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| Titel |
Relative role of transfer zones in controlling sequence stacking patterns and facies distribution: insights from the Fushan Depression, South China Sea |
| VerfasserIn |
Entao Liu, Hua Wang, Yuan Li, Chuanyan Huang |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250103149
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| Publikation (Nr.) |
 EGU/EGU2015-2547.pdf |
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| Zusammenfassung |
| In sedimentary basins, a transfer zone can be defined as a coordinated system of
deformational features which has good prospects for hydrocarbon exploration. Although the
term “transfer zone” has been widely applied to the study of extensional basins, little
attention has been paid to its controlling effect on sequence tracking pattern and depositional
facies distribution. Fushan Depression is a half-graben rift sub-basin, located in the southeast
of the Beibuwan Basin, South China Sea. In this study, comparative analysis of
seismic reflection, palaeogeomorphology, fault activity and depositional facies
distribution in the southern slope indicates that three different types of sequence stacking
patterns (i.e. multi-level step-fault belt in the western area, flexure slope belt in
the central area, gentle slope belt in the eastern area) were developed along the
southern slope, together with a large-scale transfer zone in the central area, at the
intersection of the western and eastern fault systems. Further analysis shows that the
transfer zone played an important role in the diversity of sequence stacking patterns in
the southern slope by dividing the Fushan Depression into two non-interfering
tectonic systems forming different sequence patterns, and leading to the formation
of the flexure slope belt in the central area. The transfer zone had an important
controlling effect on not only the diversity of sequence tracking patterns, but also
the facies distribution on the relay ramp. During the high-stand stage, under the
controlling effect of the transfer zone, the sediments contain a significant proportion of
coarser material accumulated and distributed along the ramp axis. By contrast, during
the low-stand stage, the transfer zone did not seem to contribute significantly to
the low-stand fan distribution which was mainly controlled by the slope gradient
(palaeogeomorphology). Therefore, analysis of the transfer zone can provide a new
perspective for basin analysis. In addition, the transfer zone area demonstrated
unique hydrocarbon accumulation models different from the western and eastern
areas. It was not only a structural high combined with sufficient coarse-grained
reservoir quality sands, but was also associated with large-scale sublacustrine fan
deposits with high quality reservoirs, indicating that the recognition of transfer
zones can improve the prediction of hydrocarbon occurrences in similar settings. |
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