Museum of Paleontology--collect fossil leaves during a two day expedition to classic Lygodium Gulch, not far from Ione, California, on private property, in the middle Eocene Ione Formation, approximately 49 to 45 million years old. The Ione is one of three fossil plant-bearing Tertiary Period rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation paleobotanical locality in the High Sierra Nevada, Alpine County; the other two are the late Oligocene to lower Miocene Valley Springs Formation and the upper Miocene Mehrten Formation. Two supplemental areas in the California's High Sierra Carson Pass region--east of Jackson (county seat of Amador County)--also yield Tertiary-age petrified wood and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

In addition to abundant, as-yet unidentified leaves (as of 2018, no scientific analysis of the Ione Flora has ever been published in the peer-reviewed paleobotanical literature), Lygodium Gulch also yields important specimens of the species for which the locality was informally named--an extinct climbing fern, Lygodium kaulfussi, whose closest living analog is the American climbing fern, Lygodium palmatum, now endemic to the US southeast, from roughly Appalachia to the South. Image taken on October 27, 2002.

Click on the image for a larger picture. Students and their professors from a university and a community college help the late paleobotanist Howard Schorn (standing in trench in pale blue long-sleeve shirt and wearing a hat)--former Collections Manager of fossil plants at the University California Museum of Paleontology--collect fossil leaves during a two day expedition to classic Lygodium Gulch, not far from Ione, California, on private property, in the middle Eocene Ione Formation, approximately 49 to 45 million years old. The Ione is one of three fossil plant-bearing Tertiary Period rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation paleobotanical locality in the High Sierra Nevada, Alpine County; the other two are the late Oligocene to lower Miocene Valley Springs Formation and the upper Miocene Mehrten Formation. Two supplemental areas in the California's High Sierra Carson Pass region--east of Jackon (county seat of Amador County)--also yield Tertiary-age petrified wood and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

In addition to abundant, as-yet unidentified leaves (as of 2018, no scientific analysis of the Ione Flora has ever been published in the peer-reviewed paleobotanical literature), Lygodium Gulch also yields important specimens of the species for which the locality was informally named--an extinct climbing fern, Lygodium kaulfussi, whose closest living analog is the American climbing fern, Lygodium palmatum, now endemic to the US southeast, from roughly Appalachia to the South. Image taken on October 26, 2002.

Images From The Carson Pass Fossil Plant Localities

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Click on the image for a larger picture. A roadcut in the Carson Pass area that exposes an unnamed middle Miocene unit, dated by radiometric methods (radioactive isotope analyses) at 14.7 million years old; locally in the Carson Pass district this specific rock formation produces abundant petrified woods. It's primarily a combination volcanic debris flow/braided stream deposit, with common inclusion clasts that might represent repeated avalanches. A Google Earth street car perspective that I edited and processed through photoshop.

Click on the image for a larger picture. A view southward near Carson Pass to a Sierra Nevada spectacle--and, a famous fossil leaf locality--a site the late paleobotanist Daniel I. Axelrod (July 16, 1910--June 2, 1998) had under formal scientific investigations for at least four decades. That patch of shale and sandstone at lower right yields common fossil leaves from an unnamed middle Miocene geologic rock unit usually calculated at around 16 million years old (originally thought to represent the Miocene Relief Peak Formation); the paleobanically significant sedimentary detritus accumulated in streams and as hyperconcentrated flood deposits. Elevation here is around 9,200 feet, above the local timberline. Note patches of lingering snow; photograph taken during a late August visit. The middle Miocene leaf locality near Carson Pass yields a chiefly riparian association whose modern day counterparts in general live at elevations no higher than 2,500 feet. Taxa dominants include the leaves of maple (Acer), tupelo (Nyssa), sycamore (Platanus), avocado (Persea), poplar (Populus), lingnut (Pterocarya), Catalina Ironwood (Lyonothamnus--a tree that presently grows in the wild only on the Channel Islands off the coast of southern California), oak (Quercus), elm (Ulmus), and willow (Salix); interestingly, no conifers occur in the so-called Carson Pass Flora. Today, the fossil site lies in the arctic-alpine zone of fell-fields and meadowland, above a subalpine forest of whitebark pine and mountain hemlock.

Click on the image for a larger picture. Frog Lake (elevation 8,865 feet) in the vicinity of Carson Pass. Near here--on July 16, 1998--a group of family and friends spread the ashes of paleobotanist Daniel I. Axelrod on the anniverary of what would have been his 88th birthday.

Images From The Valley Springs Formation Fossil Leaf Locality

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Click on the images for larger pictures. Top and bottom: Two views of a prime fossil leaf locality, presently situated on private property, in the lower Miocene portion of the late Oligocene to lower Miocene Valley Spring Formation. The whitish areas in both photographs represent leaf-bearing blocks of rhyolite tuff (dated radiometrically at 23 million years old) that gold miners ejected from a now abandoned drift mine. Rather common undescribed (in the professional paleobotanical literature) leaf impressions of oaks, willows, and an extinct variety of fig can be found here on those dumps of Valley Springs Formation rhyolite tuff--with the property owner's explicit permission, of course.

Supplemental Valley Springs Formation fossil leaves from additional sites in California's Gold Country, western foothills of the Sierra Nevada--from rhyolitic exposures situated between Nevada City/Grass Valley to the north and Le Grange to the south--provide tantalizing paleoenvironmental indications of an early Miocene scene approximately 23 million years ago. The Valley Springs Flora is not large, yet it sheds invaluable light on an important period in mid Tertiary geologic history. Plants secured from all Valley Springs Formation localities include: undescribed pine; Nutmeg yew; Chinese maple; Boxelder maple; Oregon grape; an extinct alder; Pasadena oak; Canyon live oak; Chinese evergreen oak; swampbay; California bay; an extinct fig similar to the extant Moreton Bay fig; Western sycamore; Monterey ceanothus; Catalina ironwood (now grows in the wild only on the Channel Islands off the coast of southern California); Serpentine willow; and Western soapberry.

The Valley Springs Formation is one of three fossil plant-bearing Tertiary Period rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation paleobotanical locality in the High Sierra Nevada, Alpine County; the other two are the middle Eocene Ione Formation and the upper Miocene Mehrten Formation. Two supplemental areas in the California's High Sierra Carson Pass region--east of Jackon (county seat of Amador County)--also yield Tertiary-age petrified wood and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

Images From The Mehrten Formation Fossil Leaf Localities

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Click on the images for larger pictures. Top and bottom: Two archival photographs of classic fossil leaf localities in the late Miocene Mehrten Formation--one of three famous Tertiary Period fossil plant-bearing rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the Disaster Peak Formation plants in the High Sierra Nevada, Alpine County; the other two are the middle Eocene Ione Formation and the late Oligocene to lower Miocene Valley Springs Formation. Both photographs taken during the early 1940s; courtesy a specific scientific publication. Two supplemental areas in the California's High Sierra Carson Pass region--east of Jackon (county seat of Amador County)--also yield Tertiary-age petrified wood and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

Top--The late-middle Mehrten Formation fossil leaf-bearing site (about 10 million years old) near Columbia State Park, California, about 26 miles south of Angels Camp (convenient turnoff point for the Disaster Peak Formation paleobotanical site)--an old gold prospect currently on private property, marked by the prominent excavation. Some 28 species of Miocene plants have been identified from this locality, including Chinese maple, laurel sumac, American holly, Mexican grapeholly, Oregon grape, Pagoda dogwood, Black tupelo, Pacific madrone, Chinese rhododedron, extinct Asiatic oak (first specimen discovered at the Pliocene-age Petrified Forest in Sonoma County, California), Engelmann oak, coastal sage scrub oak, Bitternut hickory, swampbay, California bay, Eastern redbud, New Mexico locust, Southern magnolia, Desert olive, Western sycamore, Alabama supplejack, Mountain mahogany, Chinese hawthorn, Brewer's willow, Lewis' mock-orange, western hackberry, American elm, and Knobcone pine.

Bottom--This is the early-late Mehrten Formation leaf-yielding locality (9.5 million years old) several miles east of Nevada City/Grass Valley (they are contiguous communities), northern Mother Lode country, about 85 miles north of Angels Camp (the turnoff point for the Disaster Peak Formation fossil plant-bearing area). The paleobotanic bonanza occurs along the cliff face, originally exposed by hydraulic gold miners in the mid 1850s. A gold nugget from this area, by the way, weighed in at 11.6 pounds, making it the 22nd heaviest gold nugget ever discovered in California. 32 species of late Miocene plants have been identified from this Mehrten locality east of Nevada City/Grass Valley, including: Port orford cedar (not really a cedar, of course, but rather a cypress); Coast redwood; Boxelder maple; an extinct species of Mahonia (barberry); oval-leaved viburnum; Pacific madrone; manzanita; Sierra laurel; Blue oak; Valley oak; California black oak; Oracle oak; an extinct oak similar to the extant Chinese evergreen oak; Oriental white oak; Interior live oak; American sweetgum; Ohio buckeye; Eastern black walnut; Red bay; California bay; roundleaf greenbrier; Western sycamore; Alabama supplejack; Buckbrush; mountain hawthorn; Hollyleaf cherry; Black cottonwood; Quaking aspen; Fremont cottonwood; Shining willow; Mexican buckeye; American elm; an extinct species of grapevine.

 

Click on the image for a larger picture. Paleobotany enthusiasts (under the auspices of the University California Museum of Paleontology) collect fossil leaves at the Mehrten Formation leaf-yielding locality several miles east of Grass Valley/Nevada City--they are contiguous communities that lie about 85 miles north of Angels Camp (turnoff point for the High Sierra Nevada Disaster Peak Formation fossil plant-bearing area)--northern Mother Lode country. The paleobotanic bonanza occurs along a cliff face, originally exposed by hydraulic gold miners in the mid 1850s. A gold nugget from this area, by the way, weighed in at 11.6 pounds, making it the 22nd heaviest gold nugget ever discovered in California. Photograph taken on October 16, 1993.

32 species of early-late Miocene plants have been identified from this early-late Mehrten Formation locality (9.5 million years old) east of Nevada City/Grass Valley, including: Port orford cedar (not really a cedar, of course, but rather a cypress); Coast redwood; Boxelder maple; an extinct species of Mahonia (barberry); oval-leaved viburnum; Pacific madrone; manzanita; Sierra laurel; Blue oak; Valley oak; California black oak; Oracle oak; an extinct oak similar to the extant Chinese evergreen oak; Oriental white oak; Interior live oak; American sweetgum; Ohio buckeye; Eastern black walnut; Red bay; California bay; roundleaf greenbrier; Western sycamore; Alabama supplejack; Buckbrush; mountain hawthorn; Hollyleaf cherry; Black cottonwood; Quaking aspen; Fremont cottonwood; Shining willow; Mexican buckeye; American elm; an extinct species of grapevine.

Images Of Fossils

Upper Miocene Disaster Peak Formation

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Click on the image for a larger picture. Plant specimen preserved on a chunk of andesitic sandstone from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Approximately 7 million years old. It's a twig from a Douglas-fir, called scientifically Pseudotsuga menziesii.

Click on the image for a larger picture. Plant specimen preserved on a chunk of andesitic sandstone from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Approximately 7 million years old. It's an evergreen live oak leaf, called scientifically Quercus pollardiana; it most closely resembles the modern Canyon live oak, endemic to many of California's mountain ranges.

Click on the image for a larger picture. An evergreen live oak branchlet, with leaves still attached, from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Roughly 7 million years old. Called scientifically Quercus pollardiana--it is the Miocene equivalent of the modern Canyon live oak, endemic to many California mountain ranges. Preserved on a piece of andesitic sandstone.

Click on the image for a larger picture. Petrified wood from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Approximately 7 million years old. Note the US dime currency for scale. Common, but widely scattered pieces of petrified wood occur in the vicinity of the primary leaf-bearing section of the Disaster Peak Formation.

Click on the image for a larger picture. Fossil plant specimen from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Preserved on a chunk of andesitic sandstone. Approximately 7 million years old. It's a branchlet from an extinct variety of cypress, called scientifically Cupressus mokelumnensis; it is most similar to the living Chinese weeping cypress native to southwestern and central China. Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil plant specimen from the upper Miocene Disaster Peak Formation, High Sierra Nevada, Alpine County, California. Preserved on a chunk of andesitic sandstone. Approximately 7 million years old. It's a leaf from the willow Salix boisiensis, whose closest living counterpart is Scouler's willow, native to the western United States and ranging through Canada to Alaska. Image courtesy a specific scientific document.

Middle Eocene Ione Formation

Late Oligocene to Early Miocene Valley Springs Formation

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Click on the image for a larger picture. A fossil leaf from a Tertiary Period geologic rock formation one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation plants, High Sierra Nevada. It's an undescribed leaf (as of 2018, not yet identified in the published paleobotanical literature) from the middle Eocene Ione Formation (approximately 48 to 45 million years old) exposed at classic Lygodium Gulch, not far from Ione, Amador County, California.

Click on the image for a larger picture. A fossil leaf from a Tertiary Period geologic rock formation one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation plants, High Sierra Nevada. It's a fig leaf from the lower Miocene Valley Springs Formation, from a locality near San Andreas, County Seat of Calaveras County, Gold Country, California. Called scientifically Ficus macrophyllum--the presumably extinct Miocene counterpart of the living Ficus macrophylla--the Moreton Bay fig native to eastern Australia. Preserved on a chunk of rhyolite tuff.

Fossil Plants From The Carson Pass Area

Unnamed Middle Miocene Rock Formations

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Click on the image for a larger picture. A fossil plant from the Carson Pass area, Sierra Nevada, California. It's a petrified stump preserved in an unnamed geologic rock unit dated by radiometric methods (radioactive isotope analyses) at 14.7 million years old; the material from which the stump protrudes is a trachyandesite ash flow tuff, with subordinate debris flow deposits. Photograph courtesy geologists Cathy J. Busby and Keith Putirka.

Click on the image for a larger picture. A fossil plant from the Carson Pass area, Sierra Nevada, California. It's a a fossil avocado leaf (genus Persea) from an unnamed geologic rock deposit that paleobotanists usually estimate at around 16 million years old. The specimen came from a locality that presently lies at roughly 9,200 feet, above the local timberline, above a subalpine forest composed of whitebark pine and mountain hemlock.

Upper Miocene Mehrten Formation Fossil Leaves

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Click on the image for a larger picture. A fossil leaf from an Oregon grape, referred to scientifically as Mahonia aguifolium. Specimen is approximately 10 million years old; it's from the early late Miocene Mehrten Formation paleobotanical locality near Columbia State Park. The Mehrten is one of three Tertiary Period geologic rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation plants, High Sierra Nevada; the other two are the middle Eocene Ione Formation and the late Oligocene to early Miocene Valley Springs Formation. Two supplemental localities in California's High Sierra Carson Pass area (east of Jackson, county seat of Amador County) also yield petrified woods and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

Click on the image for a larger picture. A fossil leaf from an oak, named scientifically Quercus remingtoni--it's considered the Miocene analog to the living Quercus morehus, which in actual fact is a naturally occurring hybrid between a deciduous oak (Quercus kelloggii--the California black oak) and an evegreen live oak (Quercus wislizeni--the interior live oak). From the early late Miocene Mehrten Formation fossil leaf locality several miles east of Nevada City/Grass Valley, Northern Mother Lode country, California. It's 9.5 million years old. The Mehrten is one of three Tertiary Period geologic rock formations one can examine in California's Gold Country, western foothills of the Sierra Nevada, along the route to the upper Miocene Disaster Peak Formation plants, High Sierra Nevada; the other two are the middle Eocene Ione Formation and the late Oligocene to early Miocene Valley Springs Formation. Two supplemental localities in California's High Sierra Carson Pass area (east of Jackson, county seat of Amador County) also yield petrified woods and fossil leaves from two unnamed (in the published scientific literature) geologic rock formations of middle Miocene age.

Miocene Mehrten Formation (about 10 million years old)

Fossil leaves from the locality near Columbia State Park, California

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Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. Left--Specimen at left in photograph is from what paleobotanists call Nyssa elaenoides, the Miocene variety of today's Black tupelo; leaf at right in the image is called Rhus mensae, the Miocene counterpart of the modern laurel sumac. Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. Two oak leaves referred to Quercus convexa, which is the Miocene equivalent of the modern Pasadena oak (also called the Engelmann oak). Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. Left to right: Crataegus newberryi, which most closely resembles the living mountain hawthorn; middle--Philadelphus nevadensis, the Miocene analog of the modern Lewis' mock-orange; Cercocarpus antiquus, which is equivalent to the living mountain mahogany. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. It's called scientifically Persea coalingensis, the fossil variety of the extant swampbay. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. It's called scientifically Carya typhinoides, a Miocene counterpart of the modern Bitternut hickory. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality near Columbia State Park, Gold Country, western foothills of the Sierra Nevada, California. It's called scientifically Quercus convexa, the Miocene equivalent of the living Pasadena oak (also called the Engelmann oak). Photograph courtesy a specific technical document.

Upper Miocene Mehrten Formation (9.5 million years old)

Fossil leaves from the locality east of Grass Valley/Nevada City, California

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Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Quercus pseudo-lyrata, the fossil counterpart of the modern California black oak. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Platanus paucidentata, the Miocene analog to the living western sycamore. Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Two leaves from Quercus remingtoni, a species that paleobotanists consider the Miocene analog to the living Quercus morehus, which is actually a naturally occurring hybrid between a deciduous oak (Quercus kelloggii--the California black oak) and an evegreen live oak (Quercus wislizeni--the interior live oak). Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Leaves from Quercus winstanleyi and Quercus simulata (left to right)--the fossil equivalents of the Oriental white oak and the Chinese evergreen oak, respectively. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Populus prefremontii, the Miocene variety of today's Fremont's cottonwood (also called the Alamo cottonwood). Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Salix hesperia, the fossil equivalent of the living Pacific willow. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Quercus prelobata, the fossil variety of today's Valley oak. Photograph courtesy a specific technical document.

Click on the image for a larger picture. A fossil leaf from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. Called Ugnadia clarki, the Miocene counterpart of the extant Mexican buckeye. Photograph courtesy a specific technical document.

Click on the image for a larger picture. Fossil leaves from the upper Miocene Mehrten Formation locality several miles east of Grass Valley/Nevada City (they are contiguous communities), Northern Mother Lode country, California. All three leaves belong to Quercus remingtoni, a species that paleobotanists consider the Miocene analog to the living Quercus morehus, which in actual fact is a naturally occurring hybrid between a deciduous oak (Quercus kelloggii--the California black oak) and an evegreen live oak (Quercus wislizeni--the interior live oak). Photograph courtesy a specific technical document.

Upper Miocene Mehrten Formation Vertebrate Fossils

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Click on the image for a larger picture. Premaxillary teeth from the extinct giant spike-toothed salmon (also called the sabertooth salmon) Oncorhynchus rastrosus, which lived roughly 12 to 5 million years ago during the mid Miocene to early Pliocene. The roughly 5 million year-old specimens came from a locality in the early Pliocene section of the upper Miocene to late Pliocene Mehrten Formation approximately 55 miles south of Angels Camp (turnoff point for the fossil plant bonanza in the High Sierra Nevada, Alpine County, California) in a transition zone between the Great Central Valley and the western Sierra Nevada foothills. Size-reference vertical bars in image are one inch long, by the way. Letters A, B, and F are left teeth--the remainder are right teeth. Estimated size for the giant spike-toothed salmon is six foot three inches long; probably it weighed in excess of 375 pounds. Photograph courtesy a specific scientific document.

Click on the image for a larger picture. Canid jaw material from the upper Miocene portion of the late middle through late Pliocene Mehrten Formation. These specimens are roughly 6 million years old. I modified the image from a freely available photograph, which unfortunately provided no identifying information. Bar scale is presumably one centimeter. Is is well established by vertebrate paleontologists, though, that as presently understood (2018) the Mehrten Formation yields four species of canids: two borophagines--the famous bone-crackers Borophagus parvus and B. secundus of probable hyena-like dietary behavior--and two canines (related to modern dogs--Eucyon davisi and Vulpes stenognathus). Photograph courtesy a specific scientific document.

Upper Miocene Mehrten Formation Coprolite

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Click on the image for a larger picture. Three viewing perspective of the same canid coprolite (petrified poop) from the upper Miocene Mehrten Formation. The specimen is roughly 6 million years old and probably came from a borophagine canid called Borphagus parvus, an extinct bone cracking dog of presumed hyena-like dietary preferences. Photograph courtesy a specific technical document.

My Other Web Sites--musical and paleontological

Web sites I have created pertaining to music

Paleontology-Related Pages

Web sites I have created pertaining to fossils

  • Fossils In Death Valley National Park: A site dedicated to the paleontology, geology, and natural wonders of Death Valley National Park; lots of on-site photographs of scenic localities within the park; images of fossils specimens; links to many virtual field trips of fossil-bearing interest.
  • Fossil Insects And Vertebrates On The Mojave Desert, California: Journey to two world-famous fossil sites in the middle Miocene Barstow Formation: one locality yields upwards of 50 species of fully three-dimensional, silicified freshwater insects, arachnids, and crustaceans that can be dissolved free and intact from calcareous concretions; a second Barstow Formation district provides vertebrate paleontologists with one of the greatest concentrations of Miocene mammal fossils yet recovered from North America--it's the type locality for the Bartovian State of the Miocene Epoch, 15.9 to 12.5 million years ago, with which all geologically time-equivalent rocks in North American are compared.
  • A Visit To Fossil Valley, Great Basin Desert, Nevada: Take a virtual field trip to a Nevada locality that yields the most complete, diverse, fossil assemblage of terrestrial Miocene plants and animals known from North America--and perhaps the world, as well. Yields insects, leaves, seeds, conifer needles and twigs, flowering structures, pollens, petrified wood, diatoms, algal bodies, mammals, amphibians, reptiles, bird feathers, fish, gastropods, pelecypods (bivalves), and ostracods.
  • Fossils At Red Rock Canyon State Park, California: Visit wildly colorful Red Rock Canyon State Park on California's northern Mojave Desert, approximately 130 miles north of Los Angeles--scene of innumerable Hollywood film productions and commercials over the years--where the Middle to Late Miocene (13 to 7 million years old) Dove Spring Formation, along with a classic deposit of petrified woods, yields one of the great terrestrial, land-deposited Miocene vertebrate fossil faunas in all the western United States.
  • Late Pennsylvanian Fossils In Kansas: Travel to the midwestern plains to discover the classic late Pennsylvanian fossil wealth of Kansas--abundant, supremely well-preserved associations of such invertebrate animals as brachiopods, bryozoans, corals, echinoderms, fusulinids, mollusks (gastropods, pelecypods, cephalopods, scaphopods), and sponges; one of the great places on the planet to find fossils some 307 to 299 million years old.
  • Fossil Plants Of The Ione Basin, California: Head to Amador County in the western foothills of California's Sierra Nevada to explore the fossil leaf-bearing Middle Eocene Ione Formation of the Ione Basin. This is a completely undescribed fossil flora from a geologically fascinating district that produces not only paleobotanically invaluable suites of fossil leaves, but also world-renowned commercial deposits of silica sand, high-grade kaolinite clay and the extraordinarily rare Montan Wax-rich lignites (a type of low grade coal).
  • Ice Age Fossils At Santa Barbara, California--Journey to the famed So Cal coastal community of Santa Barbara (about a 100 miles north of Los Angeles) to explore one of the best marine Pleistocene invertebrate fossil-bearing areas on the west coast of the United States; that's where the middle Pleistocene Santa Barbara Formation yields nearly 400 species of pelecypod bivalve mollusks, gastropods, chitons, scaphopods, pteropods, brachiopods, bryozoans, corals, ostracods (minute bivalve crustaceans), worm tubes, and foraminifers.
  • Trilobites In The Marble Mountains, Mojave Desert, California: Take a trip to the place that first inspired my life-long fascination and interest in fossils--the classic trilobite quarry in the Lower Cambrian Latham Shale, in the Marble Mountains of California's Mojave Desert. It's a special place, now included in the rather recently established Trilobite Wilderness, where some 21 species of ancient plants and animals have been found--including trilobites, an echinoderm, a coelenterate, mollusks, blue-green algae and brachiopods.
  • Dinosaur-Age Fossil Leaves At Del Puerto Creek, California: Journey to the western edge of California's Great Central Valley to explore a classic fossil leaf locality in an upper Cretaceous section of the upper Cretaceous to Paleocene Moreno Formation; the plants you find there lived during the day of the dinosaur.
  • Early Cambrian Fossils Of Westgard Pass, California: Visit the Westgard Pass area, a world-renowned geologic wonderland several miles east of Big Pine, California, in the neighboring White-Inyo Mountains, to examine one of the best places in the world to find archaeocyathids--an enigmatic invertebrate animal that went extinct some 510 million years ago, never surviving past the early Cambrian; also present there in rocks over a half billion years old are locally common trilobites, plus annelid and arthropod trails, and early echinoderms.
  • A Visit To Ammonite Canyon, Nevada: Explore one of the best-exposed, most complete fossiliferous marine late Triassic through early Jurassic geologic sections in the world--a place where the important end-time Triassic mass extinction has been preserved in the paleontological record. Lots of key species of ammonites, brachiopods, corals, gastropods and pelecypods.
  • Fossil Plants At The Chalk Bluff Hydraulic Gold Mine, California: Take a field trip to the Chalk Bluff hydraulic gold mine, western foothills of California's Sierra Nevada, for leaves, seeds, flowering structures, and petrified wood from some 70 species of middle Eocene plants.
  • Fossils In Millard County, Utah: Take virtual field trips to two world-famous fossil localities in Millard County, Utah--Wheeler Amphitheater in the trilobite-bearing middle Cambrian Wheeler Shale; and Fossil Mountain in the brachiopod-ostracod-gastropod-echinoderm-trilobite rich lower Ordovician Pogonip Group.
  • Paleozoic Era Fossils At Mazourka Canyon, Inyo County, California: Visit a productive Paleozoic Era fossil-bearing area near Independence, California--along the east side of California's Owens Valley, with the great Sierra Nevada as a dramatic backdrop--a paleontologically fascinating place that yields a great assortment of invertebrate animals.
  • Late Triassic Ichthyosaur And Invertebrate Fossils In Nevada: Journey to two classic, world-famous fossil localities in the Upper Triassic Luning Formation of Nevada--Berlin-Ichthyosaur State Park and Coral Reef Canyon. At Berlin-Ichthyosaur, observe in-situ the remains of several gigantic ichthyosaur skeletons preserved in a fossil quarry; then head out into the hills, outside the state park, to find plentiful pelecypods, gastropods, brachiopods and ammonoids. At Coral Reef Canyon, find an amazing abundance of corals, sponges, brachiopods, echinoids (sea urchins), pelecypods, gastropods, belemnites and ammonoids.
  • Fossils From The Kettleman Hills, California: Visit one of California's premiere Pliocene-age (approximately 4.5 to 2.0 million years old) fossil localities--the Kettleman Hills, which lie along the western edge of California's Great Central Valley northwest of Bakersfield. This is where innumerable sand dollars, pectens, oysters, gastropods, "bulbous fish growths" and pelecypods occur in the Etchegoin, San Joaquin and Tulare Formations.
  • Field Trip To The Kettleman Hills Fossil District, California: Take a virtual field trip to a classic site on the western side of California's Great Central Valley, roughly 80 miles northwest of Bakersfield, where several Pliocene-age (roughly 4.5 to 2 million years old) geologic rock formations yield a wealth of diverse, abundant fossil material--sand dollars, scallop shells, oysters, gastropods and "bulbous fish growths" (fossil bony tumors--found nowhere else, save the Kettleman Hills), among many other paleontological remains.
  • A Visit To The Sharktooth Hill Bone Bed, Southern California: Travel to the dusty hills near Bakersfield, California, along the eastern side of the Great Central Valley in the western foothills of the Sierra Nevada, to explore the world-famous Sharktooth Hill Bone Bed, a Middle Miocene marine deposit some 16 to 15 million years old that yields over a hundred species of sharks, rays, bony fishes, and sea mammals from a geologic rock formation called the Round Mountain Silt Member of the Temblor Formation; this is the most prolific marine, vertebrate fossil-bearing Middle Miocene deposit in the world.
  • In Search Of Fossils In The Tin Mountain Limestone, California: Journey to the Death Valley area of Inyo County, California, to explore the highly fossiliferous Lower Mississippian Tin Mountain Limestone; visit three localities that provide easy access to a roughly 358 million year-old calcium carbate accumulation that contains well preserved corals, brachiopods, bryozoans, crinoids, and ostracods--among other major groups of invertebrate animals.
  • Middle Triassic Ammonoids From Nevada: Travel to a world-famous fossil locality in the Great Basin Desert of Nevada, a specific place that yields some 41 species of ammonoids, in addition to five species of pelecypods and four varieties of belemnites from the Middle Triassic Prida Formation, which is roughly 235 million years old; many paleontologists consider this specific site the single best Middle Triassic, late Anisian Stage ammonoid locality in the world. All told, the Prida Formation yields 68 species of ammonoids spanning the entire Middle Triassic age, or roughly 241 to 227 million years ago.
  • Late Miocene Fossil Leaves At Verdi, Washoe County, Nevada: Explore a fascinating fossil leaf locality not far from Reno, Nevada; find 18 species of plants that prove that 5.8 million years ago this part of the western Great Basin Desert would have resembled, floristically, California's lush green Gold Country, from Placerville south to Jackson.
  • Fossils Along The Loneliest Road In America: Investigate the extraordinary fossil wealth along some 230 miles of The Loneliest Road In America--US Highway 50 from the vicinity of Eureka, Nevada, to Delta in Millard County, Utah. Includes on-site images and photographs of representative fossils (with detailed explanatory text captions) from every geologic rock deposit I have personally explored in the neighborhood of that stretch of Great Basin asphalt. The paleontologic material ranges in geologic age from the middle Eocene (about 48 million years ago) to middle Cambrian (approximately 505 million years old).
  • Fossil Bones In The Coso Range, Inyo County, California: Visit the Coso Range Wilderness, west of Death Valley National Park at the southern end of California's Owens Valley, where vertebrate fossils some 4.8 to 3.0 million years old can be observed in the Pliocene-age Coso Formation: It's a paleontologically significant place that yields many species of mammals, including the remains of Equus simplicidens, the Hagerman Horse, named for its spectacular occurrences at Hagerman Fossil Beds National Monument in Idaho; Equus simplicidens is considered the earliest known member of the genus Equus, which includes the modern horse and all other equids.
  • Field Trip To A Vertebrate Fossil Locality In The Coso Range, California: Take a cyber-visit to the famous bone-bearing Pliocene Coso Formation, Coso Mountains, Inyo County, California; includes detailed text for the field trip, plus on-site images and photographs of vertebrate fossils.
  • Fossil Plants At Aldrich Hill, Western Nevada: Take a field trip to western Nevada, in the vicinity of Yerington, to famous Aldrich Hill, where one can collect some 35 species of ancient plants--leaves, seeds and twigs--from the Middle Miocene Aldirch Station Formation, roughly 12 to 13 million years old. Find the leaves of evergreen live oak, willow, and Catalina Ironwood (which today is restricted in its natural habitat solely to the Channel Islands off the coast of Southern California), among others, plus the seeds of many kinds of conifers, including spruce; expect to find the twigs of Giant Sequoias, too.
  • Fossils From Pleistocene Lake Manix, California: Explore the badlands of the Manix Lake Beds on California's Mojave Desert, an Upper Pleistocene deposit that produces abundant fossil remains from the silts and sands left behind by a great fresh water lake, roughly 350,000 to 19,000 years old--the Manix Beds yield many species of fresh water mollusks (gastropods and pelecypods), skeletal elements from fish (the Tui Mojave Chub and Three-Spine Stickleback), plus roughly 50 species of mammals and birds, many of which can also be found in the incredible, world-famous La Brea Tar Pits of Los Angeles.
  • Field Trip To Pleistocene Lake Manix, California: Go on a virtual field trip to the classic, fossiliferous badlands carved in the Upper Pleistocene Manix Formation, Mojave Desert, California. It's a special place that yields beaucoup fossil remains, including fresh water mollusks, fish (the Mojave Tui Chub), birds and mammals.
  • Trilobites In The Nopah Range, Inyo County, California: Travel to a locality well outside the boundaries of Death Valley National Park to collect trilobites in the Lower Cambrian Pyramid Shale Member of the Carrara Formation.
  • Ammonoids At Union Wash, California: Explore ammonoid-rich Union Wash near Lone Pine, California, in the shadows of Mount Whitney, the highest point in the contiguous United States. Union Wash is a ne plus ultra place to find Early Triassic ammonoids in California. The extinct cephalopods occur in abundance in the Lower Triassic Union Wash Formation, with the dramatic back-drop of the glacier-gouged Sierra Nevada skyline in view to the immediate west.
  • A Visit To The Fossil Beds At Union Wash, Inyo County California: A virtual field trip to the fabulous ammonoid accumulations in the Lower Triassic Union Wash Formation, Inyo County, California--situated in the shadows of Mount Whitney, the highest point in the contiguous United States.
  • Ordovician Fossils At The Great Beatty Mudmound, Nevada: Visit a classic 475-million-year-old fossil locality in the vicinity of Beatty, Nevada, only a few miles east of Death Valley National Park; here, the fossils occur in the Middle Ordovician Antelope Valley Limestone at a prominent Mudmound/Biohern. Lots of fossils can be found there, including silicified brachiopods, trilobites, nautiloids, echinoderms, bryozoans, ostracodes and conodonts.
  • Paleobotanical Field Trip To The Sailor Flat Hydraulic Gold Mine, California: Journey on a day of paleobotanical discovery with the FarWest Science Foundation to the western foothills of the Sierra Nevada--to famous Sailor Flat, an abandoned hydraulic gold mine of the mid to late 1800s, where members of the foundation collect fossil leaves from the "chocolate" shales of the Middle Eocene auriferous gravels; all significant specimens go to the archival paleobotanical collections at the University California Museum Of Paleontology in Berkeley.
  • Early Cambrian Fossils In Western Nevada: Explore a 518-million-year-old fossil locality several miles north of Death Valley National Park, in Esmeralda County, Nevada, where the Lower Cambrian Harkless Formation yields the largest single assemblage of Early Cambrian trilobites yet described from a specific fossil locality in North America; the locality also yields archeocyathids (an extinct sponge), plus salterella (the "ice-cream cone fossil"--an extinct conical animal placed into its own unique phylum, called Agmata), brachiopods and invertebrate tracks and trails.
  • Fossil Leaves And Seeds In West-Central Nevada: Take a field trip to the Middlegate Hills area in west-central Nevada. It's a place where the Middle Miocene Middlegate Formation provides paleobotany enthusiasts with some 64 species of fossil plant remains, including the leaves of evergreen live oak, tanbark oak, bigleaf maple, and paper birch--plus the twigs of giant sequoias and the winged seeds from a spruce.
  • Ordovician Fossils In The Toquima Range, Nevada: Explore the Toquima Range in central Nevada--a locality that yields abundant graptolites in the Lower to Middle Ordovician Vinini Formation, plus a diverse fauna of brachiopods, sponges, bryozoans, echinoderms and ostracodes from the Middle Ordovician Antelope Valley Limestone.
  • Fossil Plants In The Dead Camel Range, Nevada: Visit a remote site in the vicinity of Fallon, Nevada, where the Middle Miocene Desert Peak Formation provides paleobotany enthusiasts with 22 species of nicely preserved leaves from a variety of deciduous trees and evergreen live oaks, in addition to samaras (winged seeds), needles and twigs from several types of conifers.
  • Early Triassic Ammonoid Fossils In Nevada: Visit the two remote localities in Nevada that yield abundant, well-preserved ammonoids in the Lower Triassic Thaynes Formation, some 240 million years old--one of the sites just happens to be the single finest Early Triassic ammonoid locality in North America.
  • Fossil Plants At Buffalo Canyon, Nevada: Explore the wilds of west-central Nevada, a number of miles from Fallon, where the Middle Miocene Buffalo Canyon Formation yields to seekers of paleontology some 54 species of deciduous and coniferous varieties of 15-million-year-old leaves, seeds and twigs from such varieties as spruce, fir, pine, ash, maple, zelkova, willow and evergreen live oak
  • High Inyo Mountains Fossils, California: Take a ride to the crest of the High Inyo Mountains to find abundant ammonoids and pelecypods--plus, some shark teeth and terrestrial plants in the Upper Mississippian Chainman Shale, roughly 325 million years old.
  • Field Trip To The Copper Basin Fossil Flora, Nevada: Visit a remote region in Nevada, where the Late Eocene Dead Horse Tuff provides seekers of paleobotany with some 42 species of ancient plants, roughly 39 to 40 million years old, including the leaves of alder, tanbark oak, Oregon grape and sassafras.
  • Fossil Plants And Insects At Bull Run, Nevada: Head into the deep backcountry of Nevada to collect fossils from the famous Late Eocene Chicken Creek Formation, which yields, in addition to abundant fossil fly larvae, a paleobotanically wonderful association of winged seeds and fascicles (bundles of needles) from many species of conifers, including fir, pine, spruce, larch, hemlock and cypress. The plants are some 37 million old and represent an essentially pure montane conifer forest, one of the very few such fossil occurrences in the Tertiary Period of the United States.
  • A Visit To The Early Cambrian Waucoba Spring Geologic Section, California: Journey to the northwestern sector of Death Valley National Park to explore the classic, world-famous Waucoba Spring Early Cambrian geologic section, first described by the pioneering paleontologist C.D. Walcott in the late 1800s; surprisingly well preserved 540-510 million-year-old remains of trilobites, invertebrate tracks and trails, Girvanella algal oncolites and archeocyathids (an extinct variety of sponge) can be observed in situ.
  • Petrified Wood From The Shinarump Conglomerate: An image of a chunk of petrified wood I collected from the Upper Triassic Shinarump Conglomerate, outside of Dinosaur National Monument, Colorado.
  • Fossil Giant Sequoia Foliage From Nevada: Images of the youngest fossil foliage from a giant sequoia ever discovered in the geologic record--the specimen is Lower Pliocene in geologic age, around 5 million years old.
  • Some Favorite Fossil Brachiopods Of Mine: Images of several fossil brachiopods I have collected over the years from Paleozoic, Mesozoic and Cenozoic-age rocks.
  • For information on what can and cannot be collected legally from America's Public Lands, take a look at Fossils On America's Public Lands and Collecting On Public Lands--brochures that the Bureau Of Land Management has allowed me to transcribe.
  • In Search Of Vanished Ages--Field Trips To Fossil Localities In California, Nevada, And Utah--My fossils-related field trips in full print book form (pdf). 98,703 words (equivalent to a medium-size hard cover work of non-fiction); 250 printed pages (equivalent to about 380 pages in hard cover book form); 27 chapters; 30 individual field trips to places of paleontological interest; 60 photographs--representative on-site images and pictures of fossils from each locality visited.

United States Geological Survey Papers (Public Domain)

Online versions of USGS publications

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