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| Titel |
Tectonic-depositional environment and proto-type basins evolution of the Late Ordovician in the Tarim Basin |
| VerfasserIn |
Huahua Gao, Dengfa He, Xiaoguang Tong, Zhixin Wen, Zhaoming Wang |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250147110
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| Publikation (Nr.) |
 EGU/EGU2017-11218.pdf |
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| Zusammenfassung |
| The tectonic-depositional environment of the Tarim Basin underwent a rapid and dramatic
change in the Late Ordovician. The restoration of the proto-type basins has a great
significance for the reveal of the basin-mountain coupling and basin fill process. Based on the
newest data of drillings, seismic profiles and outcrops, with the analysis of sedimentary facies
and the combination of basins and orogenic belts, this paper reconstructed the Late
Ordovician tectonic-depositional environment of the Tarim Basin and established the models
of basin-mountain couplings and basin fill processes, by employing the method of “point
→ line → face”. In the Tumuxiuke Formation stage, the inundated platform-deep
water basin sedimentary system was developed in the western part of the Tarim
Basin and the Bachu-Tazhong area was denudated ; In the Lianglitage Formation
stage, the open platform-deep water basin sedimentary system was developed and
the Yudong-Tanggubasi area underwent the transition from the carbonate basin
to the turbidite basin; in the Sangtamu Formation stage, the mixed shelf deposit-
turbidite basin sedimentary system was developed and the under-filling deposit was
only developed in the Kalpin; In the Tierekeawati Formation stage, the shore-shelf
sedimentary system was developed. In the Tumuxiuke Formation- Sangtamu Formation
stages, the turbidite basin sedimentary system was continually developed in the
eastern part of the Tarim Basin; In the Tierekeawati Formation stage, the clastic
shelf sedimentary system was developed in this area. The tectonic-depositional
pattern of Tarim Basin in the Late Ordovician had the feature as the following:
the platform-basin pattern differentiated from east to west was overlaid with the
uplift-depression pattern differentiated from north to south. In the Tumuxiuke Formation
stage, the unified platform in the west of the basin had broken down leading to the
development of uplift-depression pattern differentiated from north to south. In the
Lianglitage Formation-Sangtamu Formation stages, the subsidence and deposition fill
occurred overall the basin, the depression died out making the depocenter reversed. In
the Tierekeawati Formation stage, the northern and southern part of basin uplifted
severely and became land, only the middle part of the basin was covered by water,
marking the formation of the uplift-depression pattern differentiated from north to
south. Under the background that the coupling between basins and orogenic belts
increasingly strengthened, the injection of large terrigenous clastics and the up and
down of topography made tectonic-depositional environment change rapidly. At the
end of the Ordovician, with the sea level descended drastically and the emergence
of provenance basin within the basin, the Tarim Basin terminated the history that
carbonate sediment grew extensively, signing that basin evolution entered into a new
stage.
Key words: tectonic-depositional environment; proto-type basin; Late Ordovician; Tarim
basin |
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