In Re: The Holocene Start Impact Event and on September 10, 2015, E.P. Grondine wrote
"Hi Paul- thanks for your note. Now, let me draw you a picture: http://archaeologica.boardbot.com/viewtopic.php?f=9&t=3656 " The in above web page among various stuff, you stated: "In the first of my notes, I speculated on the timing of the beginning of the Holocene Start Impact Event. In this note, I moved on to consider some possible physical evidence, and call attention to an earlier comment by David Ollen on the mechanics of large hypervelocity impacts onto ice sheet" This refers to an article "Did A Massive Meteor Touch Down Here" by By Graham Mason in the Lloydminster Meridian Booster, which is at: http://www.meridianbooster.com/2009/03/18/did-a-massive-meteor-touch-down-here In the past, you have asked for my comments on this feature, but I have been preoccupied with a geoarchaeological study of the Louisiana Continental Shelf and Slope for the Bureau of Ocean Energy Management, onshore geological mapping, and other projects. Having just got back from the field earlier than expected, I have had time to see what has been pubished about the geology of the Kitscoty, Alberta area in which this feature is located. Fortunately, there exist decent, detailed geological maps of that part of Alberta, e.g. Crickmay et al. (1942) and (Glombick 2014a, 2014b). Although there is an ovalish outcrop pattern, the comparison of these geological maps to local topographic maps found that this and other outcrop patterans are controlled by the local topography. The best that I can find, the local structure consists of gently dipping Cretaceous clastic strata that lack any discernable uplifts or any other structure that can be currently interpreted to be related to a major extraterrestrial impact. If a person looks hard enough anywhere in the world he or she can find any number of enigmatic circular, oval, circular and curvilinear features of uncertain origin illustrated in Gableman (1984) that are not related impact structures or craters. Of course, Gableman (1984) provides only one of many explantions offered for these still mysterious features. Buy the way, an interesting web page related to Alberta impact structures is: Cypress Hills region - Bedrock Geology and Physiography Astroblemes around the Cypress Hills (Eagle Butte structure) http://www.scirpus.ca/escape/scapebib/sect251.htm A recently published open-access and interesting paper related to the Younger Dryas is: Ancient Cold Period Could Provide Clues About Future Climate Change, University of Texas News, Sept. 2, 2015 http://news.utexas.edu/2015/09/02/ancient-cold-period-could-provide-clues-on-climate-change Partin,, J. W., T. M. Quinn, C.-C. Shen, Y. Okumura, M. B. Cardenas, F. P. Siringan, J. L. Banner, K. Lin, H.-M. Hu, and F. W. Taylor, 2015, Gradual onset and recovery of the Younger Dryas abrupt climate event in the tropics. Nature Communications 6, Article number: 8061 doi:10.1038/ncomms9061 Received 10 October 2014 Accepted 13 July 2015 Published 02 September 2015 Abstract at : http://www.nature.com/ncomms/2015/150902/ncomms9061/full/ncomms9061.html PDF at: http://www.nature.com/ncomms/2015/150902/ncomms9061/pdf/ncomms9061.pdf References Cited Crickmay, C. H., G. S. Hume, and C. O. Hage (1942) Kitscoty, Alberta. Geological Survey of Canada Map 673A. scale 1:253,440. Geological Survey of Canada/Department of Mines. Ottawa, Ontario, Canada. http://geoscan.ess.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/geoscanfastlink_e.web&search1=R=106804 http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/downloade.web&search1=R=106804 http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/geoscan_e.web Gableman, J. W. (1984) Circular Geomorphic Features Permissive to Interpretation as Conduits of Mantle Degasing. Global Tectonics and Metallogeny. vol. 2, nos. 3 and 4, pp. 151-168. Glombick, P. M. (2014a) Bedrock Geology of the Vermillion Area, Alberta (NTS 73E). AER/AGS Map 570. scale 1:250,000. Alberta Energy Regulator, Edmonton, Alberta, Canada. http://www.ags.gov.ab.ca/publications/abstracts/MAP_570.html http://www.ags.gov.ab.ca/publications/map/PDF/Map_570.pdf http://www.ags.gov.ab.ca/gis/ Glombick, P. M. (2014b) Bedrock Geology of the Wainwright Area, Alberta (NTS 73E). AER/AGS Map 569. scale 1:250,000. Alberta Energy Regulator, Edmonton, Alberta, Canada. http://www.ags.gov.ab.ca/publications/abstracts/MAP_569.html http://www.ags.gov.ab.ca/gis/ Yours, Paul H. ______________________________________________ Visit our Facebook page https://www.facebook.com/meteoritecentral and the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com https://pairlist3.pair.net/mailman/listinfo/meteorite-list