Deep geometry of the Sudbury structure from seismic reflection profiling

Abstract

Research Article| September 01, 1992 Deep geometry of the Sudbury structure from seismic reflection profiling B. Milkereit; B. Milkereit 1Geological Survey of Canada, Ottawa, Ontario K1A 0Y3, Canada Search for other works by this author on: GSW Google Scholar A. Green A. Green 1Geological Survey of Canada, Ottawa, Ontario K1A 0Y3, Canada Search for other works by this author on: GSW Google Scholar Geology (1992) 20 (9): 807–811. https://doi.org/10.1130/0091-7613(1992)020<0807:DGOTSS>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 MailTo Tools Icon Tools Get Permissions Search Site Citation B. Milkereit, A. Green; Deep geometry of the Sudbury structure from seismic reflection profiling. Geology 1992;; 20 (9): 807–811. doi: https://doi.org/10.1130/0091-7613(1992)020<0807:DGOTSS>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 Seismic reflection data show the deep geometry of the Sudbury structure to be markedly asymmetric. The Sudbury North Range comprises shallowly south dipping sedimentary strata overlying a thick unit of heterolithic breccia and melt bodies, layered rocks of the Sudbury igneous complex, and footwall gneiss. Reflections from the upper layers are interrupted by faults near the center of the Sudbury basin, whereas the basal mafic units and footwall gneiss continue dipping southward and appear to be tightly folded or truncated near the Creighton fault. In contrast, the seismic image of the South Range is dominated by a distinctive series of moderately south dipping reflections interpreted as thrust faults or shear zones on which severe telescoping and imbrication of lithological units and considerable northwest-southeast shortening of the Sudbury structure have occurred. Such shortening explains the noncircular shape of the structure, and thus removes a critical objection to the Sudbury impact crater hypothesis. The new structural model is shown to be consistent with regional magnetic and gravity fields; a large hidden ultramfic-mafic mass is no longer required to explain the potential field data. 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.