Field and computer modeling studies of Appalachian cyclic carbonates

Conference · Mon Feb 01 04:00:00 EST 1988 · AAPG Bull.; (United States)

OSTI ID:6015261

Read, J F

Cyclic carbonates in the Cambrian of the Appalachians have been studied using field data integrated with computer modeling studies. The models incorporate 1 to 3-m.y. and 20,000 to 100,000-year low-amplitude sea level fluctuations, water depth-dependent sedimentation rates, lag time, and subsidence. The 1 to 3-m.y. sea level fluctuations are defined by Fischer plots, which are readily compared to the model output. Cycles decrease in number toward regional highs, because (1) lower subsidence rates only allow 40 to 60% of the Milankovitch sea level fluctuations to affect the highs and (2) highs subside lower than third-order sea levels fall, which truncate 50% of cycles. Furthermore, 2 cycles/100,000 years are deposited on the outer shelf, compared to 1 to 1.4 cycles/100,000 years on inner shelf highs. Consequently cycles have longer average periods toward the highs. Furthermore, average thickness shows only a slight decrease landward, even though formation thicknesses may be halved. The field data and modeling constrain amplitudes of 1 to 3-m.y. sea level changes because significant unconformities are absent from the shelf sequence, indicating third-order sea levels fell slower than subsidence rates, thus were considerably less than 50 m.

• Research Organization: Virginia Polytechnic Institute and State Univ., Blacksburg (USA)
• OSTI ID: 6015261
• Report Number(s): CONF-880301-
• Conference Information: Journal Name: AAPG Bull.; (United States) Journal Volume: 72:2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
APPALACHIAN MOUNTAINS
CARBONATE ROCKS
COMPUTERS
DEPOSITION
GEOLOGIC MODELS
MATHEMATICAL MODELS
MOUNTAINS
ROCKS
SEDIMENTARY ROCKS