| 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. |