The snow-capped northern Sierra Nevadas are featured in this low-oblique, northeast-looking, synoptic photograph. The Sierra Nevadas, the largest tilted fault block structure in the United States, provide snowmelt to the Sacramento Valley for irrigation. Visible are dark blue Lake Tahoe, a deep basin within the Sierra Nevadas, near the center right and light blue Pyramid Lake, named for the large pyramidal rocks surrounding it, to the north and east of Lake Tahoe. Viewing from Pyramid Lake are the north-south-trending Warner Mountains to the north-northwest; the dry, alkaline lakes of Smoke Creek Desert and Black Rock Desert to the north; and white, marshy Carson Sink to the east.