ISOSTATICALLY CORRECTED MODELED MULTILAYER SEDIMENT COVER FOR GLOBAL PALEOBATHYMETRY RECONSTRUCTION WITH IMPROVED PARAMETERIZATION USING VARYING SEDIMENT DENSITIES FROM OCEAN DRILLING PROGRAM(S)

OES paleobathymetry reconstruction methodology combines a simple standard geophysical plate cooling model (depth-to-basement) based on the published ages of the oceanic crust, modeled global oceanic sediment thicknesses, and a generalized sediment wedge model (SWM) representing continental shelf-slope-rise (SSR) structures calibrated at modern heterogeneous continental margins, both active and passive types. On top of this depth-to-basement, a modeled multilayer sediment layer is added isostatically, typically derived from area-corrected published global sediment thickness data. In this study we are presenting a prudent parameterization method for this modeled oceanic sediment thickness layer replacing the previously used very simple linear extrapolation of sediment densities with 100 m increments, calibrated from 10 different published sediment densities.

The parameters for this updated sediment model are calculated using empirical relationships between the underlying crustal age, water depth, location of carbonate compensation depth, distance from land, predicted sediment types (namely terrigenous, clay-rich, and/or calcareous-rich) and corresponding individual sediment type densities. The sediment densities are again entirely recalibrated using a database of published sediment densities, with more than 45,000 records, mainly obtained from the DSDP, ODP and IODP publications.

The difference between the old and new update modeled sediment layer is presented here, along with the sediment density database, for at least two different geological time intervals, the Cenomanian-Turonian Boundary (94 Ma) and Paleocene-Eocene Thermal Boundary (56 Ma); for which currently we are reconstructing updated paleobathymetry.