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    Volume 42 Issue 11
    Nov.  2017
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    Article Contents
    Zhao Pengfei, Yang Xianghua, Zhang Huilai, Bu Fanqing, Wu Jing, 2017. The Sedimentary Architecture Characteristics and Fluid System of the Deep Sea Turbidite-Lobe Complex Sandbodies:A Case Study of the Deep-Water Region in the Niger Delta Front. Earth Science, 42(11): 1972-1983. doi: 10.3799/dqkx.2017.125
    Citation: Zhao Pengfei, Yang Xianghua, Zhang Huilai, Bu Fanqing, Wu Jing, 2017. The Sedimentary Architecture Characteristics and Fluid System of the Deep Sea Turbidite-Lobe Complex Sandbodies:A Case Study of the Deep-Water Region in the Niger Delta Front. Earth Science, 42(11): 1972-1983. doi: 10.3799/dqkx.2017.125

    The Sedimentary Architecture Characteristics and Fluid System of the Deep Sea Turbidite-Lobe Complex Sandbodies:A Case Study of the Deep-Water Region in the Niger Delta Front

    doi: 10.3799/dqkx.2017.125
    • Received Date: 2017-02-15
    • Publish Date: 2017-11-15
    • The turbidite lobe complex sandbodies of the Niger Delta front are major oil and gas exploration targets in the deep-water area of the West Africa. But the study of the sedimentary architecture and fluid system is still insufficient. Based on the seismic facies, seismic attributes, core data and drilling reservoir correlation analysis, the characteristics of the sedimentary architecture and geological characteristics of the reservoirs in the study area were comprehensively studied. Besides, the fluid system of the lobe complex sandbodies is also discussed according to the MDT (mouldar formation dynamics tester) and DST (drill stem testing) data. In seismic profiles, the lobe complex sandbodies always with moderate amplitude characteristics and multiple stages can be seen upward. The sandbodies display migration in both lateral and along the paleocurrent direction and present meandering strip on the plane. The log facies of the complex sandbodies mainly correspond to bell shaped-box type, and always with a mutation contact with surrounding mudstone. Each lobe is composed of main lobe and side lobe, and the gravity flow channel is widely developed. The massive sandstone is a high quality reservoir in the oilfield, and the distribution area of the sandbodies is relatively on large scale. The sandbodies developed several sets of fluid system and the lobe reservoir was controlled by mudstone thickness partition, which may have favorable conditions to form a simple and unified pressure system with sufficient water energy. Thus, the sedimentary architecture of the complex sandbodies in the K oilfield is clear, and it has a unified fluid system, which can be used as a typical example of the petroleum exploration in the deep water area and mud-rich setting.

       

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