[meteorite-list] Unconventional Meteorite Hunting - Example from Sweden
From: Paul <lenticulina1_at_meteoritecentral.com>
Date: Thu Apr 22 10:28:19 2004 Message-ID: <20031002024055.89580.qmail_at_web21402.mail.yahoo.com> It seems like there are some unconventional places that people can look for meteorites. For example, ancient meteorites have been found in the carbonate rocks of Sweden as discussed in: Schmitz, B. Peucker-Ehrenbrink, Lindstrom, M., and Tassinari, M., 1997, Accretion Rates of Meteorites andCosmic Dust in the Early Ordovician. Science. vol. 278, no. 5335, pp. 88-90. In this paper they discussed "Abundant fossil meteorites" that were found in "...marine, condensed Lower Ordovician limestones..." They note: 1. A 4-inch in diameter meteorite discovered middle Ordovician Limestone in 1951, which was described by Thorslund and Wickman (1981). 2. a swedish meteorite , called "Osterplana 1," which was discovered in 5-million year older Lower Ordovician limestone about 300 miles away from the above by Hansen and Berstrom (1997). Twelve more meteorites have been found at the Thorsberg Limestone Quarry. Hansen and Berstrom (1997, pp. 3) stated: "A 10-foot-thick section of the Holen ("Orthoceratite") Limestone, of Early Middle Ordovician age, is extracted at the Thorsberg quarry and sawed into thin slabs that are used for windowsills and floor tile. Quarry workers discarded slabs with impurities, such as the meteorites, until Professor Maurits Lindstrom of the University of Stockholm alerted them to save such slabs. The 12 specimens were recovered between 1992 and 1996. Ten of the specimens were recovered from a 2-foot-thick bed of limestone and may represent a single meteorite fall. The other three specimens were recovered from two separate levels above this layer. Seven of the specimens, collected between 1993 and 1996, are from a quarried limestone volume of no more than about 127,000 cubic feet. Most of the specimens are now on display at the Stiftelsen Paleo Geology Center in Lidkoping, Sweden." The meteorites found in the Thorsberg Quarry meteorites range in size from about 0.5 to 3.5 inches in diameter. They have been almost completely replaced by calcite and barite. The meteorite masses are dark reddish brown and look like iron nodules surrounded by a zone of lighter colored limestone. It would be fun to look at correlative condensed sections, in the United States and elsewhere for similar fossil meteorites. If there was a period of increased meteorite influx during the Ordovician, meteorites should findable in the Untied States as well as Sweden. Additional and Cited References Hasen, M. C., and Bergstrom, S. M.. 1997, Ancient meteorites. Ohio Geology, Spring 1997. Nystrom, J. O., and Wickman, F. E., 1991, The Ordovician chondrite from Brunflo, central Sweden; II, Secondary minerals. Lithos. vol. 27, no. 3, pp. 167-185. Nystrom, J. O., Lindstrom, M., and Wickman, F. E., 1988, Discovery of a second Ordovician meteorite using chromite as a tracer. Nature. vol. 336, pp. 572-574. Schmitz, B., Lindstrom, M., Asaro, F., and Tassinari, M., 1996, Geochemistry of meteorite-rich marine limestone strata and fossil meteorites from the Lower Ordovician at Kinnekulle, Sweden. Earth and Planetary Science Letters. vol. 145, pp. 31-48. Thorslund, Per, and Wickman, F. E., 1981, Middle Ordovician chondrite in fossiliferous limestone from Brunflo, central Sweden. Nature. vol. 289, pp. 285-286. Thorslund, Per., Wickman, F. E., and Nystrom, J. O., 1984, The Ordovician chondrite from Brunflo, central Sweden, I. General description and primary minerals. Lithos. vol. 17, pp. 87-100. Another person, Andrew A. Sicree of the Earth and Mineral Sciences Museum at Pennsylvania State University is looking for meteorites in coal deposits. Web pages and pdf files discussing his efforts can be found at: FINDING FOSSIL METEORITES: http://www.meteorite.com/psu_find.htm Researchers Seek Meteorites In Coal Mines http://www.psu.edu/ur/NEWS/SCIENCETECH/meteorite.html POTENTIAL FOR PRESERVATION AND RECOVERY OF FOSSIL IRON METEORITES FROM COAL, TRONA, LIMESTONE, AND OTHER SEDIMENTARY ROCKS. http://www.lpi.usra.edu/meetings/metsoc97/pdf/5057.pdf There are likely various unorthodox places where people might hunt for meteorites. Yours, Paul Baton Rouge, LA __________________________________ Do you Yahoo!? The New Yahoo! Shopping - with improved product search http://shopping.yahoo.com Received on Wed 01 Oct 2003 10:40:55 PM PDT |
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