Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Evolution of fracture networks in shear zones: In-sights from see-through experiments on biphenyl aggregates
Autore:
Streit, JE; Cox, SF;
Indirizzi:
Australian Natl Univ, Dept Geol, Res Sch Earth Sci, Canberra, ACT 0200, Australia Australian Natl Univ Canberra ACT Australia 0200 rra, ACT 0200, Australia
Titolo Testata:
JOURNAL OF STRUCTURAL GEOLOGY
fascicolo: 1, volume: 24, anno: 2002,
pagine: 107 - 122
SICI:
0191-8141(2002)24:1<107:EOFNIS>2.0.ZU;2-9
Fonte:
ISI
Lingua:
ENG
Soggetto:
DEEP FLUID CIRCULATION; FAULT ZONES; DYNAMIC RECRYSTALLIZATION; REGIONAL METAMORPHISM; VOLUME LOSS; DEFORMATION; QUARTZ; FLOW; MYLONITES; BRITTLE;
Keywords:
fracture networks; shear zones; biphenyl aggregates; see-through experiments;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
56
Recensione:
Indirizzi per estratti:
Indirizzo: Streit, JE Univ Adelaide, Nat Ctr Petr Geol & Geophys, Thebarton Campus, Adelaide, SA5005, Australia Univ Adelaide Thebarton Campus Adelaide SA Australia 5005 ralia
Citazione:
J.E. Streit e S.F. Cox, "Evolution of fracture networks in shear zones: In-sights from see-through experiments on biphenyl aggregates", J STRUC GEO, 24(1), 2002, pp. 107-122

Abstract

Evolution of fracture porosity in mid-crustal shear zones can be simulatedin in-situ experiments. Evolution of fracture networks was monitored during simple shearing of 2-mm-wide zones in wet and dry aggregates of polycrystalline, biphenyl (C6H5C6H5) in a Urai-Means see-through deformation apparatus. At low effective confining pressures in wet samples, mixed brittle-viscous deformation occurred at all strain rates (5.6 x 10(-4) - 5.8 x 10(-6) s(-1)) at 94-97% of the absolute melting temperature. At the fastest strain rate, progressive shearing is rapidly localized to produce a narrow fault zone along a shear zone boundary. In contrast, at the slowest strain rate, fractures develop throughout the shear zone and connect to form continuous fracture systems at low shear strains (gamma approximate to 2). These fracture systems accommodate most of the subsequent displacement in contrast to little fracturing and predominantly viscous deformation in a nominally dry experiment. Jogs, as parts of stairstepping fracture networks in wet samples, resemble in shape and distribution veins found in mid- to lower crustal shear zones. The experiments indicate that, from low strains onwards, the presence of fluids close to confining pressure in creeping shear zones can lead to the development of connected fracture networks that also localize most of the displacement. (C) 2001 Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 27/09/20 alle ore 22:53:07