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University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies Legacy Theses 2000 The seismic characterization of meteorite impact structures Mazur, Michael James Mazur, M. J. (2000). The seismic characterization of meteorite impact structures (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/18283 http://hdl.handle.net/1880/39754 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca THE UNIVERSITY OF CALGARY The Seismic Characterization of Meteorite Impact Structures by Michael James Mazur A THESIS SUBMITIED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE DEPARTMENT OF GEOLOGY AM)GEOPHYSICS CALGARY, ALBERTA AUGUST, 1999 O Michael James Mazur 1999 National Library BiMioth&que nationale du Canada Acquisitions and Acquisitions et Bibliographic Services services bibliographques 395 Wellingtorr Street 395. nm WdlingtOrr Ottawa ON KIA ON4 -ON KYAON4 carlada Canada The author has granted a non- L'auteur a accorde une licence non exclusive licence allowing the exclusive permettant a la National Library of Canada to Bibliotheque nationale du Canada de reproduce, loan, distribute or sell reproduire, pr&ter,distribuer ou copies of this thesis in microform, vendre des copies de cette these sous paper or electronic formats. la fonne de microfiche/film, de reproduction sur papier ou sur format electronique. The author retains ownership of the L'auteur conserve la propriete du copyright in this thesis. Neither the droit d'auteur qui protege cette these. thesis nor substantial extracts fiom it Ni la these ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent &re imprimes reproduced without the author's ou autrement reproduits sans son permission. autoriation. University of Calgary Abstract The Seismic Characterization of Impact Structures by Michael James Mzur This thesis examines the seismic characteristics of three possible impact craters and one confirmed impact structure. Using established seismic methods and impact crater scaling relations, an investigation of these features is undertaken. The largest structure examined here is the 24-km diameter Steen River impact feature in northwestern Alberta, Canada This astrobleme has been imaged by more than 130 seismic lines to date. The second largest structure studied in this thesis is the 3.5-km Hotchkiss structure located approximately 300-km south of the Steen River impact structure. The three seismic lines imaging this feature clearly show many of the diagnostic features of a complex impact feature. The Muskingum structure in Ohio, USA is approximateIy 1.3 krn across and possibly represents an impact crater within the simple-tocomplex transition zone. The 2- km diameter Puffin structure is apparent on a 3-D seismic dataset acquired in the Timor Sea off the coast of northwestern Australia. Interpretation of this structure is inherently complex and indefinite due to extensive faulting in the area and due to the proximity of several kimberlite pipes to the study area. TABLE OF CONTENTS LIST OF FIGURES.......)... .......... .... ............... ............... .....-............. ....Hn.H-- ..............H....H......l...mH........ W LIST OF TABLES...... ,...~....~.~..H......~-m..m.~.n-........H..n~n........ ..........&..*.. ...................................... .-.OH ACKNOWLEDGMENTS ....,. .........., ..)......n...m.....H-......).................. ....... )................ X GLOSSARY .................,...,............................................)......................... INTRODUCTION TO THE STUDY OF IMPACT STRUCTURES...... .,..-. ..... .......................- ..... 1 1.1 THE HISTORY OF IMPACT CRATER STUDIES .................................................................................................. 1 f .2 TERRESTRIALIMPACT CRATER STUDIES ...................................................................................................... 3 I .3 IMPAC~CRATER TYPES ................................................................................................................................. 5 1.4 ECONOMIC[MPORTANCE OF IMPACT STRUCIWRES ...................................................................................... 8 1 -5 OTHER CRATER-LLKEFEATURES .................................................................................................................. 9 PHYSICS OF IMPACT CRATERJNG... ). ...... .. .....,....... .., ................................................................. ..,.. 11 2.1 STRESSES.LIMITS. AND HUGONIOTCURVES ............................................................................................ 11 2.2 THE THREE STAGES OF IMPAn.................................................................................................................. 15 2.3 VERTICALAND OBLIQUE IMPACTS ............................................................................................................ 16 2.4 STRUCIURED TARGETS .............................................................................................................................. 18 2.5 SCALINGOF CRATER DIMENSIONS........................................................................................................... 20 SIMPLE IMPACT STRUCTURES ....................................................... ....................... 23 3.1 PUFFIN3.D. NW AUSTRALIA.................................................................................................................... 23 3.1. I Geological Setting ......................................................................................................... .. .................. 23 3.1.2 Seismic Data /nterpretation .................................................................................. ,. ....................... 21 3.1.3 Impact Crater Morphomerry ............................................................................................................. 25 3.1.4 Other Possible Eiplanatiom ............................................................................................................. 28 3.1.5 Concluding Remarks ..................... ,... ........................................................................................ 29 3.2 MUSKBGWM.OHIO .................................................................................................................................... 46 3.2.1 Geological Setting ............................................................................................................................. 46 3.2.2 Geopl~ysicalCha racte risrics .................................................................. ... .. 47 3.2.3 Seismic Data Interpretatiorr ....................... ,. ................................................................................. 47 3.2.4 Morphometry .................................................................................................................................... 48 3.2.5 Other Possible Explanations ............................ ............................................................................... 51 3.2.6 Age of the Muskingum Strucurre ..................................................................................................... 52 3.2.7 Concluding Remarks ......................................................................................................................... 53 COMPLEX IMPACT STRUCTURES ...,me. ). ...ere. ......~..~.......................................... 0.G 4.1 HOTCHKISS.ALBERTA ............................................................................................................................. 65 3.1.I Geological Setting ............................................................................................................................. 65 4.1.2 Geophysical Characteristics .................................... ,... ..................................................................... 66 4.1.3 Seismic Data Interpretation .............................................................................................................. 68 4.1.4 Morphomerry ..................................................................................................................................... 70 4.1.5 Concluding Remarks ......................................................................................................................... 72 4.2 STEEN RIVER, ALBERTA ............................................................................................................................ 84 4.1.1 Geological Setting ........................................................................................................................... 84 ... 4.1.2 Interpretation of the Sersmrc Time Sections...................................................................................... 85 4.1.3 Observations..................................................................................................................................... 86 4.1.4 Time-to-depth Conversion using Petrosys ........................................................................................ 87 4.1.5 Depth Conversion using GeoStat .....................................................................................................
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