Evolutionary characteristics of the sags to the east of Tan–Lu Fault Zone, Bohai Bay Basin (China): Implications for hydrocarbon exploration and regional tectonic evolution

A method of identifying lithostratigraphic traps based on seismic sedimentology is proposed. We first establish a 3D high-resolution (fifth-order) sequence stratigraphic framework by using the stratal slices. Then, the reservoir distribution and reservoir-seal assemblage are investigated within the high-resolution sequence framework. This method turns the interpretation of lithostratigraphic traps from traditional seismic facies-based approach to the dynamic analysis of high-resolution seismic geomorphic information. We divide the lower Sha-1 member in the Banqiao Sag, Bohai Bay Basin, East China, into fourth- and fifth-order sequences by applying our method. The fifth-order sequence corresponding to Sha1-2 shows that the fan delta-distal subaqueous fan depositional system can be observed at the bottom of Sha1-2. The bounding fault and paleogeomorphology control the deposition of sand, whereas the sand bodies in the fan delta and distal subaqueous fan are developed near the bounding fault and the open lake basin, respectively. We then predict the sand thickness based on the well logs and seismic amplitudes. Moreover, according to the structural features, at least four lithostratigraphic traps are identified. These traps form a good reservoir-seal assemblage with overlying mudstones deposited during the period of lacustrine level rising. The drilling results in Trap-3 suggest that, our method can be a method of choice for effectively identifying the lithostratigraphic traps, a significant measure for hydrocarbon exploration.

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Organic geochemical and petrophysical characteristics of saline lacustrine shale in the Dongpu Depression, Bohai Bay Basin, China: Implications for Es3 hydrocarbon exploration

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2019.106546 ◽

2020 ◽

Vol 184 ◽

pp. 106546

Author(s):

Ke Wang ◽

Xiongqi Pang ◽

Hongan Zhang ◽

Tao Hu ◽

Tianwu Xu ◽

...

Keyword(s):

Hydrocarbon Exploration ◽

Bohai Bay ◽

Bohai Bay Basin ◽

Dongpu Depression ◽

Lacustrine Shale ◽

Saline Lacustrine

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The facies analysis of a fan delta by integrating multiple discipline data — A case study of the KL-A oilfield, Bohai Bay Basin, China

Interpretation ◽

10.1190/int-2019-0083.1 ◽

2020 ◽

Vol 8 (2) ◽

pp. SF21-SF35 ◽

Cited By ~ 1

Author(s):

Zhijun Yin ◽

Bo Zhang ◽

Yue Hu ◽

Jianmin Zhu ◽

Cheng Guo ◽

...

Keyword(s):

Horizontal Distribution ◽

Hydrocarbon Exploration ◽

Well Logs ◽

Bohai Bay ◽

Bohai Bay Basin ◽

Fine Grained ◽

Facies Classification ◽

Fan Delta ◽

Mouth Bar ◽

Rms Amplitude

The third member of the Shahejie Formation (Es3) is the main hydrocarbon exploration target in the KL-A oilfield, Bohai Bay Basin, East China. The facies classification is an essential step in mapping the depositional system of Es3 within the Bohai Bay Basin. The facies model is important for identifying the “sweet” lithology within the reservoirs. We characterize the facies of Es3 by integrating cores, well logs, and seismic data. The analysis indicates that the Es3 consists of fan delta deposits. The analysis using well logs and cores indicates that there are five different lithofacies for the Es3 Formation: massive sandstone, horizontally bedded sandstone, trough cross-bedded sandstone, ripple cross-laminated sandstone, and massive mud. The microfacies of Es3 include distributary channel, distributary mouth bar, interdistributary bay, and lacustrine mudstone deposits. The sweet lithologies for hydrocarbon accumulation within the KL-A oilfield include the coarse- and fine-grained sand developed within the channels and distributary mouth bar. We use seismic rms amplitude strata slices to determine the horizontal distribution of facies of the fan delta. The correlation between rms amplitude and well logs indicates that relatively low rms amplitude anomalies on the strata slices can be used as an indicator for sandstone within the KL-A oilfield.

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The Depositional System of Dongying Formation and Subtle Reservoir Exploration in Sha’nan Structural Belt Qikou Sag of Bohai Bay Basin, China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.616-618.32 ◽

2012 ◽

Vol 616-618 ◽

pp. 32-37

Author(s):

Ren Li Qi ◽

Kai Yuan Chen ◽

Bo Niu ◽

Zhan Tao Xing

Keyword(s):

Analysis Data ◽

Hydrocarbon Exploration ◽

Seismic Facies ◽

Bohai Bay ◽

Bohai Bay Basin ◽

Hydrocarbon Source Rock ◽

Offshore Area ◽

Qikou Sag ◽

Sand Bar ◽

Geological Analysis

The subtle reservoir has become an important exploration target within the Bohai Bay Basin, especially in the Qikou sag. In order to guide subtle reservoirs exploration in offshore area geological analysis to Sha’nan structural belt is carried out in this paper. Qikou sag has large thickness, high abundance, ideal type hydrocarbon source rock. By unconformity recognition technique and paleotectonic analysis technique, results show that tectonic uplift had provided sedimentary source to the depression around it after Es1. By 3-D seismic interpretation technique and Seismic facies analysis, the sedimentary facies was confirmed. Geological analysis results show that sand bar, subaqueous fan is developed around it in Ed3. With the new geological analysis data sedimentary model of Sha’nan structural belt has been built in this paper. The sand bar and subaqueous fans showed a good reservoir potential, which are advantageous to oil accumulations. The southern part of Sha’nan structural belt has good hydrocarbon exploration potential.

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