Mechanics of gravitational spreading of steep-sided ridges (Sackung)

Mechanics of gravitational spreading of steep-sided ridges (Sackung)

GEOMECHANICS ABSTRACTS 881004 Rheoiogy of the lithosphere: selected topics Kirby, S H, Kronenberg, A K General Reo Geophys V25. N6. July 1987, P121...

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GEOMECHANICS ABSTRACTS

881004 Rheoiogy of the lithosphere: selected topics Kirby, S H, Kronenberg, A K

General

Reo Geophys V25. N6. July 1987, P1219.1244

881001 1984 Rock Mechanics Theses Alntratqs ISRM

Recent work concerning theology of the hthosphere is rewewed Particular attention is [oven to the followmg topics flexure of the oceanic hthosphere, deformation of the continental lithosphere, rheologtcai stratification of the continental lithosphere, strain softenmg and strain Ioeahsatlon in shear zones, and seismic amsotropy and flow in the lithosphere Finally, a guide to recent rock mechanics literature is presented 713 refs

Lisbon ISRM. Aug 1987 Contains details of 23 theses in the field of rock mechanics, submitted in 1984 to umversmes from around the world Author, title, educational establishment, availability, and price are listed, where known Abstracts in english, together with some in German and/or French, are presented in many cases

8810O5 Role of pore fluids in tectonic processes Mase, C W, Smith, L

Rev Geopkys V25, N6, July 1987, P!348-1358 Mechanically free pore water is present in many upper crustal rocks Fired flow in the porous medium dunng deformation and the effects of local heating on the fluid and stress field are important when consldenng the mechanical response of rocks Recent work which includes the role of pore fluids in system dynamics is reviewed, with parucular reference to the followmg topics hydraulic properties of crustal rocks, effects of fluid flow on the thermal regime of the upper crust, and the role of pore fluids in tectomc deformation, mcludmg earthquake processes, the mechanics of thrust belts, and evolution of sedimentary basins 181 refs

Geology Tectonic processes and structural geology 881002 Assessing the relative importance of compaction processes and cementation to reduction of porosity in sandstones Houseknecht, D W

Bull Am Assoc Engng Geol V71, N6, June 1987. P633-642 881006 Sandbox model studies of inversion tectonics Koopman, A, Speksmjder, A, Horsefield, W T

A well sorted sand has a porosity around 40% at the depositlonal surface, but this is reduced by mechanical compaction, intergranular pressure solution and cementation dunng burial dlagenesls The first two mechanisms irreversibly reduce intergranular volume, the last occludes but does not reduce it A technique by which the relative importance of these processes can be quantified is presented and illustrated with data from petroleum reservoir sandstones

Teetonophysics V137, NI/4, 1 June 1987, P379-388 Scaled plane strain sandbox models have been used to simulate basement controlled inversion in a sedimentary overburden and study the dynamic and kinematic processes Two basement configurations were used Experiments show structural inversion reactivates pre-existing faults and generates new faults in the overburden Inversion related faults are the result of horizontal compression associated with one of the fault blocks or with verucal uplift of basement blocks

881003 Meclumies of gravitational spreading of steep.sided ridges (Sackung) Savage, W Z, Varnes, D J

881007 Finite-element analysis of an overturned fold using a viscousfluid model Labao Lan, Ren Wang

Int Assoc Engng Geoi Bull N35, Aprd 1987, P31-36

Tectonophystcs V139. N3/4, 1 Aug 1987. P309-314

Large scale spreading (sackung) of steep sided ndges is widely known and charactensed by linear fissures, trenches, and uphill facing scarps high on the sides, It is analysed as being due to the time dependent flow of the rock mass under gravitatlonal stress Using a pre~nously developed exact elastic solution, the stresses are calculated and used with the Coulomb criterion to determine the extent of failure under self weight When failure regions are estabhshed, a plastic flow solution is applied to describe the features common in sackung

The formauon of a natural overturned fold is simulated by finite element modelhng of a stogie viscous layer in a less viscous medium The constituent substances are taken to be Isotropic and mcompresslble and to behave as Newtoman flmds The deformation of the Huang-yuan fault in China was simulated by first compressmg the layers to form a symmetric fold and then sheanng along the upper surface Field data and modelled results compare well, suggesting this may be the relevant fold mechanism

© 1988 Pergamon Press pie Reproduction not permitted IA