The Bali-Flores Basin: geological transition from extensional to subsequent compressional deformation

2018 ◽  
Author(s):  
H. Prasetyo
Keyword(s):  
Compressional Deformation

Parentage of Archean basement within a Paleoproterozoic orogen and implications for on-craton diamond preservation: Slave craton and Wopmay orogen, northwest Canada

2017 ◽  
Vol 54 (2) ◽  
pp. 203-232 ◽  
Author(s):  
Luke Ootes ◽  
Valerie A. Jackson ◽  
William J. Davis ◽  
Venessa Bennett ◽  
Leanne Smar ◽  
...  
Keyword(s):  
Detrital Zircon ◽  
Crystalline Basement ◽  
Stability Field ◽  
Isotopic Data ◽  
The West ◽  
Slave Craton ◽  
Reasonable Explanation ◽  
Compressional Deformation ◽  
Archean Basement

The Wopmay orogen is a Paleoproterozoic accretionary belt preserved to the west of the Archean Slave craton, northwest Canada. Reworked Archean crystalline basement occurs in the orogen, and new bedrock mapping, U–Pb geochronology, and Sm–Nd isotopic data further substantiate a Slave craton parentage for this basement. Detrital zircon results from unconformably overlying Paleoproterozoic supracrustal rocks also support a Slave craton provenance. Rifting of the Slave margin began at ca. 2.02 Ga with a second rift phase constrained between ca. 1.92 and 1.89 Ga, resulting in thermal weakening of the Archean basement and allowing subsequent penetrative deformation during the Calderian orogeny (ca. 1.88–1.85 Ga). The boundary between the western Slave craton and the reworked Archean basement in the southern Wopmay orogen is interpreted as the rifted cratonic margin, which later acted as a rigid backstop during compressional deformation. Age-isotopic characteristics of plutonic phases track the extent and evolution of these processes that left penetratively deformed Archean basement, Paleoproterozoic cover, and plutons in the west, and “rigid” Archean Slave craton to the east. Diamond-bearing kimberlite occurs across the central and eastern parts of the Slave craton, but kimberlite (diamond bearing or not) has not been documented west of ∼114°W. It is proposed that while the crust of the western Slave craton escaped thermal weakening, the mantle did not and was moved out of the diamond stability field. The Paleoproterozoic extension–convergence cycle preserved in the Wopmay orogen provides a reasonable explanation as to why the western Slave craton appears to be diamond sterile.

Magnetorheological behaviour of magnetic carrageenan gels against shear and compression strains

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Keisuke Negami ◽  
Tetsu Mitsumata
Keyword(s):  
Magnetic Field ◽  
Shear Strain ◽  
Field Effect ◽  
Vibration Suppression ◽  
Magnetic Field Effect ◽  
The Other ◽  
Iron Particles ◽  
Compressional Deformation ◽  
Compressional Strain ◽  
The Magnetic Field

AbstractMagnetic field effect on the elasticity was investigated for magnetic carrageenan gel when a shear and compressional deformation was applied to the gel. The magnetic carrageenan gel consists of carrageenan of a polysaccharide, and carbonyl iron particles. The dynamic viscoelastic measurement with shear strain revealed that the storage shear modulus of the gel increased from 1.0×104 to 2.3×106 Pa by applying a magnetic field of 320 mT. On the other hand, the compression measurement showed that the Young’s modulus increased from 6.2×104 to 5.9×105 Pa. The relative changes in the modulus with respect to the original modulus were 230 for shear strain and 9.5 for compressional strain, respectively. This strongly indicates that the magnetic field effect on viscoelasticity strongly depends on the geometry of directions of magnetic field and strain. The effect of vibration suppression of the present gel tuned by magnetic field is also presented.

scholarly journals Coeval compressional deformation and volcanism in the central Andes, case studies from northern Chile (23°S-24°S)

Tectonics ◽  
2009 ◽  
Vol 28 (6) ◽  
pp. n/a-n/a ◽  
Author(s):  
Gabriel González ◽  
José Cembrano ◽  
Felipe Aron ◽  
Eugenio E. Veloso ◽  
J. Bruce H. Shyu
Keyword(s):  
Case Studies ◽  
Central Andes ◽  
Northern Chile ◽  
Compressional Deformation

Dynamics of intra-plate compressional deformation: the Alpine foreland and other examples

1995 ◽  
Vol 252 (1-4) ◽  
pp. 7-59 ◽  
Author(s):  
Peter A. Ziegler ◽  
Sierd Cloetingh ◽  
Jan-Diederik van Wees
Keyword(s):  
Alpine Foreland ◽  
Compressional Deformation

Problems interpreting deep crustal reflectors beneath the Moine thrust between Shetland and the Scottish Highlands

1995 ◽  
Vol 132 (5) ◽  
pp. 465-472
Author(s):  
J. H. McBride ◽  
R. W. England
Keyword(s):  
Crustal Structure ◽  
Seismic Reflection ◽  
Normal Fault ◽  
Moho Discontinuity ◽  
The West ◽  
Scottish Highlands ◽  
Thrust Zone ◽  
Compressional Deformation ◽  
Seismic Reflection Profiles ◽  
Eastern Edge

AbstractOffshore seismic reflection profiles crossing the Caledonian orogenic front (locally, ?Moine thrust) between Shetland and the Scottish Highlands show a singular coherent east-dipping reflection underlain by a highly reflective dipping zone in the middle crust extending down to the Moho discontinuity. This reflector pattern varies spatially with respect to the eastern edge of the Precambrian Lewisian foreland as well as to previously mapped locations of the Moine thrust. Southwest of Shetland, the reflector pattern coincides with the offshore projection of the Moine thrust, but further south, toward the Highlands, the reflector diverges to the west of the thrust and actually underlies autochthonous Lewisian foreland basement. Where this reflector pattern diverges from the Moine thrust, two interpretations are possible: the prominent reflector is part of a basement imbricate thrust duplex within the footwall (or ‘lower plate’) of the Moine thrust that merges with the thrust zone further north and/or it was originally a Proterozoic normal fault which, further north around Shetland, was reactivated or over-printed by the Moine thrust. The latter interpretation supports the importance of pre-existing crustal structure in controlling Caledonian compressional deformation.

Sign in / Sign up

Export Citation Format

Share Document