Passive roof thrusting and forelandward fold propagation in scaled brittle-ductile physical models of thrust wedges (Articolo in rivista)

Type
Label
  • Passive roof thrusting and forelandward fold propagation in scaled brittle-ductile physical models of thrust wedges (Articolo in rivista) (literal)
Anno
  • 2001-01-01T00:00:00+01:00 (literal)
Alternative label
  • BONINI M. (2001)
    Passive roof thrusting and forelandward fold propagation in scaled brittle-ductile physical models of thrust wedges
    in Journal of geophysical research
    (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori
  • BONINI M. (literal)
Pagina inizio
  • 2291 (literal)
Pagina fine
  • 2311 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#altreInformazioni
  • This paper provides new insights into the development of fold-and-thrust belts in relation to the presence of décollement layers. Journal of Geophysical Research is considered one of the best journals in the Earth Science field and presents only high quality articles about geophysics and quantitative analysis of tectonic processes. (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume
  • 106 (literal)
Rivista
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#note
  • Impact factor: 2,609 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#descrizioneSinteticaDelProdotto
  • This article illustrates the results of an analogue modelling investigation focusing on the role of a décollement layer in the structural style of fold-and-thrust belts. Experimental results indicate that roof-sequences exhibit two distinct styles of deformation: (a) passive-roof duplex geometry (PRD) and (b) outward propagation of folding along the décollement (OFP). In PRD geometry, the roof-sequence remain relatively “stationary” being underthrust by a wedge-shaped floor-duplex, while in OFP, displacement along the floor thrusts is transferred horizontally along the décollement layer. Experiments suggest the occurrence of a genetic relationship between shear stresses and the development of PRD or OFP geometry. The transition field between OFP and PRD styles has been approximated by curvilinear regression of transition-style experimental data points. Experiments simulate many of the salient characteristics of fold-and-thrust belts developed above a basal evaporite décollement, as well as the development of passive-roof duplexes at mountain fronts. From a quantitative point of view, shear stress values inferred for many fold-and-thrust belts correlate well the deformation fields predicted by the present experimental study. This allows to propose a simple model describing the mechanical behaviour of natural roof-sequences underlain by a décollement layer. (literal)
Note
  • Scopus (literal)
  • Google Scholar (literal)
  • ISI Web of Science (WOS) (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni
  • IGG- Istituto di Geoscienze e e Georisorse (literal)
Titolo
  • Passive roof thrusting and forelandward fold propagation in scaled brittle-ductile physical models of thrust wedges (literal)
Abstract
  • A set of scaled analogue models was performed to investigate the role of a décollement layer in the structural style of fold-and-thrust belts. Silicone putty (SGM 36) has been employed to represent the ductile décollement, while frictional material (quartz-sand) has been used to simulate the brittle behaviour of roof- and floor- sequences, situated above and below the décollement respectively. In order to explore a wide combination of strength profiles, models have been deformed under five distinct rates of compression (0.15, 0.3, 0.45, 0.6 and 1.5 cm h-1) employing four different thicknesses for the silicone layer (0.1, 0.2, 0.4 and 0.8 cm). Experimental results indicate that roof-sequences exhibit two distinct styles of deformation: (a) passive-roof duplex geometry (e.g. Banks and Warburton, 1986; PRD) and (b) outward propagation of folding along the décollement (e.g. Davis and Engelder, 1985; OFP). In PRD geometry, the roof-sequence remain relatively “stationary” being underthrust by a wedge-shaped floor-duplex, while in OFP, displacement along the floor thrusts is transferred horizontally along the décollement layer. Experiments suggest the occurrence of a genetic relationship between shear stresses (at the base of the floor-sequence, tb, and within the ductile layer, td) and the development of PRD or OFP geometry. For a given strain-rate deformation pattern of roof-sequences depends upon the tb/td, ratio as well as the absolute tb and td values. The transition field between OFP and PRD styles has been approximated by curvilinear regression of transition-style experimental data points, with a minimum value of tb, varying between about 112 and 160 Pa, to enter the PRD field. Syntectonic sedimentation in the molasse basin is found to inhibit development of folding into the foreland, but to promote PRD style. Experiments simulate many of the salient characteristics of fold-and-thrust belts developed above a weak basal evaporite décollement, as well as the development of passive-roof duplexes at mountain fronts. Shear stress values inferred for many fold-and-thrust belts correlate well the deformation fields predicted by the present experimental study, allowing to propose a simple model describing the mechanical behaviour of natural roof-sequences underlain by a décollement layer. (literal)
Prodotto di
Autore CNR
Insieme di parole chiave

Incoming links:


Autore CNR di
Prodotto
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#rivistaDi
Insieme di parole chiave di
data.CNR.it