1.4 Billion Year Old Felsic Pegmatite along US-93 west of Nothing, AZ - Geology Road Stop скачать в хорошем качестве

1.4 Billion Year Old Felsic Pegmatite along US-93 west of Nothing, AZ - Geology Road Stop

A spontaneous geology road stop while driving on US-93 near Nothing, Arizona. I describe the rocks as quartz monzonite because they look quite similar to those rocks found at Joshua Tree National Park. The rocks are officially mapped as granite and pegmatite granite. I mention intrusions and veins of mostly quartz, and those are officially mapped as aplite. See geologic map info below. GPS Coordinates: 34.484467, -113.361164 Geologic Map Description: "Mostly porphyritic biotite granite with large microcline phenocrysts, with local fine-grained border phases and aplite. Associated pegmatite and quartz veins are rare. This unit forms large plutons, including the Oracle Granite, Ruin Granite, granite in the Pinnacle Peak - Carefree area northeast of Phoenix, and several bodies west of Prescott. (1400-1450 Ma)" Citation: Horton, J.D., C.A. San Juan, and D.B. Stoeser, 2017, The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States: U.S. Geological Survey Data Series 1052, doi: 10.3133/ds1052.133 / 2932719