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Page 4778, results 119426 - 119450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
The case for tectonic denudation by the Heart Mountain fault - A response
W. G. Pierce
1987, Geological Society of America Bulletin (99) 552-568
Two basic concepts pertaining to the history of the Heart Mountain fault of northwestern Wyoming have recently been challenged; one, that there was tectonic denudation, and two, that volcanic rock of the Wapiti Formation was deposited on the exposed fault surface. Tectonic denudation is believed to have occurred as a...
Methods and applications in surface depression analysis
Susan K. Jenson, Charles M. Trautwein
1987, Conference Paper, Auto-Carto VIII: Proceedings of the international symposium on computer-assisted cartography
Gridded surface data sets are often incorporated into digital data bases, but extracting information from the data sets requires specialized raster processing techniques different from those historically used on remotely sensed and thematic data. Frequently, the information desired of a gridded surface is directly related to the topologic peaks and...
Alleghanian deformation, metamorphism, and granite emplacement in the central Piedmont of the southern Appalachians
J. Wright Horton, Jr., J. F. Sutter, T. W. Stern, D.J. Milton
1987, American Journal of Science (287) 635-660
Evidence of late Paleozoic (Alleghanian) penetrative deformation, amphilbolite-facies, metamorphism, and syntectonic granite emplacement has been found in an area of the central Piedmont in the southern Appalachians. The High Shoals Granite batholith in the Kings Mountain belt of south-central North Carolina consists of coarse-grained, megacrystic biotite granite with a strong,...
Morphology and evolutionary significance of Adoneis pacifica gen. et sp. Nov. (Fragilariaceae, Bacillariophyta), a marine araphid diatom from Chile
George W. Andrews, Patricio Rivera
1987, Diatom Research (2) 1-14
A new marine diatom genus and species, Adoneis pacifica G.W. Andrews and P. Rivera, has been identified in Chilean coastal waters. This taxon shows obvious affinities to the genera Rhaphoneis and Delphineis, but cannot be classified in either, as they are currently construed. Adoneis pacifica resembles Rhaphoneis in outline and to some degree in the...
An algorithm for locating candidate labelling boxes within a polygon
Jan W. van Roessel
1987, Conference Paper, Auto-Carto VIII: Proceedings of the international symposium on computer-assisted cartography
Vector-based geographic information systems usually require annotation, such as a polygon number or attribute data, in a suitable location within a polygon. Traditional methods usually compute the polygon centroid, test the centroid for inclusion or exclusion, and select some alternative point when the centroid falls outside the polygon. Two problems...
Late Quaternary caldera-forming eruptions in the eastern Aleutian arc, Alaska
T. P. Miller, R.L. Smith
1987, Geology (15) 434-438
Late Quaternary calderas have been identified at 12 of 40 volcanic centers in the eastern Aleutian arc, and sufficient radiocarbon dates and geologic information have now been obtained to either date or constrain the timing of the climactic caldera-forming eruptions. At least eight major caldera-forming events, each characterized by estimated...
In search of the Abrams post office, Trinity County
Marvin A. Lanphere, William P. Irwin
1987, California Geology (40) 99-103
An understanding of earth history depends in part on stratigraphy, a division of geology in which the distinctive features of natural units or formations of layered rocks are studied and described and names are assigned to them. The procedures for describing and naming rock units in a uniform way are...
Correlation of early Cretaceous blueschists in Washington, Oregon and northern California
E. H. Brown, M.C. Blake Jr.
1987, Tectonics (6) 795-806
The protolith and metamorphic histories of Early Cretaceous blueschists that occur in Washington, Oregon, and California are remarkably similar. These blueschists are the Shuksan metamorphic suite of northwestern Washington, the Condrey Mountain schist of northern California and southern Oregon, and the Pickett Peak terrane of northern California and southwestern Oregon....
Remagnetization of the Coast Range Ophiolite and Lower Part of the Great Valley Sequence in Northern California and Southwest Oregon
L.S. Frei, M. Clark Blake Jr.
1987, Journal of Geophysical Research B: Solid Earth (92) 3487-3499
Overprinted magnetizations have been found at four localities in the Middle Jurassic Coast Range ophiolite and the overlying Upper Jurassic and Lower Cretaceous Great Valley sequence in northern California and at one locality in the partially correlative Lower Cretaceous Days Creek Formation in southwest Oregon. At Del Puerto Canyon, on...
Tectonostratigraphic terranes of the Croissilles Harbour region, South Island, New Zealand
C. A. Landis, M. Clark Blake Jr.
1987, Book chapter, Terrane accretion and orogenic belts
The boundary between Hokonui and Te Anau assemblages is flanked by a broad (10–20 km) zone of imbricated slabs of late Paleozoic and Mesozoic lithostratigraphic terranes. Five terranes are mapped, three of predominantly sedimentary character (Dun Mountain‐Maitai, Rai, Pelorus) are separated by two consisting of ophiolitic melange (Patuki, Croisilles). A...
Crustal extension along a rooted system of imbricate low-angle faults: Colorado River extensional corridor, California and Arizona
Keith A. Howard, B.E. John
1987, Geological Society Special Publication (28) 299-311
The upper 10 to 15 km of crystalline crust in the 100-km-wide Colorado River extensional corridor of mid-Tertiary age underwent extension along an imbricate system of gently dipping normal faults. Detachment faults cut gently down-section eastward in the direction of tectonic transport from a headwall breakaway, best expressed in the...
Thermal maturity of tectonostratigraphic terranes within the Franciscan Complex, California
M.B. Underwood, M. Clark Blake Jr., D. G. Howell
E.C. Leitch, Erwin Scheibner, editor(s)
1987, Book chapter, Terrane Accretion and Orogenic Belts
Indicators of organic metamorphism provide valuable tools for analyzing the thermal history of tectonostratigraphic terranes. Paleotemperature estimates derived from vitrinite reflectance, for example, are more precise than values based upon inorganic mineral assemblages in low‐grade rocks. Isothermal geometries must be interpreted within the context of structural...