Sedimentary facies and evolution in the Qiantang River incised valley, eastern China

2005 ◽  
Vol 219 (4) ◽  
pp. 235-259 ◽  
Author(s):  
Chun-Ming Lin ◽  
Hong-Chun Zhuo ◽  
Shu Gao
Keyword(s):  
Eastern China ◽  
Sedimentary Facies ◽  
Incised Valley ◽  
Qiantang River

Features and sealing mechanism of shallow biogenic gas in incised valley fills (the Qiantang River, eastern China): A case study

2010 ◽  
Vol 27 (4) ◽  
pp. 909-922 ◽  
Author(s):  
Chun-Ming Lin ◽  
Yan-Li Li ◽  
Hong-Chun Zhuo ◽  
George W. Shurr ◽  
Jennie L. Ridgley ◽  
...  
Keyword(s):  
Eastern China ◽  
Incised Valley ◽  
Biogenic Gas ◽  
Qiantang River ◽  
Valley Fills ◽  
Sealing Mechanism

Predictive distribution of high-quality tight reservoirs of coarse clastic rocks by linking diagenesis to sedimentary facies: Evidence from the upper Sha 4 Member in the northern Bonan Sag, Bohai Bay Basin, eastern China

2018 ◽  
Vol 6 (2) ◽  
pp. T413-T429 ◽  
Author(s):  
Dong Wu ◽  
Xiantai Liu ◽  
Yushan Du ◽  
Long Jiang ◽  
Ziyan Cheng
Keyword(s):  
Eastern China ◽  
Sedimentary Facies ◽  
Middle Part ◽  
Bohai Bay ◽  
Bohai Bay Basin ◽  
High Quality ◽  
Clastic Rocks ◽  
Bonan Sag ◽  
Tight Reservoirs ◽  
Channel Deposits

Coarse clastic rocks of the upper Sha 4 Member in the northern Bonan Sag of the Bohai Bay Basin in eastern China are important hydrocarbon reservoirs. The deposits are tight reservoirs owing to the low porosity (less than 10%) and low permeability (less than 1 mD). Because of the strong heterogeneity, although the reserve in the northern Bonan Sag is remarkable, only 4.9% of the reserves are recovered. We have studied these tight reservoirs by linking diagenesis to sedimentary facies to help predict the distribution of high-quality tight reservoirs. Petrographic analysis is undertaken based on cores, thin sections, X-ray diffraction and scanning electron microscope, helpful to understand the impacts on tight reservoirs of sedimentary factors and diagenesis factors. Sedimentary microfacies, lithologic characteristics, reservoir property, diagenesis, and diagenetic minerals are studied. Coarse clastic rocks are deposited mainly in nearshore subaqueous fans and fan deltas. The multistage sandstones are the valid reservoirs of coarse clastic rocks and dominated by feldspathic litharenite, lithic arkose, and arkose. The reservoir property is poor principally owing to the strong compaction and cementation. Pores are composed of secondary pores and primary pores. The secondary pore, generated in the dissolution of detrital minerals and/or cements, is the major type of pores and important to porosity improvement. By linking diagenesis to sedimentary facies, it can be concluded that high-quality tight reservoirs of coarse clastic rocks of the upper Sha 4 Member in the northern Bonan Sag of Bohai Bay Basin in eastern China are associated with medium to coarse-grain sandstones, found in the middle part of underwater distributary channel deposits in fan deltas and in the middle part of underwater channel deposits in nearshore subaqueous fans, with abundant secondary porosity but low cement contents, vertically at depths ranging from 3500 to 4100 m.

scholarly journals Multi-disciplinary approach to sedimentary facies analysis of Messinian Salinity Crisis tectono-sequences (South-Mansoura Area, Nile Delta): Incised-valley fill geological model reconstruction and petroleum geology–reservoir element delineation

2021 ◽  
Vol 11 (4) ◽  
pp. 1643-1666
Author(s):  
Ahmed M. Elatrash ◽  
Mohammad A. Abdelwahhab ◽  
Hamdalla A. Wanas ◽  
Samir I. El-Naggar ◽  
Hasan M. Elshayeb
Keyword(s):  
Reservoir Characterization ◽  
Nile Delta ◽  
Sedimentary Facies ◽  
Reservoir Quality ◽  
Well Log ◽  
Geological Model ◽  
Depositional Facies ◽  
Incised Valley ◽  
Valley Fill

AbstractThe quality of a hydrocarbon reservoir is strongly controlled by the depositional and diagenetic facies nature of the given rock. Therefore, building a precise geological/depositional model of the reservoir rock is critical to reducing risks while exploring for petroleum. Ultimate reservoir characterization for constructing an adequate geological model is still challenging due to the in general insufficiency of data; particularly integrating them through combined approaches. In this paper, we integrated seismic geomorphology, sequence stratigraphy, and sedimentology, to efficiently characterize the Upper Miocene, incised-valley fill, Abu Madi Formation at South Mansoura Area (Onshore Nile Delta, Egypt). Abu Madi Formation, in the study area, is a SW-NE trending reservoir fairway consisting of alternative sequences of shales and channel-fill sandstones, of the Messinian age, that were built as a result of the River Nile sediment supply upon the Messinian Salinity Crisis. Hence, it comprises a range of continental to coastal depositional facies. We utilized dataset including seismic data, complete set of well logs, and core samples. We performed seismic attribute analysis, particularly spectral decomposition, over stratal slices to outline the geometry of the incised-valley fill. Moreover, well log analysis was done to distinguish different facies and lithofacies associations, and define their paleo-depositional environments; a preceding further look was given to the well log-based sequence stratigraphic setting as well. Furthermore, mineralogical composition and post-depositional diagenesis were identified performing petrographical analysis of some thin sections adopted from the core samples. A linkage between such approaches, performed in this study, and their impact on reservoir quality determination was aimed to shed light on a successful integrated reservoir characterization, capable of giving a robust insight into the depositional facies, and the associated petroleum potential. The results show that MSC Abu Madi Formation constitutes a third-order depositional sequence of fluvial to estuarine units, infilling the Eonile-canyon, with five sedimentary facies associations; overbank mud, fluvial channel complex, estuarine mud, tidal channels, and tidal bars; trending SW-NE with a Y-shape channel geometry. The fluvial facies association (zone 1 and 3) enriches coarse-grained sandstones, deposited in subaerial setting, with significantly higher reservoir quality, acting as the best reservoir facies of the area. Although the dissolution of detrital components, mainly feldspars, enhanced a secondary porosity, improving reservoir quality of MSC Abu Madi sediments, continental fluvial channel facies represent the main fluid flow conduits, where marine influence is limited.

14C GEOCHRONOLOGY AND RADIOCARBON RESERVOIR EFFECT OF REVIEWED LAKES STUDY IN CHINA

Radiocarbon ◽  
2021 ◽  
pp. 1-12
Author(s):  
Weijian Zhou ◽  
Yuda Chui ◽  
Ling Yang ◽  
Peng Cheng ◽  
Ning Chen ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Piecewise Linear ◽  
Eastern China ◽  
Lacustrine Sediments ◽  
Sedimentary Facies ◽  
Northwest China ◽  
Tibet Plateau ◽  
Dominant Factor ◽  
Climatic Regions ◽  
Reservoir Age

ABSTRACT Lacustrine sediments are important archives for paleoclimate research, but there are evident carbon reservoir effects. Radiocarbon (14C) ages of lake sediments must be corrected for these effects before applying them to paleoclimate research. The authors review the lacustrine research from the last 20 years from different climatic regions in China, and systematically investigate the 14C age and correction methods used in the studies of 81 lakes. It is found that the climate-vegetation cover and distribution of carbonate around lakes are dominant factor controlling radiocarbon reservoir effects. In eastern China, the average 14C reservoir age is about 500 14C years and is associated with relatively dense vegetation. However, in northwest China and Qinghai-Tibet Plateau, widespread carbonate bedrock may markedly increase the radiocarbon reservoir age which frequently is about 1500 and 2500 14C years. A piecewise linear regression model provides more reliable 14C reservoir age correction that accounts for sedimentary facies and sedimentation rate changes. It is worth mentioning that when analyzing 14C ages deviated greatly from time sequence, the age anomalies may indicate important effects relevant to the study of climate and environmental changes.

Sign in / Sign up

Export Citation Format

Share Document