The ICDP-USGS Deep Drilling Project in the Chesapeake Bay impact structure : results from the Eyreville core holes

0341087 - GLÚ 2010 RIV US eng M - Monography Chapter
Skála, Roman - Langenhorst, F. - Deutsch, A.
Geochemical characteristics of basement target rocks, suevitic glasses from the Eyreville B drill core, Chesapeake Bay impact structure, and three bediasites.
The ICDP-USGS Deep Drilling Project in the Chesapeake Bay impact structure : results from the Eyreville core holes. Boulder: Geological Society of America, 2009 - (Gohn, G.), s. 435-445. Special papers of the Geological Society of America. ISBN 978-0-8137-2458-4
Institutional research plan: CEZ:AV0Z30130516
Keywords : Chesapeake Bay impact crater * Eyreville B core hole * impact glasses * bediasites * tektites * geochemistry
Subject RIV: DD - Geochemistry

The ICDP–USGS Eyreville B core hole sampled the 35.5-Ma-old Chesapeake Bay impact crater, Virginia. Chemical analyses of impact glasses, crystalline target rocks, and bediasites allowed better constraining of the precursor materials of glasses as well as of the bediasites. Statistical treatment diveded the data for the crystalline basement samples into four groups; two of those (various schists, meta-graywackes, and gneisses) display characteristics similar to the impact glasses in the suevites and the bediasites. The suevitic glasses show a broad range in composition at the micrometer scale. These data show the frequent presence of schlieren, and in particular, enhanced TiO2 contents that require admixture of an “amphibolitic component” to the melt. The three studied bediasites show only minor inter- and intrasample heterogeneity. The new data for the bediasites are compatible with heating of the “tektite melt” to extreme temperatures, followed by rapid quenching.
Permanent Link: http://hdl.handle.net/11104/0184181