Skip to Main content Skip to Navigation
Journal articles

Stable Rate of Slip Along the Karakax Section of the Altyn Tagh Fault from Observation of Interglacial and Postglacial Offset Morphology and Surface Dating

Abstract : Digital elevation maps obtained using TanDEM‐X and Pleiades data combined with newly obtained surface age estimates using cosmogenic radionuclide (CRN) and optically simulated luminescence (OSL) methods are used to quantify the slip rate along the western section of the Altyn Tagh Fault in southern Xinjiang. The reconstruction of the conical shape of massive alluvial fans inferred to be from the Eemian (115±7 ka) from CRN dating shows consistent left‐lateral offsets of 300±20 m, yielding a slip rate of 2.6±0.3 mm/year. Successive episodes of incision have left cut terraces inset in wide canyons, 10–25 m below the fans' surface. The incision was followed by the deposition of a broad terrace of early Holocene age, which is reincised by modern stream channels. Near the village of Shanxili, a 200 m wide valley is partially dammed by a shutter ridge displaced by the fault. A fill terrace deposited upstream from the ridge has an OSL age of 8.8±0.6 ka. The 23±2 m offset of the riser incising the terrace indicates a minimum postdepositional movement on the fault, yielding a Holocene rate of 2.6±0.5 mm/year, consistent with the 115‐ka average slip rate. Scarp degradation analysis using mass diffusion reveals a nonlinear relationship between fault displacement and degradation coefficient along the progressively exposed fault scarp, a pattern suggesting either seismic clustering or variable diffusion rate since the Eemian. Together with the Gozha Co‐Longmu Co fault to the south, the Karakax section of the Altyn Tagh Fault contributes to the eastward movement of the western corner of Tibet.
Document type :
Journal articles
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-03062308
Contributor : James Hollingsworth <>
Submitted on : Friday, April 16, 2021 - 7:51:09 AM
Last modification on : Saturday, April 17, 2021 - 3:28:28 AM

File

2019JB018893.pdf
Publisher files allowed on an open archive

Identifiers

Collections

Citation

Gilles Peltzer, Nathan Brown, Anne‐sophie Mériaux, Jerome van der Woerd, Edward Rhodes, et al.. Stable Rate of Slip Along the Karakax Section of the Altyn Tagh Fault from Observation of Interglacial and Postglacial Offset Morphology and Surface Dating. Journal of Geophysical Research : Solid Earth, American Geophysical Union, 2020, 125 (5), ⟨10.1029/2019JB018893⟩. ⟨hal-03062308⟩

Share

Metrics

Record views

73

Files downloads

67