Geology Commons^™

Orbitally Paced Shifts In The Particle Size Of Antarctic Continental Shelf Sediments In Response To Ice Dynamics During The Miocene Climatic Optimum, Sandra Passchier, Candice J. Falk, Fabio Florindo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The AND-2A drill hole (ANDRILL [Antarctic Geological Drilling Program] Southern McMurdo Sound Project), ∼10 km from the East Antarctica coastline, records nearly 6 m.y. of sedimentation across the Miocene climatic optimum at a high-latitude site. Sedimentological studies of bedforms and particle size distributions indicate that the paleoenvironment was strongly affected by waves and currents, consistent with deposition in a glacially influenced neritic environment. We document abrupt shifts in mud percent within glacial-interglacial cycles ca. 17.8 Ma and between ca. 16.7 and 15.7 Ma that we attribute to the hydrodynamic effects of wave stirring tied to episodes of ice growth and …