Weathering rind in basaltic rock.

All rocks at Earth's surface are prone to chemical attack--and as can be expected, most chemical weathering occurs on the exposed outer edges of rock. When broken, many rocks show "weathering rind", an outer edge of material that is noticeably more chemically weathered than the inside of the rock.
Precambrian ripple marks

Back to Miscellaneous Geology Images
Back to Geology Photos