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The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 63 (1979)

Issue: 3. (March)

First Page: 529

Last Page: 529

Title: Tertiary Sea-Level Movements Around Southern Africa: ABSTRACT

Author(s): William G. Siesser, Richard V. Dingle

Article Type: Meeting abstract

Abstract:

Sedimentologic, micropaleontologic, and seismic-profiling data elucidate the history of Tertiary sea-level movements around southern Africa. These new data show that landward movement of the sea began in early late Paleocene time and continued into the early Eocene. The sea probably reached its maximum Paleogene height during the early Eocene, and is today represented by outcrops up to at least 204 m, and probably as high as 360 m, above sea level. A brief regressive pulse occurred during the middle Eocene, and renewed transgression in the late Eocene. A major regression followed, spanning all of Oligocene and early Miocene times. This regression exposed much of the continental shelf. It is clearly represented on seismic-reflection profiles as a widespread unconformity. >

The major Neogene transgression began in the middle Miocene but probably only reached the present coastline by late Miocene time. This transgression continued into the early Pliocene, but was interrupted by a brief regressive pulse in the earliest Pliocene. Seas withdrew again in the late Pliocene. Units deposited during the Miocene-Pliocene transgression are today found up to at least 300 m above sea level.

This scheme should be viewed as showing only the gross movements of the seas around southern Africa during the Tertiary. Local subsidence or uplift may have caused one area of the coast to submerge or emerge earlier than another area. Nevertheless, the timing of these southern African transgressions and regressions closely parallels the timing recently established for sea-level movements in other parts of the world.

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Copyright 1997 American Association of Petroleum Geologists