Sandstrom et al. (2020) present new elevation and age data for a flight of four marine terraces p... more Sandstrom et al. (2020) present new elevation and age data for a flight of four marine terraces preserved along the western limb of the Cape Range anticline in western Australia. Their interpretation of these data provides an alternative estimate for the amount of tectonic deformation that has occurred since terrace formation. They conclude that less tectonic uplift has occurred in the region than previously reported and posit that their study provides a template for reducing the uncertainty associated with last interglacial paleoshoreline reconstructions.
<p&amp... more <p>Coseismically displaced rock fragments (chips) in the near-field (less than 5 km) of the 2016 moment magnitude (M<sub>W</sub>) 6.1 Petermann earthquake (Australia) preserve directionality of strong ground motions. Displacement data from 1437 chips collected over an area of 100 km<sup>2 </sup>along and across the Petermann surface rupture is interpreted to record combinations of co-seismic directed permanent ground displacements associated with elastic rebound (fling) and transient  ground shaking, with intensities of motion increasing with proximity to the surface rupture. The observations provide a proxy test for available models for directionality of near-field reverse fault strong ground motions in the absence of instrumental data. This study provides a dense proxy record of strong ground motions at less than 5 km distance from a surface rupturing reverse earthquake, and may help test models of near-field dynamic and static pulse-like strong ground motion for dip-slip earthquakes.</p>
The 30th March 1986 Mw 5.7 Marryat Creek earthquake produced a highly arcuate 13 km long surface ... more The 30th March 1986 Mw 5.7 Marryat Creek earthquake produced a highly arcuate 13 km long surface rupture with maximum vertical displacement of 0.9 m. Sinistral displacement on the NE-SW limb, dextral displacement on the NNE-SSW limb, and maximum vertical displacement in the central apex of rupture supports SW over NE movement of a hanging-wall block. Epicentre locations are poorly constrained and inaccurate, locally exceeding distances of 30 km from the surface rupture. The most geologically and seismologically reasonable fault rupture model involves 3 bedrock-controlled faults. Assuming simple planar geometry, these would intersect 5.5 km SW of the rupture at 3 km depth, which is consistent with centroid depths of 3 – 4.5 km. Two trenches across the 1986 rupture trace show no preceding discrete offset since deposition of overlying sediments (100 – 130 ka). Strong evidence exists to suggest historic surface rupture was controlled by basement structures including a large pre-existing...
Abstract The inventory of over 200 fault scarps captured in GA's Australian neotectonics dat... more Abstract The inventory of over 200 fault scarps captured in GA's Australian neotectonics database, comprising both probable and proven palaeo-earthquake sources, has been used to produce preliminary estimates of the maximum credible magnitude earthquake ( ...
Sandstrom et al. (2020) present new elevation and age data for a flight of four marine terraces p... more Sandstrom et al. (2020) present new elevation and age data for a flight of four marine terraces preserved along the western limb of the Cape Range anticline in western Australia. Their interpretation of these data provides an alternative estimate for the amount of tectonic deformation that has occurred since terrace formation. They conclude that less tectonic uplift has occurred in the region than previously reported and posit that their study provides a template for reducing the uncertainty associated with last interglacial paleoshoreline reconstructions.
<p&amp... more <p>Coseismically displaced rock fragments (chips) in the near-field (less than 5 km) of the 2016 moment magnitude (M<sub>W</sub>) 6.1 Petermann earthquake (Australia) preserve directionality of strong ground motions. Displacement data from 1437 chips collected over an area of 100 km<sup>2 </sup>along and across the Petermann surface rupture is interpreted to record combinations of co-seismic directed permanent ground displacements associated with elastic rebound (fling) and transient  ground shaking, with intensities of motion increasing with proximity to the surface rupture. The observations provide a proxy test for available models for directionality of near-field reverse fault strong ground motions in the absence of instrumental data. This study provides a dense proxy record of strong ground motions at less than 5 km distance from a surface rupturing reverse earthquake, and may help test models of near-field dynamic and static pulse-like strong ground motion for dip-slip earthquakes.</p>
The 30th March 1986 Mw 5.7 Marryat Creek earthquake produced a highly arcuate 13 km long surface ... more The 30th March 1986 Mw 5.7 Marryat Creek earthquake produced a highly arcuate 13 km long surface rupture with maximum vertical displacement of 0.9 m. Sinistral displacement on the NE-SW limb, dextral displacement on the NNE-SSW limb, and maximum vertical displacement in the central apex of rupture supports SW over NE movement of a hanging-wall block. Epicentre locations are poorly constrained and inaccurate, locally exceeding distances of 30 km from the surface rupture. The most geologically and seismologically reasonable fault rupture model involves 3 bedrock-controlled faults. Assuming simple planar geometry, these would intersect 5.5 km SW of the rupture at 3 km depth, which is consistent with centroid depths of 3 – 4.5 km. Two trenches across the 1986 rupture trace show no preceding discrete offset since deposition of overlying sediments (100 – 130 ka). Strong evidence exists to suggest historic surface rupture was controlled by basement structures including a large pre-existing...
Abstract The inventory of over 200 fault scarps captured in GA's Australian neotectonics dat... more Abstract The inventory of over 200 fault scarps captured in GA's Australian neotectonics database, comprising both probable and proven palaeo-earthquake sources, has been used to produce preliminary estimates of the maximum credible magnitude earthquake ( ...
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