Shocked quartz from the late Eocene: Impact evidence from Massignano, Italy

Abstract

Research Article| June 01, 1996 Shocked quartz from the late Eocene: Impact evidence from Massignano, Italy Aron K. Clymer; Aron K. Clymer 1Department of Geology and Geophysics, University of California, Berkeley, California 94720-4767 Search for other works by this author on: GSW Google Scholar David M. Bice; David M. Bice 2Department of Geology, Carleton College, Northfield, Minnesota 55057 Search for other works by this author on: GSW Google Scholar Alessandro Montanari Alessandro Montanari 3Osservatorio Geologico di Coldigioco, 62020 Frontale (MC), Italy, and École des Mines de Paris, France Search for other works by this author on: GSW Google Scholar Author and Article Information Aron K. Clymer 1Department of Geology and Geophysics, University of California, Berkeley, California 94720-4767 David M. Bice 2Department of Geology, Carleton College, Northfield, Minnesota 55057 Alessandro Montanari 3Osservatorio Geologico di Coldigioco, 62020 Frontale (MC), Italy, and École des Mines de Paris, France Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1996) 24 (6): 483–486. https://doi.org/10.1130/0091-7613(1996)024<0483:SQFTLE>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Aron K. Clymer, David M. Bice, Alessandro Montanari; Shocked quartz from the late Eocene: Impact evidence from Massignano, Italy. Geology 1996;; 24 (6): 483–486. doi: https://doi.org/10.1130/0091-7613(1996)024<0483:SQFTLE>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract This paper reports the discovery of shocked quartz grains within a well-dated upper Eocene marlstone at the Massignano outcrop (Ancona, Italy). The shocked quartz reaches a maximum concentration of 1.6 ± 0.4 grains per cubic centimetre of bulk rock. A modest Ir anomaly is also coincident with the shocked quartz, and together they strongly support an impact origin. Moreover, this impact layer has a precise interpolated radiometric age of 35.7 ± 0.4 Ma. Although impact evidence found throughout the world indicates that at least two large impacts did occur during this time, the actual number, timing, and environmental effects of these impact events remain unclear. The late Eocene was a critical time in Earth history because of significant climatic, biotic, and environmental crises. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.