Dike diversity in the IODP-ICDP 364 core; a geochemical investigation into the Chicxulub impact structure

Online Access: Get full text
http://meetingorganizer.copernicus.org/EGU2018/EGU2018-8314.pdf
Author(s): de Graaff, Sietze J.; Kaskes, Pim; Vandijck, Ruben; Goderis, Steven; Claeys, Philippe
Author Affiliation(s): Primary:
Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-chemistry, Brussels, Belgium
Other:
Katholieke Universiteit Leuven, Belgium
Volume Title: European Geosciences Union general assembly 2018
Source: Geophysical Research Abstracts, Vol.20; European Geosciences Union general assembly 2018, Vienna, Austria, April 8-13, 2018. Publisher: Copernicus GmbH on behalf of the European Geosciences Union (EGU), Katlenburg-Lindau, Germany. ISSN: 1029-7006
Note: In English. 1 refs.
Summary: Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium The Chicxulub impact structure in Yucatan, Mexico is the only known terrestrial impact structure that is linked to an extinction event, has a global ejecta layer and preserves a distinct peak ring. This makes this structure a unique study area for both impact cratering processes and their environmental repercussions. The IODP-ICDP 364 Expedition in 2016 cored the peak ring of the Chicxulub crater, recovering 110 m of Paleogene sediments, 130 m of suevite and impact melt rocks, and 610 m of granitoid basement material [1]. The latter is intruded by both pre-impact magmatic dikes and impact melt rocks. These intrusions show large variations with aplite, pegmatite, dacite, felsite and dolerite, likely representing the pre-impact lithologies, and suevite and melt rocks representing the impact related lithologies [1]. This study presents preliminary results of petrographic thin section observations and major and trace element analyses using XRF, ICP-OES and LA-ICP-MS of these different types of intrusions within the granitoid basement succession. Using this data, we discuss the effects of the impact event on the pre-impact magmatic dikes and the geochemical characteristics and distribution of the suevite and impact melts throughout the granitoid basement. This approach provides further insight into the formational mechanics of the Chicxulub impact structure. [1] Morgan, J., Gulick, S., et al., 2017. Proceedings of the International Ocean Discovery Program, 364: College Station, TX (International Ocean Discovery Program). https://doi.org/10.14379/iodp.proc.364.2017 [Copyright Author(s) 2018. CC Attribution 4.0 License: https://creativecommons.org/licenses/by/4.0/legalcode]
Year of Publication: 2018
Research Program: IODP2 International Ocean Discovery Program
Key Words: 02 Geochemistry; 05 Petrology, Igneous and Metamorphic; Atlantic Ocean; Breccia; Cenozoic; Chemical composition; Chicxulub Crater; Cretaceous; Dikes; Expedition 364; Gulf of Mexico; ICP mass spectra; Impact breccia; Impact melts; Impactites; International Ocean Discovery Program; Intrusions; K-Pg boundary; Lower Paleocene; Major elements; Mass spectra; Melts; Mesozoic; Metamorphic rocks; North Atlantic; Optical spectra; Paleocene; Paleogene; Petrography; Spectra; Stratigraphic boundary; Suevite; Tertiary; Trace elements; Upper Cretaceous; X-ray fluorescence spectra
Coordinates: N212701 N212701 W0895658 W0895658
Record ID: 2018093348
Copyright Information: GeoRef, Copyright 2018 American Geosciences Institute. Reference includes data from European Geosciences Union, Munich, Germany