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Badland topography, North San Juan. Altitude 1,800 feet. The material is decomposed granite, in situ, exposed by hydraulic mining. Nevada County, California: photo by G.K. Gilbert, 1905 (U.S. Geological Survey / U.S. Department of the Interior)
Badland topography, North San Juan. Altitude 1,800 feet. The material is decomposed granite, in situ, exposed by hydraulic mining. Nevada County, California: photo by Grove Karl Gilbert, 1905 (U.S. Geological Survey / U.S. Department of the Interior)
Badland topography, North San Juan. Altitude 1,800 feet. The material is decomposed granite, in situ, exposed by hydraulic mining. Nevada County, California: photo by Grove Karl Gilbert, 1905 (U.S. Geological Survey / U.S. Department of the Interior)
Badland topography, North San Juan. Altitude 1,800 feet. The material is decomposed granite, in situ, exposed by hydraulic mining. Nevada County, California: photo by Grove Karl Gilbert, 1905 (U.S. Geological Survey / U.S. Department of the Interior)
Smoke stratum, valley of Deer Creek at Nevada City. In the foreground is a pit from hydraulic mining. The smooth skyline marks a dissected plateau of andesitic lava. Nevada County, California: photo by Grove Karl Gilbert, 8 a.m., 28 October 1905 (U.S. Geological Survey / U.S. Department of the Interior)
Hydraulic mining pits at North Columbia, The pit in the foreground is known as "The Consolidated"; in the distance, at left, is the "Union Diggings"; at right the "Sailor Flat" nine. Nevada County, California: photo by Grove Karl Gilbert, n.d. (U.S. Geological Survey / U.S. Department of the Interior)
Tailings from hydraulic mining, Shady, near Patterson. The tailings were deposited in the creek valley as an alluvial fan, and were afterward partly eroded. Trees buried by the gravels were killed, but their stumps remained erect. Nevada County, California: photo by Grove Karl Gilbert, 1909 (U.S. Geological Survey / U.S. Department of the Interior)
Tailings from hydraulic mining, Shady Creek, near Patterson. The tailings were deposited in the creek valley as an alluvial fan, and were afterward partly eroded. Trees buried by the gravels were killed, but their stumps remained erect. Nevada County, California: photo by Grove Karl Gilbert, 1909 (U.S. Geological Survey / U.S. Department of the Interior)
Tailings from hydraulic mining, Shady Creek, near Patterson. The tailings were deposited in the creek valley as an alluvial fan, and were afterward partly eroded. Trees buried by the gravels were killed, but their stumps remained erect. Nevada County, California: photo by Grove Karl Gilbert, 1909 (U.S. Geological Survey / U.S. Department of the Interior)
Earthflow at Blue Tent, A field, supposed to have been previously smooth, is thrown into undulation by a general flow of underlying gravels, the flow being occasioned by hydraulic mining. Nevada County, California: photo by Grove Karl Gilbert, 1909 (U.S. Geological Survey / U.S. Department of the Interior)
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