Structure and seismic stratigraphy of South Pengchiahsu Basin, northern offshore Taiwan /
| Main Author: | |
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1993.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | The South Pengchiahsu Basin is bounded by Tungyintao Ridge-Kuanyin Uplift and Taiwan-Sinzi Folded Zone on the west and the east; on the north, it is separated from the North Pengchiahsu Basin by Pengchiahsu Platform. It abuts Taiwan to the south. It is a rifting and marginal basin of the continental shelf in the East China Sea. The basin is filled with a thick succession of Cenozoic sediments derived principally from mainland China. The initial phase of basin extension occurred in the Late Paleocene. Cross sections of the basin show a series of mainly asymmetrical half-grabens. It is characterized by opposite, partly overlapping half-graben systems linked by an interference accommodation zone which forms the local structural high. Of the three major half-grabens, one is related to the main phase of extension, whereas the others are due to local normal faulting. The basin has been undergone two stages of reactivated thrust tectonic events in Middle Miocene and Late Pliocene. Based on the seismic section, fault map and isochron map, the right-lateral strike-slip fault may exist near the southwest margin of the basin. The synrift and postrift sequences are separated by a widespread angular unconformity. The Late Paleocene initial rift phase was characterized by fan-delta deposits in semi-closed lakes. A major rift phase with rising sea level and subsidence occurred in Early Eocene time during which deep-water sedimentary facies were deposited. Lowstand prograding complex-fan delta systems were deposited in the basin with falling sea level at the beginning of Middle Eocene. The deposition of Late Eocene and possibly Early Oligocene deltaic systems marks the final stage of synrift basin. The vertical sedimentary variation is typically upward from fan-delta and semi-closed lacustrine (sequence A) to deep-water facies (sequence B) to prograding complex and deltaic (sequence C and D) to fluvial (postrift sequence E). Sea-level change and extensional tectonics may control the distribution and thickness of the sediments in synrift sequences. Several potential hydrocarbon plays were inferred due to the good reservoirs, source rocks and maturity in high geothermal gradient. |
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| Item Description: | Vita. "Major subject: Geophysics." |
| Physical Description: | xiii, 116 leaves : illustrations ; 28 cm |
| Bibliography: | Includes bibliographical references. |