Mid-Piacenzian generalized marine environment

An illustration of a generalized Mid-Piacenzian marine environment 

Detailed Description

Mid-Piacenzian generalized marine environment. PRISM archives include (1) deep-sea cores and (2) outcrops on land. Palaeoenvironments sampledrange from (3) shelf to (4) open-ocean and (5) deep-ocean bottom. Signal carriers include (a) planktonic and (b) benthic foraminifers, (c) ostracods, (d) diatoms, (e) calcareous nannoplankton, (f) radiolaria, (g) dinoflagellates, (h) picoplankton, (i) mollusks and (j) bryozoa. Fish teeth (also used as signal carriers) are not figured. Quantitative analysis of planktonic and benthic foraminifer, diatom, radiolaria and dinoflagellate assemblages provide SST, shallow bottom water temperature (SBT), productivity, salinity and sea ice distribution. Calibrated biomarker molecules derived from nanno- and picoplankton provide additional SST information. Macro invertebrate assemblages provide semi quantitative estimates of SBT and mean annual range in temperature (MART). Oxygen isotopic analysis of mollusks allows for seasonality estimates. Mg/Ca analysis of planktonic and benthic foraminifers establishes independent SST, SBT and deep ocean temperature (DOT). Paired Mg/Ca and oxygen isotopic analyses on deep ocean benthic foraminifers and ostracods allow for sea level and global ice volume estimates. Analysis of stable carbon isotopes on benthic foraminifers and Nd derived from fish teeth provide estimates of paleocirculation. An increased understanding of the timing and variability of production of these signal carriers and knowledge of their environmental preferences (e.g. depth habitat) provide a means of analyzing upwelling systems and constraining circulation (shown by arrows).


Dowsett, H. J., Robinson, M. M., Stoll, D. K., Foley, K. M., Johnson, A. L. A., Williams, M., and Riesselman, C. R.: The PRISM (Pliocene Palaeoclimate) reconstruction: Time for a paradigm shift, Philosophical Transactions of the Royal Society, 371, 1-24, 2013.


Image Dimensions: 1736 x 1420

Date Taken:

Location Taken: US