Subsurface densities and lithospheric flexure of the Himalayan foreland in Pakistan

1989 ◽  
pp. 217-236 ◽  
Author(s):  
Yannick Duroy ◽  
Abul Farah ◽  
Robert J. Lillie
Keyword(s):  
Lithospheric Flexure

scholarly journals A Global Survey of Lithospheric Flexure at Steep-Sided Domical Volcanoes on Venus Reveals Intermediate Elastic Thicknesses

2020 ◽  
Author(s):  
Madison E Borrelli ◽  
Joseph Ghilarducci O'Rourke ◽  
Suzanne E Smrekar ◽  
Colby M Ostberg
Keyword(s):  
Global Survey ◽  
Lithospheric Flexure

GPU-based pseudo-transient finite difference solution for power-law viscous flow in cartesian, polar and spherical coordinates

2021 ◽  
Author(s):  
Emilie Macherel ◽  
Yuri Podladchikov ◽  
Ludovic Räss ◽  
Stefan M. Schmalholz
Keyword(s):  
High Resolution ◽  
Finite Difference ◽  
Viscous Flow ◽  
Power Law ◽  
High Performance ◽  
Viscoelastic Behavior ◽  
Iterative Solution ◽  
Circular Inclusion ◽  
Lithospheric Flexure ◽  
Gpu Architectures

<p>Power-law viscous flow describes well the first-order features of long-term lithosphere deformation. Due to the ellipticity of the Earth, the lithosphere is mechanically analogous to a shell, characterized by a double curvature. The mechanical characteristics of a shell are fundamentally different to the characteristics of plates, having no curvature in their undeformed state. The systematic quantification of the magnitude and the spatiotemporal distribution of strain, strain-rate and stress inside a deforming lithospheric shell is thus of major importance: stress is for example a key physical quantity that controls geodynamic processes such as metamorphic reactions, decompression melting, lithospheric flexure, subduction initiation or earthquakes.</p><p>Stress calculations in a geometrically and mechanically heterogeneous 3-D lithospheric shell require high-resolution and high-performance computing. The pseudo-transient finite difference (PTFD) method recently enabled efficient simulations of high-resolution 3-D deformation processes, implementing an iterative implicit solution strategy of the governing equations for power-law viscous flow. Main challenges for the PTFD method is to guarantee convergence, minimize the required iteration count and speed-up the iterations.</p><p>Here, we present PTFD simulations for simple mechanically heterogeneous (weak circular inclusion) incompressible 2-D power-law viscous flow in cartesian and cylindrical coordinates. The flow laws employ a pseudo-viscoelastic behavior to optimize the iterative solution by exploiting the fundamental characteristics of viscoelastic wave propagation.</p><p>The developed PTFD algorithm executes in parallel on CPUs and GPUs. The development was done in Matlab (mathworks.com), then translated into the Julia language (julialang.org), and finally made compatible for parallel GPU architectures using the ParallelStencil.jl package (https://github.com/omlins/ParallelStencil.jl). We may unveil preliminary results for 3-D spherical configurations including gravity-controlled lithospheric stress distributions around continental plateaus.</p>

MARGIN-SCALE, BASEMENT-INVOLVED COMPARTMENTALISATION OF AUSTRALIA'S NORTH WEST SHELF: A PRIMARY CONTROL ON BASIN-SCALE RIFT, DEPOSITION AL AND REACTIVATION HISTORIES

1999 ◽  
Vol 39 (1) ◽  
pp. 40 ◽  
Author(s):  
G.W. O'Brien ◽  
M. Morse ◽  
D. Wilson ◽  
P. Quaife ◽  
J. Colwell ◽  
...  
Keyword(s):  
Transition Zone ◽  
Fault Reactivation ◽  
Small Displacement ◽  
Driving Mechanism ◽  
Fracture System ◽  
Primary Control ◽  
North West ◽  
Seal Failure ◽  
Lithospheric Flexure ◽  
Basin Scale

Australia's North West Shelf is segmented into four discrete margin-scale compartments which have distinct rift and reactivation histories. Two of the margin segments, the Carnarvon and Bonaparte compartments, are very wide (500–600 km), marginal plateau systems, whereas the other two segments, the Canning and Browse compartments, are narrower and steeper. The boundaries between individual rift compartments appear to be controlled by Proterozoic fracture systems.The Browse-Bonaparte transition zone is a major, northwest-trending Proterozoic fracture system which has a series of igneous intrusions along its length. These intrusions are located where the fracture system is cut by younger, northeast-trending extensional faults. This transition zone is a margin-scale fault relay zone, with intense fault overlap along the transition resulting in the zone being a long-lived, syn-rift high. Moreover, the transition zones between adjacent wide and narrow margins are prime locations for the entry point of siliciclastics into the rift or post-rift margin system. As a result, well-developed channel systems often cut through these boundaries and high quality reservoirs (particularly low-stand fans) are developed.Neogene fault reactivation, associated with convergence of the Australasian and Eurasian plates, is evident along the North West Shelf. The style of this reactivation is, however, closely controlled by the margin- scale architecture. In the Browse and Carnarvon basins, Neogene inversion is common, but at the leading edge of the collisional system, the Bonaparte compartment, the fault style is exclusively extensional. It appears that lithospheric flexure, associated with localised foreland development (i.e. the Timor Trough), has been the driving mechanism for the extensional faulting within the Bonaparte compartment. Crustal convergence seems to have been accommodated completely by thrusting on the northwestern margin of Timor and by foreland formation. In contrast, the Browse and Carnarvon compartments lacked a 'buffering' foreland system and, being adjacent to rigid and thin oceanic crust which transmits stress well over long distances, the inversional stresses were transmitted directly into these compartments.As a result of these margin-scale processes, the Bonaparte compartment is characterised by a thin regional seal (often 100 ms) on Neogene extensional faults—a combination which strongly favours fault seal failure and trap breach. In contrast, the Browse compartment is characterised by thick seals and small displacement Neogene faults, and thus the probability of fault seal failure is much less.

Sign in / Sign up

Export Citation Format

Share Document