Download or read book Geology of National Parks written by Ann G. Harris and published by Kendall Hunt. This book was released on 2004 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt: CD-ROM contains: Introductory text, maps, and geologically labeled photographs of all the parks.

Download or read book U S Geological Survey Bulletin written by and published by . This book was released on 1983 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Professional Paper written by and published by . This book was released on 1984 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 1992 Mineral Frontiers on Indian Lands written by and published by . This book was released on 1992 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Great Lakes Tectonic Zone revisited written by Paul Kibler Sime and published by . This book was released on 1993 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Great Lakes tectonic zone (GLTZ) is a Late Archean crustal boundary (paleosuture) at least 1,200 kilometers long that juxtaposes a Late Archean greenstone-granite terrane (Wawa subprovince of Superior province) on the north and an Early to Late Archean gneiss terrane (Minnesota River Valley subprovince) on the south. Recent mapping of an exposed seg- ment in the Marquette, Michigan, area provides new data on the vergence of the structure. These data necessitate reexami- nation of the COCORP seismic-reflection profiling in central Minnesota, which has been the principal basis for past views on the vergence of the GLTZ. In the Marquette area, the GLTZ is a northwest-striking mylonite zone about 2.3 kilometers wide that is superposed on previously deformed rocks of both Archean terranes. Shear zone walls strike N. 55°-60° W., and foliation in mylonite within the GLTZ strikes (average) N. 70° W. and dips 75° SW. A stretching lineation plunges 42° in a S. 43° E. direction. Hinges of tight to open (sheath?) folds of both Z- and S-symmetries plunge parallel to the lineation. The attitude of the lineation (line of tectonic transport and X finite strain axis), together with asymmetric kinematic indicators, indicates that collision at this locality was oblique; the collision resulted in dextral- thrust shear along the boundary, northwestward vergence, and overriding of the greenstone-granite terrane by the gneiss terrane. In contrast, the seismic-reflection profiling in central Minnesota has been interpreted by several investigators to indicate that the GLTZ is a shallowly north dipping (=30°) structure, which implies southward vergence on a north-dipping subduction zone. We suggest, alternatively, that the shallow- dipping reflectors in the seismic profiles indicate lithologic contacts related to recumbent and gently inclined folds (D1), perhaps enhanced by ductile deformation zones, and that the Morris fault is indeed the GLTZ. The Morris fault strikes about N. 70° E., dips steeply southeastward, is transparent in seismic profiles, appears to be narrow, and coincides with the inferred position of the GLTZ as shown on earlier maps. The oblique collision along northwest-trending segments of the GLTZ would be expected to produce dextral transpression across a large region north of the GLTZ, and may have produced an early nappe-forming event (D1) as well as younger upright folds (D2), and as a later, more brittle event, the numerous dextral faults and conjugate sinistral faults that are widespread in the Wawa and adjacent subprovinces.

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1990-07 with total page 1288 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Bulletin written by Paul Kibler Sims and published by . This book was released on 1983 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Early Proterozoic Michigamme Formation of northern Michigan was deposited in the southeastern part of the Animikie basin. The formation conformably overlies the Goodrich Quartzite and comprises three widespread members a lower member of thin-bedded shale, siltstone, and sandstone; the Bijiki Iron-formation Member; and an upper member of tur- biditic graywacke, siltstone, and mudstone and a few local members. The Goodrich Quartzite is interpreted as having been deposited in a tidally influenced shallow marine environ- ment. The lower member of the Michigamme is interpreted as having been deposited in a tidally influenced environment, the iron-formation member as having been deposited below wave base in somewhat deeper water, and the upper member as having been deposited in still deeper water with turbidity currents being a major depositional mechanism. Several lines of evidence including paleocurrents, paleo- geographic setting, and neodymium isotopes suggest that the graywacke of the southern part of the outcrop area was derived from the south (Early Proterozoic Wisconsin magmatic terranes, Archean miniplates, and older Early Proterozoic sedimentary units formed on the continental margin), and that the graywacke in the northern area was derived from an Archean terrane to the north. The tectonic model that best fits the available data is a northward-migrating foreland basin.

Download or read book Publications of the Geological Survey written by and published by . This book was released on 1971 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mineral Frontiers on Indian Lands written by and published by . This book was released on with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on with total page 1240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Precambrian Conterminous U S written by John C. Reed, Jr. and published by Geological Society of America. This book was released on 1993 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt: This wide-ranging discussion of Precambrian rocks includes contributions from a diverse array of authors actively engaged in investigations of various aspects of U.S. Precambrian geology. Summary discussions by the editors of the five major chapters place these contributions in a logical regional framework.

Download or read book Minnesota s Geology written by Richard W. Ojakangas and published by U of Minnesota Press. This book was released on 1982 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Have you ever wondered how the Mississippi River was formed? Or why shark teeth have been found in the Iron Range of the Upper Midwest? Towering mountain ranges, explosive volcanoes, expansive glaciers, and long-extinct forms of both land and sea life were an important part of Minnesota's ancient history. Today the evidence of this remarkable heritage is revealed in the state's rocky outcroppings, stony soils, and thousands of lakes.

Download or read book Voyageurs National Park N P Wilderness Recommendation written by and published by . This book was released on 1992 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Voyageurs National Park Minnesota written by Voyageurs National Park (Minn.) and published by . This book was released on 1991 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings and Abstracts for the Annual Institute on Lake Superior Geology written by Institute on Lake Superior Geology. Meeting and published by . This book was released on 2010 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Publications of the U S Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 1990 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Archean to Anthropocene written by James D. Miller and published by Geological Society of America. This book was released on 2011-01-01 with total page 593 pages. Available in PDF, EPUB and Kindle. Book excerpt: