--> Abstract: Foreland Basin Fills: What Controls Carbonate Versus Clastic Accumulation?, by David J. Gombosi, David L. Barbeau, and Christopher G. Kendall; #90078 (2008)

Datapages, Inc.Print this page

Foreland Basin Fills: What Controls Carbonate Versus Clastic Accumulation?

David J. Gombosi, David L. Barbeau, and Christopher G. Kendall
Geological Sciences, University South Carolina, Columbia, SC

Foreland basins are often associated with large orogenic hinterlands. Intuitively clastic sediments should fill them in response to high rates of sedimentation and increased accommodation space, but many foreland basins contain thick and/or widespread carbonate strata, raising the question what governs clastic versus carbonate domination?

First-order controls on rates of carbonate precipitation and accumulation include light penetration, temperature, oxygen availability, nutrient availability, ρCO2, salinity, accommodation, and faunal community. In contrast, clastic sedimentation is primarily driven by sediment supply.

Anecdotal evidence from modern analogues suggests controls work in tandem to determine the basinal lithologic fill. End member examples include the tropical, nutrient poor, low-turbidity, carbonate-rich Arabian Gulf and the tropical, nutrient-rich, moderately turbid, carbonate-poor Gulf of Carpentaria. They have similar temperature histories, pointing to other defining variables, e.g. nutrient flux, as deserving greater attention.

If modern controls extend to settings of the past do they explain how ancient end-members like the clastic dominated the Andean and Cordilleran foreland basin versus the carbonate dominated Tethyan foreland basin developed? By looking at settings of ancient carbonates we can examine long-term growth variables with small spatial variations but large temporal variations, e.g.: nutrients and/or ρCO2. For instance were nutrients carried by fluvial systems and/or oceanic circulation into foreland basins responsible for damping carbonate production in the clastic dominated Andean and Cordilleran chains? In contrast was the Arabian Plate’s Permian through Holocene carbonate production related to a lack of major fluvial input and reduction nutrient and sediment supply, or were other first-order controlling variables responsible?

 

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas