The thermal imprint of continental breakup during the formation of the South China Sea

Michael Nirrengarten* (Corresponding Author), Geoffroy Mohn, Andrea Schito, Sveva Corrado, Laura Gutiérrez-García, Stephen Bowden, Frank Despinois

*Corresponding author for this work

Research output: Contribution to journalArticle

2 Citations (Scopus)
3 Downloads (Pure)

Abstract

The stretching of continental lithosphere results in asthenospheric upwelling, raising of isotherms, melting during decompression and eventually seafloor spreading. The thermal maturity of overlying sedimentary organic matter from these settings would be expected to be distinctly altered by these processes, however this is still poorly constrained and quantitatively unexplored. International Ocean Discovery Program (IODP) Expeditions 367-368 cored sediments at the Continent Ocean Transition (COT) on the Northern Margin of the South China Sea (SCS). From two settings at the South East China COT we measured and modelled thermal maturity in pre-/syn- to post-rift sediments making use of a range of thermal maturity parameters. Various heat-flow evolutionary scenarios were investigated, with notable jumps in thermal maturity for sediments corresponding to different depositional packages. In order to match observations of thermal maturity, it was found that the deeper and likely pre-rift sediments were heated to temperatures as high as 200°C during initial break up. Achieving this temperature for the deeper sediments requires that significant additional heat be imparted at shallow depths (e.g. exposure to at least the far-field effects of a magmatic intrusion or subsurface expressions of volcanism). The post-rift sediments have lower thermal maturities which are likely due to limited burial and the absence of late post-rift magmatism. The comparison of the SE China COT with other margin examples highlights some parameters controlling the thermal evolution and its record.
Original languageEnglish
Article number115972
JournalEarth and Planetary Science Letters
Volume531
Early online date6 Dec 2019
DOIs
Publication statusPublished - 1 Feb 2020

Keywords

  • continental breakup
  • thermal evolution
  • SE China distal margin
  • IODP
  • organic petrography
  • Raman spectroscopy
  • biomarker analysis
  • SE China Margin
  • IODP 367-368
  • RAMAN-SPECTRA
  • EASTERN GULF
  • CRUSTAL EXTENSION
  • CARBONACEOUS MATERIAL
  • ORGANIC-MATTER
  • MARGIN
  • EVOLUTION
  • SEDIMENTARY BASINS
  • NEWFOUNDLAND
  • HEAT-FLOW

Fingerprint Dive into the research topics of 'The thermal imprint of continental breakup during the formation of the South China Sea'. Together they form a unique fingerprint.

  • Cite this

    Nirrengarten, M., Mohn, G., Schito, A., Corrado, S., Gutiérrez-García, L., Bowden, S., & Despinois, F. (2020). The thermal imprint of continental breakup during the formation of the South China Sea. Earth and Planetary Science Letters, 531, [115972]. https://doi.org/10.1016/j.epsl.2019.115972