Impact dust not the cause of the Cretaceous-Tertiary mass extinction

Research Article| February 01, 2002 Impact dust not the cause of the Cretaceous-Tertiary mass extinction Kevin O. Pope Kevin O. Pope 1Geo Eco Arc Research, 16305 St. Mary's Church Road, Aquasco, Maryland 20608, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Kevin O. Pope 1Geo Eco Arc Research, 16305 St. Mary's Church Road, Aquasco, Maryland 20608, USA Publisher: Geological Society of America Received: 11 May 2001 Revision Received: 10 Sep 2001 Accepted: 02 Oct 2001 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2002) 30 (2): 99–102. https://doi.org/10.1130/0091-7613(2002)030<0099:IDNTCO>2.0.CO;2 Article history Received: 11 May 2001 Revision Received: 10 Sep 2001 Accepted: 02 Oct 2001 First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Kevin O. Pope; Impact dust not the cause of the Cretaceous-Tertiary mass extinction. Geology 2002;; 30 (2): 99–102. doi: https://doi.org/10.1130/0091-7613(2002)030<0099:IDNTCO>2.0.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 Most of the 3-mm-thick globally distributed Chicxulub ejecta layer found at the Cretaceous-Tertiary (K-T) boundary was deposited as condensation droplets from the impact vapor plume. A small fraction of this layer (<1%) is clastic debris. Theoretical calculations, coupled with observations of the coarse dust fraction, indicate that very little (<1014 g) was submicrometer-size dust. The global mass and grain-size distribution of the clastic debris indicate that stratospheric winds spread the debris from North America, over the Pacific Ocean, to Europe, and little debris reached high southern latitudes. These findings indicate that the original K-T impact extinction hypothesis—the shutdown of photosynthesis by submicrometer-size dust—is not valid, because it requires more than two orders of magnitude more fine dust than is estimated here. Furthermore, estimates of future impact hazards, which rely upon inaccurate impact-dust loadings, are greatly overstated. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.