59. Throughout the southeastern United States, which has a warm, humid climate, there are many features caused by severe chemical weathering. These features can mimic those of seismic liquefaction origin. Mimics have formed in deposits as young as several tens of thousands of years. (Liquefaction features in South Carolina commonly occur in deposits as old as 100,000 to 200,000 years.) The sediments hosting the weathering features are generally silty or clayey sand, and the sand is nearly all quartz.

This photograph shows white, clean zones of sand throughout a clayey sand deposit (blue and yellow-brown). Chemical weathering has destroyed the clay, and leaching of the weathered products has left behind clean sand zones.