Gold Is Where You Find It

[HardPack]

I have read what remains of the Sierra Nevada Mountains is what exceeded the rate of erosion over the geologic time period of their existence. Prior to the uplift of the mountains there were approximately 20 miles of sedimentary and metamorphic deposits capping the granite batholiths that would form the base of the future mountain range. 55 million years ago meandering down an uplifting western drainage slope flowed several ancient rivers draining a plateau to the east that reached into central and eastern Nevada, These ancient rivers flowed through broad river valleys as they crossed the ancient plateau cutting through multiple gold bearing fault zones. As these rivers flowed down the western slope their currents curved through yet more gold bearing fault zones along the lower western edge of the drainage slope. Sediments and gold bearing gravels carried by these rivers were deposited along the banks of the ancient rivers and eventually as fans along the western edge of the drainage slope. In time the ancient plateau would extend into the basin and range complex. The western drainage slope would continue to uplift forming the Sierra Nevada mountain range. More recent rivers would head at the Sierra summits cutting different channels often through the ancient river channels robbing their beds of its ancient gold deposits. During the multiple ice ages glaciers continued to grind the mountains down to their granite core. Melt water from the glaciers would saturate the western sediment basin that filled the Central Valley. Yet today the mountain summits far exceed 10,000 feet and continue to climb. The river sediments that are not carried to the ocean continue to fill the basin to the west as deep as the mountains are tall. 

Although another range of mountains carrying sediments to the east Myron Cook, a geologist, demonstrates the scale of erosion that has occurred through the ages.