Results 281 to 290 of about 24,733 (306)

Experimental Studies of Shear Deformation of Mantle Materials: Towards Structural Geology of the Mantle

Pure and Applied Geophysics, 1998
A brief outline is given on experimental studies carried out in the Minnesota Mineral and Rock Physics Laboratory of microstructural evolution and rheology of mantle mineral aggregates or their analogues, using a simple shear deformation geometry.
M. J. Daines, David L. Kohlstedt, Mark E. Zimmerman, Shuqing Zhang, Shun-ichiro Karato   +4 more
openaire   +2 more sources

Seismic soil classification of Italy based on surface geology and shear-wave velocity measurements

Soil Dynamics and Earthquake Engineering, 2019
Abstract During an earthquake the seismic wave amplification related to local site conditions can have a significant impact on the ground motion. In order to account for these local effects some proxies for the soil characteristics exist; e.g., the average shear-wave velocity of the upper 30 m ( V S , 30 ) , or the equivalent ...
Forte, Giovanni, Chioccarelli, Eugenio, De Falco, Melania, Cito, Pasquale, Santo, Antonio, Iervolino, Iunio   +5 more
openaire   +3 more sources

Geology and timing of dextral strike-slip shear zones in Danmarkshavn, North-East Greenland Caledonides [PDF]

Geological Magazine, 2006
The North-East Greenland eclogite province is divided into a western, central and eastern block by the sinistral Storstrømmen shear zone in the west and the dextral Germania Land deformation zone in the east. A family of steep, NNW-striking dextral mylonite zones in the Danmarkshavn area are geometrically and kinematically similar to the ductile ...
C. Sartini-Rideout, Jane A. Gilotti, William C. McClelland   +2 more
openaire   +1 more source

Geology and genesis of Nalunaq Palaeoproterozoic shear zone-hosted gold deposit, South Greenland

Applied Earth Science, 2000
AbstractThe Nalunaq deposit is a shear zone-hosted gold deposit characterized by very high grades (up to 5240 g Au/t over 0.8 m). The host rocks are Palaeoproterozoic metabasic rocks of the Nanortalik Nappe, which is part of the Ketilidian Mobile Belt. The Nanortalik Nappe consists of bedded massive pyrrhotite/graphitic chert horizons overlain by fine ...
L. Kludt, K. Kaltoft, D. M. Schlatter
openaire   +2 more sources

Shearing Phenomena at High Pressure of Possible Importance for Geology

The Journal of Geology, 1936
Various phenomena of plastic flow under shearing stress are studied at confining pressures up to $50,000 kg./cm.^2$ The shearing stress required to produce flow may-increase many fold beyond its normal value. There may be either "hardening" or "softening" phenomena while a steady state is being reached.
openaire   +2 more sources

Shear Wave Velocity- and Geology-Based Seismic Microzonation of Port-au-Prince, Haiti

Earthquake Spectra, 2011
A seismic site classification microzonation for the city of Port-au-Prince is presented herein. The microzonation is based on 35 shear wave velocity ( VS) profiles collected throughout the city and a new geologic map of the region. The VS profiles were obtained using the multichannel analysis of surface waves (MASW) method, while the geologic map was ...
Scott M. Olson, Ranon Dulberg, Clinton M. Wood, Russell A. Green, Albert R. Kottke, Jeff Bachhuber, Ellen M. Rathje, Brady R. Cox   +7 more
openaire   +2 more sources

Gently sloping shear zones in the Belomorian Mobile Belt: Geology, structure, and P–T parameters

Geotectonics, 2016
The Belomorian Mobile Belt (BMB) in northern Karelia mostly consists of gently sloping shear zones, whose gneisses and migmatized amphibolites and blastomylonites are typically thinly banded, with their banding consistently dipping north- and northeastward.
V. M. Kozlovskii, V. M. Savatenkov, A. V. Travin, A. V. Travin, E. B. Kurdyukov, L. B. Terent’eva, D. I. Korpechkov, V. V. Travin, V. V. Travin, M. N. Zaitseva   +9 more
openaire   +2 more sources

Higher Himalayan Shear Zone, Sutlej section: structural geology and extrusion mechanism by various combinations of simple shear, pure shear and channel flow in shifting modes

International Journal of Earth Sciences, 2009
The Higher Himalayan Shear Zone (HHSZ) in the Sutlej section reveals (1) top-to-SW ductile shearing, (2) top-to-NE ductile shearing in the upper- and the lower strands of the South Tibetan Detachment System (STDSU, STDSL), and (3) top-to-SW brittle shearing corroborated by trapezoid-shaped minerals in micro-scale. In the proposed extrusion model of the
MUKHERJEE, S, KOYI, HA
openaire   +3 more sources

Geology of the shear-hosted Brookbank gold prospect in the Beardmore–Geraldton belt, Wabigoon subprovince, Ontario

Canadian Journal of Earth Sciences, 2007
The Beardmore–Geraldton belt consists of steeply dipping, intercalated panels of metavolcanic and metasedimentary rocks along the southern margin of the granite–greenstone Wabigoon subprovince in the Archean Superior Province, Ontario. It is an important past-producing gold belt that includes classic epigenetic iron-formation-hosted deposits near ...
Greg M. Stott, Jerry C. DeWolfe, Bruno Lafrance   +2 more
openaire   +2 more sources

The 3D shear experiment over the Natih field in Oman. Reservoir geology, data acquisition and anisotropy analysis

Geophysical Prospecting, 1999
This paper describes a large‐scale reservoir characterization experiment carried out in Oman in 1991 which comprised the acquisition, processing and interpretation of a 28.4 km2 3D multicomponent seismic experiment over the Natih field. The objective of the survey was to obtain information on the fracture network present in the Natih carbonates from ...
null Potters, null Groenendaal, null Oates, null Hake, null Kalden   +4 more
openaire   +2 more sources