The Permian seamount stratigraphic sequence in Chiang Mai,North Thailand and its tectogeographic significance |
| |
| Authors: | QingLai Feng WenQiang Yang ShangYue Shen Chongpan Chonglakmani Kitsana Malila |
| |
| Institution: | (1) State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Wuhan, 430074, China;(2) School of Geotechnology, Suranaree University of Technology, Nakhon Ratchasima, Thailand |
| |
| Abstract: | The widespread Permian carbonate strata outcropped in northwestern Thailand are considered as the evidence for the Late Paleozoic
shallow Tethys. Our investigation, however, shows that basalt can be discovered usually under the Permian carbonate sequence
in Chiang Mai-Fang area, northwestern Thailand. The basalt belongs to subalkalic basalt and potassic trachybasalt. They are
characterized by high P and Ti in major elements, by high content, enriching LREE, lacking δEu anomaly in rare earth elements,
and by enrichment of the large ion lithophile element (LILE) (K, Rb, Ba) and high field strength element (HFSE) (Nb, Ta, Zr)
in trace elements, which can be compared with the characters of the oceanic island basalt in Three Rivers (Jinsha River, Lancang
River, and Nujiang River) area, southwestern China. Therefore, the Permian carbonate in the studied area was deposited on
a seamount, rather than on a stable carbonate platform. The oceanic basin is correlated to the Late Paleozoic ocean represented
by the Changning-Menglian Belt in southwestern China and they are a major basin of the Paleo-Tethyan Archipelagoes Ocean.
The result indicates nonexistence of a Shan-Thai Block in the Late Paleozoic.
Supported by the National Natural Science Foundation of China (Grant Nos. 40372105, 40772143), “111” Project (Grant No. B08030),
and Suranaree University of Technology, Thailand |
| |
| Keywords: | seamount stratigraphic sequence basalt Late Paleozoic North Thailand Paleo-Tethys |
| 本文献已被 SpringerLink 等数据库收录！ |
|
