Basement Tectonics 12 Central North America and Other Regions

The Proceedings of the Twelfth International Basement Tectonics Conference continues an emphasis on tectonic problems of the older continental crust. While the evolution of the southern margin of the North American plate receives needed attention, problem areas of the Appalachians and of the Italian region are also treated. Finally methods of geophysical probing of upper crustal structure are explored. Geoscientists from seven different countries present the results of their research. Full papers in this book target the Llano region of Texas, the Southern Oklahoma Aulacogen, the northern Reading Prong of the northeastern USA, the Sardinian-Corsican Massif, the El-Eredyia area of Egypt, and seismic imaging beneath thrust blocks. The shape of plutons is analyzed with respect to crustal magma traps and magma driving pressure for a specific site in an extensional setting. Shorter communications include studies on fracture development, both laboratory studies and field studies, propagation and reactivation of faults, and lithological and geochemical studies of basement terranes.

I Selected Articles.- Petrologic constraints on the tectonic evolution of the Llano uplift.- Geologic provinces of Oklahoma.- The Southern Oklahoma Aulacogen: a Cambrian analog for Mid-Proterozoic AMCG (Anorthosite-Mangerite-Charnockite-Granite) complexes?.- Surface and near-surface investigation of the alteration of the Mount Scott Granite and geometry of the Sandy Creek Gabbro pluton, Hale Spring area, Wichita Mountains, Oklahoma.- Multiple reactivations of rigid basement block margins: examples in the northern Reading Prong, U.S.A..- The Variscan geodynamic cycle in the Sardinian-Corsican Massif, according to the most recent data.- Geological and geophysical exploration for uranium mineralization in the El-Eredyia prospect area, Central Eastern Desert, Egypt.- Seismic imaging beneath thrust blocks.- II Abstracts.- Petrology and tectonic significance of the Polly Wright Cove pluton, Blue Ridge Province, Virginia: an extension-related, multiply-intrusive magmatic system of anorogenic origin.- Basement-involved and detached phases of deformation in the evolution of fold-thrust belts: examples from the southern Cordilheira do Espinhaço and the Paramirim deformation corridor, Brazil.- Evolution of the Late Proterozoic basement in the northern Appalachian orogenic system and implications for the Ouachita system.- The north-trending swarm of Mesozoic dikes in the southern Appalachians: its map pattern and significance for Mesozoic extension.- Crustal tectonic controlling metallogenies from Paleozoic to Tertiary in the North Patagonian region, Argentina.- Early Proterozoic ductile reworking of Archean basement in the central Laramie range: a complex response to the Cheyenne belt, trans-Hudson and central plains orogens.- Propagation of high angle, dip-slip basement faultzones into overlying sedimentary rocks.- Geologic provinces of Oklahoma.- Evidence from the stratigraphic record for basement deformation in southeastern Nebraska, midcontinent U.S.A..- Petrologic constraints on the tectonic evolution of the Llano uplift.- Proterozoic evolution of the Llano uplift, central Texas: evidence for high-pressure metamorphism from the Oxford mafic body.- Dikes in the Precambrian of the eastern Arbuckle mountains.- Neoproterozoic continental-scale transpression megazone in eastern Brazil.- Multiple reactivations of major fault zones in the northern Reading prong, U.S.A..- Structural evolution of Cima termine area, Val Venosta (northern Italy).- On fracture development in rock subjected to compression.- The characteristics and tectonic evolution of the basement of the collision orogenic belt on the southeastern margin of the Yangtze plate.- Revised granite-gabbro age relationships, southern Oklahoma aulacogen, U.S.A..- Late Precambrian strike-slip fault system of the Wichita-Amarillo mountains as delineated by detailed aeromagnetic data.- Crustal growth during continental rifting: an example from the southern Oklahoma aulacogen.- Integrated petrologic and sedimentologic studies of a late Neoproterozoic rift basin within the Grenvillian basement of Virginia.- Structural imprint of the Wichita mountains frontal zone on overlying sediments.- Plastic deformation as a factor of material transformation of rocks (southern Tien Shan).- Evolution of Proterozoic granitoids, eastern Arbuckle mountains, Oklahoma.- Seismic imaging beneath thrust blocks.- Seismicity and tectonic relationships of north central Oklahoma.- Distribution of Phanerozoic faulting and folding, seismicity, and ore deposits in the midcontent region, U.S.A.: a reflection widespread Proterozoic rifting in the North American craton?.- The Variscan geodynamic cycle in the Sardinian-Corsican massif.- The influence of structural position and lithology on the fracture distribution in the east Kaibab monocline southeastern Utah: implications for fluid flow properties.- Evolution of Grenville tectonic provinces, southeastern Llano uplift, central Texas.- Anatomy of the Grenville orogen in west Texas.- Halokinetic associated crustal stretching in the southern Red Sea: new observations of the basement and sedimentary cover from refraction constrained reflection seismic stratigraphy.- Partial melting of Mount Scott granite at 850°C and 500 bars.- Investigation of the Mount Scott granite drill core, Wichita mountains, Oklahoma.- Geological and geophysical exploration for uranium mineralization on Ei-Erediya prospect area, central eastern desert, Egypt.- Nature and age of ductile deformation associated with the “anorogenic” Town Mountain granite, Llano uplift, central Texas.- Interdependency of mechanical and chemical processes during the evolution of chloritic breccia, Sacramento mountains, southeastern California.- Factors affecting limiting angles for fault reactivation in basement rocks.- Lead isotope mapping of crustal reservoirs within the Grenville superterrane: central and southern Appalachians.- Petrology and geochemistry of a late proterozoic anorgenic supersuite, Laurentian Appalachians, Virginia and North Carolina: implications for magma-generation associated with cratonic extension.- The role of recurrent tectonics in the formation of the Nemaha uplift and Cherokee-Forest City basins and adjacent structural features in eastern Kansas and contiguous states, U.S.A..- COCORP southwestern Oklahoma siesmic lines revisited.