Lake-type controls on sedimentary infill and petroleum source rocks in the Palaeogene Fushan Depression, Beibuwan Basin, South China
Lake-type controls on sedimentary infill and petroleum source rocks in the Palaeogene Fushan Depression, Beibuwan Basin, South China
复制标题
北部湾盆地古近系福山凹陷湖泊类型对沉积充填及油气源岩的控制
DOI：
10.1002/gj.3634
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发表时间：
2020
影响因子：
1.8
通讯作者：
Chen Shanbin
中科院分区：
文献类型：
--
作者：
Jin Siding;Wang Hua;Cao Haiyang;Gan Huajun;Chen Shanbin
北部湾湖相盆地位于南中国海北部陆架，蕴藏着丰富的油气资源。由于湖盆的沉积学非常复杂，与勘探有关的重大财务风险需要通过具体的技术或大幅增加对湖系的了解来减少。通过对北部湾盆地浮山凹陷沉积充填、层序地层学和有机地球化学的研究，加深了对沉积物供水率(气候变化)与潜在可容纳空间(构造沉降和继承性地形)变化之间成因关系的认识。本文报道了福山凹陷两个独立凹陷中发育的两个不同的湖型演化旋回，它们的特征是：(A)超充填，(B)平衡充填，(C)超充填，(D)平衡充填，(E)超充填，以及(A)超充填，(B)平衡充填，(C)在白莲凹陷和华厂转换带中部超充填。气候变化是这两个凹陷前三期湖型演化的主导因素，而伸展构造环境是黄铜凹陷第四期和第五期湖型演化的控制因素。相同的湖泊类型、相似的源岩和储集层性质以及观察表明，这些源岩和储集层元素的组合出现在各种各样的构造环境中。此外，福山凹陷湖型演化旋回过程的发现，对类似构造气候背景下的其他类似湖盆的研究也具有一定的借鉴意义。
The lacustrine Beibuwan Basin contained large petroleum reserves in the northern continental shelf of the South China Sea. Due to the great sedimentologic complexity of the lacustrine basins, a significant financial risk associated with exploration needed to be reduced by specific techniques or significantly increasing knowledge of the lake system. Sedimentary infill, sequence stratigraphy, and organic geochemistry of the Fushan Depression in the Beibuwan Basin were studied, and enhanced our comprehension of the genetic relations between the sediment + water supply rates (climate change) and potential accommodation (tectonic subsidence and inherited topography) change. Here, we report two different lake‐type evolution cycles developed in two separated sags in the Fushan Depression, which are characterized by: (a) overfilled, (b) balanced‐fill, (c) overfilled, (d) balanced‐fill, and (e) overfilled in the Huangtong Sag, and (a) overfilled, (b) balanced‐fill, and (c) overfilled in the Bailian Sag and the centre Huachang Transfer Zone. Climate change is the dominant factor in the first three phases of the lake‐type evolution in both two sags, and transtensional tectonic setting is the controlling factor in the fourth and fifth phases of the lake‐type evolution in the Huangtong Sag. The same lake‐type with similar source rock and reservoir properties and observations indicate that these associations of source rock and reservoir play elements occur in a wide variety of tectonic settings. Moreover, the discovery of the cyclical process of the lake‐type evolution in the Fushan Depression can be a reference in the study of other similar lacustrine basins under an analogous tectonic and climate background.