PALEOGENE STRIKE-SLIP DEFORMATION AND SEDIMENTATION ALONG THE SOUTHEASTERN MARGIN OF THE EBRO BASIN

Abstract We performed apatite and zircon (U-Th)/He dating on a granitic pluton that has been offset by ∼10 km by motion on the sinistral strike-slip Xiangcheng fault in SW Sichuan, SE Tibetan plateau, where the Shuoqu River incises a deep valley before joining the upper Yangtze River. Mean ZHe cooling ages range from 49.5 ± 2.2 Ma to 68.6 ± 6.0 Ma. Samples located above 3870 m yield mean apatite (U-Th)/He ages ranging from 30.6 ± 1.4 Ma to 40.6 ± 2.7 Ma, whereas samples at lower elevations range from 9.8 ± 1.3 Ma to 14.6 ± 2.7 Ma. In the same region, Cenozoic continental sediments are exposed on the flanks of deep valleys. They consist of unsorted conglomerates and sandstones that partly fill a paleotopography. The sediments were deposited during an episode of rapid sedimentation, followed by incision that varies between 0.5 and 1.2 km. Thermal and exhumational modeling of the granite thermochronometric data indicates rapid cooling during the middle Miocene that was likely related to fluvial incision. Our findings suggest that the upper Yangtze River and its tributary (Shuoqu) were connected by the middle Miocene. Our modeling also supports the idea that the exhumation pattern during the Cenozoic in the southeastern margin of the Tibetan Plateau is spatially and temporally heterogeneous.

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Cenozoic Sedimentation Along the Piedmonts of Thrust Related Basement Ranges and Strike-Slip Deformation Belts of the Iberian Variscan Massif

The Geology of Iberia: A Geodynamic Approach - Regional Geology Reviews ◽

10.1007/978-3-030-11190-8_5 ◽

2019 ◽

pp. 131-165 ◽

Cited By ~ 3

Author(s):

Pedro P. Cunha ◽

G. de Vicente ◽

F. Martín-González

Keyword(s):

Strike Slip ◽

Slip Deformation

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Shallow Seismic Reflection Survey of the Bootheel Lineament Area, Southeastern Missouri

Seismological Research Letters ◽

10.1785/gssrl.63.3.285 ◽

1992 ◽

Vol 63 (3) ◽

pp. 285-295 ◽

Cited By ~ 17

Author(s):

Eugene S. Schweig ◽

Fan Shen ◽

Lisa R. Kanter ◽

Eugene A. Luzietti ◽

Roy B. VanArsdale ◽

...

Keyword(s):

Seismic Reflection ◽

Strike Slip ◽

Seismic Reflection Data ◽

Reflection Data ◽

Shallow Seismic ◽

Slip Deformation ◽

Flower Structures

Abstract During 1990 we collected eight lines (11.5 km) of shallow seismic reflection data across the Bootheel lineament, a discontinuous feature that extends about 135 km in a north-northeast direction through northeastern Arkansas and southeastern Missouri. The profiles image reflectors at depths between about 55 m to 800 m. Gentle folding with wavelengths of about 800 m and amplitudes of 10 m to 25 m is evident on nearly every profile, generally coinciding with the surface traces of the lineament. We interpret our lines to show a complex zone of strike-slip deformation consisting of multiple flower structures, with deformation at least as young as the Eocene/Quaternary unconformity.

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