The deep electrical structure of southern taiwan and its tectonic implications

Chih Wen Chiang, Chien Chih Chen, Martyn Unsworth, Edward Bertrand, Chow Son Chen, Thong Day Kieu, Han Lun Hsu

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

The Taiwan orogen has formed as a result of the arc-continent collision between the Eurasian continental margin and the Luzon volcanic arc over the last 5 million years and is the type example of an arc-continent collision. The tectonic processes at work beneath Taiwan are still debated; the available data have been interpreted with both thin-skinned and lithospheric collision models. In 2004, the Taiwan Integrated Geodynamical Research (TAIGER) project began a systematic investigation of the crustal and upper mantle structure beneath Taiwan. TAIGER magnetotelluric (MT) data from central Taiwan favor a thick-skinned model for that region. The Taiwan orogen becomes younger to the south, so the earlier stages of collision were investigated with a 100-km-long MT profile in southern Taiwan at latitude of 23.30N. Data were recorded at 15 MT sites and tensor decomposition and two-dimensional inversion were applied to the MT data. The shallow electrical resistivity structure is in good agreement with surface geology. The deeper structure shows a major conductor in the mid-crust that can be explained by fluid content of 0.4 -1.4%. A similar feature was observed in central Taiwan, but with a higher fluid content. The conductor in southern Taiwan extends to lower crustal depths and is likely caused by fluids generated by metamorphic reactions in a thickened crust. Together the central and southern Taiwan MT profiles show a crustal root beneath the Central Range.

Original languageEnglish
Pages (from-to)879-895
Number of pages17
JournalTerrestrial, Atmospheric and Oceanic Sciences
Volume21
Issue number6
DOIs
StatePublished - Dec 2010

Keywords

  • Arc-continent collision
  • Electrical structure
  • Magnetotellurics
  • Taiwan tectonics

Fingerprint

Dive into the research topics of 'The deep electrical structure of southern taiwan and its tectonic implications'. Together they form a unique fingerprint.

Cite this