Tertiary sea-level fluctuation in South Carolina

Abstract

Recognition of physical, chemical, and biotic parameters associated with cyclic formations allows determination of former marine fluctuation. It is possible to observe major sea-level changes from at least the Late Miocene to the Recent with respect to the Atlantic coastal plain and to infer relative changes of sea level in earlier Tertiary time. The following major fluctuations are indicated: ( 1) sea-level rise in Cretaceous and relative stability through Early Eocene (Black Mingo) time; ( 2) sea-level fall in pre-Claiborne; ( 3) sea-level rise in Claiborne (Congaree, McBean, and Santee) and relative stability through Late Eocene (Barnwell), Oligocene (Cooper), and Early and possibly Median Miocene (Hawthorne) time; evidence of a change from warm pre-Oligocene seas to cooler waters during Oligocene and through Early and possibly Median Miocene; tectonic warping during this Oligocene-Median Miocene interval; ( 4) sea-level fall; ( 5) sea-level rise to at least 190 ft. in warm climate in Late Miocene (Duplin) time; ( 6) slow sea-level fall with prograding 3lluvial fans-deltas? to possibly less than 140 ft. in Late Miocene?-Pliocene?; ( 7) pause or rise to 140 ft. and formation of Parler Scarp during Late Miocene?- Pliocene?; ( 8) sea-level fall; ( 9) pause at 100 ft. or possible lower fall and rise to 100 (circa) ft.; formation of Surry Scarp (Pleistocene); ( 10) sea-level fall to less than 0 ft. with pause at 70 ft.; and ( 11) sea-level rise to 45 ft. (Sangamon). The Pliocene-Pleistocene boundary must lie between the cutting of the Parler Scarp and the formation of the Wicomico terrace (100 + ft. or less) and may be represented by the regression to 100 ft. or to a stand below 100 ft. and return.