Global Paleobathymetry for the Cenomanian-Turonian (90 Ma)

Abstract:

We present a paleo-ocean bathymetry reconstruction for Cenomanian-Turonian (90 Ma) time in a 0.1°x0.1° resolution for use in paleo-climate studies. Age of the ocean floor for the Cenomanian-Turonian (90 Ma) is from Müller et al. (2008 a,b); coastlines are from the PALEOMAP Project (Scotese, 2011). To reconstruct paleo-ocean bathymetry, we use a plate model equation to model depth to basement (Turcotte and Schubert, 2002). We estimate plate model equation parameter values from measurements of modern oceans (Crosby et al., 2006). On top of the depth to basement, we isostatically add a multilayer sediment model derived from area-corrected sediment thickness data (Divins, 2003; Whittaker et al., 2013). Lastly, we parameterize the modern continental shelf, slope, and rise in a “sediment wedge model” to connect the coastline with the closest ocean crust as defined by Müller et al. (2008 a, b). These parameters are defined using empirical relationships obtained from study of modern ocean transects where a complete rifting history is preserved (Atlantic and Southern oceans), and the closest approach of the respective oceanic crust (Müller et al., 2008a,b) to the coastline. We use the modern ocean as a test, comparing maps and cross sections of modern ocean bathymetry modeled using our reconstruction method with that of ETOPO1 (Amante and Eakins, 2009). Adding sea plateaus and seamounts minimize the difference between our modeled bathymetry and ETOPO1. Finally, we also present a comparison of our reconstructed paleo-bathymetry to that of Müller et al. (2008 a,b) for the Cenomanian-Turonian (90 Ma).

References:

Amante, C., Eakins, B.W., 2009, NOAA Tech. Memo. NESDIS NGDC-24, 19 p.

Crosby, A., McKenzie, D., Sclater, J.G., 2006, Geophysical Journal Int. 166.2, 553-573.

Divins, D., 2003, NOAA NGDC, Boulder, CO.

Müller, R., Sdrolias, M., Gaina, C., Roest, W., 2008b, Geochemistry, Geophysics, Geosystems, 9, Q04006, doi:10.1029/2007GC001743

Müller, R., Sdrolias, M., Gaina, C., Steinberger, B., Heine, C., 2008a, Science, 319, 1357-1362.

Scotese, C., 2011, PALEOMAP Project, Arlington, Texas.

Turcotte, D., Schubert, G., 2002, Cambridge University Press, Cambridge, 456 p.

Whittaker, J., Goncharov, A., Williams, S., Müller, R., Leitchenkov, G., 2013, Geochemistry, Geophysics, Geosystems. DOI:10.1002/ggge.20181