Late Triassic tectono-volcanic activity and resulting soft-sediment deformation structures in the Yanchang Formation (Ordos Basin, China)

Yi Gao, Zaixing Jiang, Jingong Zhang, Shengqian Liu, James L. Best, Daoqing Yang, A. J. van Loon

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

The Middle-Late Triassic Yanchang Formation, present in the large intracratonic Ordos Basin, is built of alternating sandstones, mudstones, and tuffs, representing a complete lacustrine cycle. Cores from wells in the south-western part of the basin show various types of soft-sediment deformation structures, particularly contorted lamination/bedding, load casts, and associated structures (flame structures, pseudonodules), penecontemporaneous faults, injection structures, and sandy and muddy slumps. They originated by liquefaction and fluidization of unconsolidated sediments, as well as by brittle fracturing of semiconsolidated sediments. Seismic events resulting from synsedimentary tectonic activity were the main triggers but sedimentary overloading may locally have been a minor trigger. The volcanic tuffs support tectono-volcanic activity. The deformation structures are clustered in three stratigraphic levels, indicating phases of intensified seismic activity. A thick extensive oil shale, with various deformation structures, reveals another active tectonic phase. These four intervals coincide well with the transition of the sedimentary architecture in the area.

Original languageEnglish (US)
Title of host publicationThe Ordos Basin
Subtitle of host publicationSedimentological Research for Hydrocarbons Exploration
PublisherElsevier
Pages371-393
Number of pages23
ISBN (Electronic)9780323852647
ISBN (Print)9780323852654
DOIs
StatePublished - Jan 1 2021

Keywords

  • Lake evolution
  • Ordos Basin
  • Soft-sediment deformation structures
  • Tectono-volcanic activity
  • Yanchang Formation

ASJC Scopus subject areas

  • Economics, Econometrics and Finance(all)
  • General Business, Management and Accounting

Fingerprint

Dive into the research topics of 'Late Triassic tectono-volcanic activity and resulting soft-sediment deformation structures in the Yanchang Formation (Ordos Basin, China)'. Together they form a unique fingerprint.

Cite this