An unstable kinematic state of the Himalayan tectonic wedge: Evidence from experimental thrust-spacing patterns

Bose, Santanu; Mandal, Nibir; Mukhopadhyay, Dilip K.; Mishra, P. K.

doi:10.1016/j.jsg.2008.10.002

Cited by 35 publications

(44 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We adopted the conventional method of sandbox experiments (Mulugeta, 1988;Mulugeta andKoyi, 1987, 1992;Huiqi et al 1992;Marshak and Wilkerson, 1992;Mandal et al 1997;Bose et al 2009). Dry non-cohesive natural sand (Coulomb material) with an average grain size of less than 500 mm, bulk density r = 1.6 gm/cm 3 and internal co-efficient of friction, µ = 0.57 (Hubbert, 1951;Davis et al 1983) was used as an experimental material.…”

Section: Experimental Methodsmentioning

confidence: 99%

“…Loose sand materials provide a better approximation for scaled model experiments for large-scale brittle deformations in the uppermost crust (Davis et al 1983;Mulugeta, 1988;Liu et al 1992;Mandal et al 1997). Models were prepared by sieving alternate layers of sand of contrasting colours as used by the earlier workers (Davis et al 1983;Mulugeta, 1988;Liu et al 1992;Mandal et al 1997;Marques and Cobbold, 2002;Lujan et al 2003;Koyi, 1995;Yamada et al 2006;Bose et al 2009). Sand masses were sieved on a horizontal rigid base to form a layered sand bed.…”

Section: Experimental Methodsmentioning

confidence: 99%

“…The erosion processes also control the progression of frontal thrusts. In case of non-erosional conditions, successive thrusts develop with a systematic spatial arrangement, which is a function of several factors, such as bed thickness, basal friction, basal slope, surface slope and topographic variation (Bombolakis, 1986;Panian and Pilant, 1990;Mandal et al 1997;Schott and Koyi, 2001;Mulugeta and Koyi, 1987;Bose et al 2009). Recent experimental studies show that the erosion processes perturb such sequential frontal thrust progression, and greatly modify the final thrust architecture (Konstantinovskaia and Malavieille, 2005).…”

mentioning

confidence: 99%

“…Earlier experiments showed that the spatial distribution of imbricate thrusts varies with basal friction (Bose et al 2009). Higher basal friction promotes continuous increase in spacing between the consecutive thrusts with wedge growth.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Interaction of surface erosion and sequential thrust progression: Implications on exhumation processes

Bose

Mandal²

2010

J Geol Soc India

Self Cite

View full text Add to dashboard Cite

This paper investigates the evolution of thrust wedges with concomitant surface erosion, and its bearing on the exhumation processes in orogenic belts. We performed sandbox experiments, simulating syn-orogenic erosion on forelandward sloping surfaces (~4 o ). Experiments show that the erosion process has a significant control on the progression of frontal thrusts. In case of no-erosion condition, wedges with high basal friction develop frontal thrusts with strongly increasing spacing. In contrast, for the same basal friction the thrusts show uniform spacing as the wedge development involves concomitant surface erosion. On the other hand, the erosion promotes reactivation of hinterland thrusts in wedges with low basal friction. We show that erosion-assisted thrust reactivation is the principal mechanism for exhumation of deeper level materials in orogens. Efficiency of this mechanism is largely controlled by basal friction. The exhumation of deeper level materials is limited, and occurs within a narrow, sub-vertical zone in the extreme hinterland when the basal friction is high (µ b = 0.46). In contrast, the process is quite effective in wedges with low basal friction (µ b =0.36), resulting in exhumation along gently dipping foreland-vergent thrusts as well as along thrusts, subsequently rotated into steep attitude. The zone of exhumation also shifts in the foreland direction in the course of horizontal movement. Consequently, deeper level materials cover a large area of the elevated part of the wedge.

show abstract

Section: Experimental Methodsmentioning

confidence: 99%

Section: Experimental Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Interaction of surface erosion and sequential thrust progression: Implications on exhumation processes

Bose

Mandal²

2010

J Geol Soc India

Self Cite

View full text Add to dashboard Cite

show abstract

“…Basal friction is directly proportional with critical taper of the wedge (Mulugeta, 1988). The larger is the basal friction, the more numerous are the thrusts in the wedge and the smaller is the thrust spacing (Bose et al, 2009). Most importantly basal friction controls fluid pressure in the wedge (Davis et al, 1983).…”

Section: Introductionmentioning

confidence: 99%

Estimating basal friction and fluid pressure from the geometry and spacing of frontal faults in Naga fold thrust belt, India

Ghosh

Hazra

2011

Marine and Petroleum Geology

View full text Add to dashboard Cite

Critical taper analysis reveals lithological control of variations in detachment strength: An analysis of the Alpine basal detachment (Swiss Alps)

Hagke

Oncken

Evseev

2014

Geochem Geophys Geosyst

View full text Add to dashboard Cite

[1] Although evidence for weak detachments underlying foreland thrust belts exists, very little is known about the lateral variations in effective strength, as well as the geological nature of such variations. Using critical taper analysis, we show that a detailed and systematic measurement of surface slope of the Central European Alps reveals variations in strength parameter F along the detachment, based on the argument that the Alps are close to the critical state. We show that the basal detachment is very weak near the deformation front but strengthens toward the hinterland. Very low F (effective coefficient of friction plus normalized cohesion) values of <0.1 and even 0.05 occur within evaporites and within shales in Triassic (west) or Upper Cretaceous/Lower Tertiary sequences (east) used by the Alpine sole detachment. These very low values in shales-comparably low values are reported from other orogens-are caused partly by slightly elevated pore pressures (k > 0.54) but may also require additional mechanisms of dynamic weakening.

show abstract

An unstable kinematic state of the Himalayan tectonic wedge: Evidence from experimental thrust-spacing patterns

Cited by 35 publications

References 38 publications

Interaction of surface erosion and sequential thrust progression: Implications on exhumation processes

Interaction of surface erosion and sequential thrust progression: Implications on exhumation processes

Estimating basal friction and fluid pressure from the geometry and spacing of frontal faults in Naga fold thrust belt, India

Critical taper analysis reveals lithological control of variations in detachment strength: An analysis of the Alpine basal detachment (Swiss Alps)

Contact Info

Product

Resources

About