Ramps and Flats – Definition
Ramps and flats are characteristic of a thin-skinned thrust fault geometry, and they form a step-like pattern. Flat are fault surfaces that form parallel to the strata and usually in weak rock units, such as evaporites and shales. Ramps cut across more resistant rock units, for example sandstone and limestone, forming a dip angle that is typically 30 to 45 degrees.
Ramps and flats are characteristic of a thin-skinned thrust fault geometry, and they form a step-like pattern. Flat are fault surfaces that form parallel to the strata and usually in weak rock units, such as evaporites and shales. Ramps cut across more resistant rock units, for example sandstone and limestone, forming a dip angle that is typically 30 to 45 degrees.