Sedimentary association of alternated mudstones and tight sandstones in China’s oil and gas bearing basins and its natural gas accumulation

Zhu, Guangyou; Gu, Lijing; Jin, Sheng; Dai, Jianhua; Ding, Wenlong; Zhang, Jinchuan; Song, Lixin

doi:10.1016/j.jseaes.2012.01.008

Cited by 47 publications

(13 citation statements)

References 17 publications

(4 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Combining core observations and published works on depositional environments and basin evolution (Zou et al, ; Li, ; Zhu et al, ), we conclude that the Lower Cretaceous sandstones are mainly proximal fan delta deposits with various grain sizes. The following key facies associations have been distinguished (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…The Yin‐E Basin is located in the China‐Mongolia frontier area, forming the intersection of the Tarim Plate, Kazakhstan Plate, Siberia Plate and North China Plate (Zou et al, ; Zhu et al, ). The Chagan Sag is an important hydrocarbon producing sag in the east of Yin‐E Basin.…”

Section: Geological Settingmentioning

confidence: 99%

“…However, similar ideas have rarely been applied to the study of fan delta clastic deposits (South and Talbot, ). Petroliferous basins, such as Bohai Gulf Basin in E. China (Li, ), contain fan delta deposits: the common facies in deep lacustrine settings of rift basins (Zou et al, ; Zhu et al, ). Thus, the spatial and temporal diagenetic evolution analysis of different subfacies deposits in deep lacustrine fan delta depositional system could contribute to a better recognition or prediction of reservoir heterogeneity.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Facies controls on the distribution of diagenetic alterations in fan delta deposits: a case study from the Lower Cretaceous sandstone, Chagan Sag, Inner Mongolia, China

et al. 2016

View full text Add to dashboard Cite

By integrating diagenesis and sedimentary facies, the distribution of diagenetic alterations and their impacts on reservoir quality were investigated within a lacustrine fan delta depositional environment in the Lower Cretaceous of the Western sub‐sag in the Chagan Sag, Yin‐E Basin, northern China. Core observation and analyses of petrography and geochemistry of the sandstones revealed that the eogenetic alterations display spatial and temporal distribution patterns associated with sedimentary facies, including distributary channels of a fan delta front (DC), distributary bays (DB) and sheet sands (SS) and mouth bar (MB) (SS and MB are collectively referred to as S). Percolation of meteoric waters occurring in high permeability DC sandstones resulted in leaching of feldspar, the formation of kaolinite, as well as mechanical infiltrated clays around detrital grains. Conversely, the DB deposits containing abundant ductile lithic fragments were subjected to mechanical compaction and thus the development of a pseudomatrix. During a long burial residence time (the Early Cretaceous period) in a lacustrine environment, abundant early carbonate cements were precipitated, especially in the distal S sandstones. The sandstones lacking eogenetic cements were subjected to stronger mechanical compaction. Additionally, eogenetic alterations have an important impact on the distribution of the mesogenetic alterations. Sandstones containing few eogenetic cements or thin or discontinuous infiltrated clay rims around the detrital grains were subjected to quartz cementation. However, during the hydrocarbon generation stage, the most efficient percolation of meteoric waters and organic acid dissolved feldspar minerals and carbonate cements, resulted in DC sandstones having more intragranular and intergranular porosity. Owing to high matrix contents and early calcite cement contents, the DB and S sandstones had lower permeability and were rarely dissolved. During the late mesogenetic stage, late carbonate cements occurred in all sedimentary facies and iron and magnesium ions were released from the transformation from kaolinite to illite or to chlorite. The results from this study show possible diagenetic evolutionary pathways in the reservoir sandstones within the fan delta depositional environment, which in turn provides some insights into the controls on reservoir potential. Copyright © 2016 John Wiley & Sons, Ltd.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Geological Settingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Facies controls on the distribution of diagenetic alterations in fan delta deposits: a case study from the Lower Cretaceous sandstone, Chagan Sag, Inner Mongolia, China

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Despite these encouraged exploration successes, the Bashijiqike sandstones are typical tight gas sandstone reservoirs with high heterogeneity, poor porosity and permeability (Zhu et al, 2012). Exploration and development efforts of the Bashijiqike reservoirs were often challenged by the complicated pore-network characteristics.…”

Section: Introductionmentioning

confidence: 99%

Depositional and Diagenetic Controls on Pore Structure of Tight Gas Sandstone Reservoirs: Evidence from Lower Cretaceous Bashijiqike Formation in Kelasu Thrust Belts, Kuqa Depression in Tarim Basin of West China

et al. 2015

View full text Add to dashboard Cite

Deeply buried Lower Cretaceous Bashijiqike sandstones are important gas exploration targets in the Kelasu thrust belt, Kuqa Depression of Tarim Basin in China. The sandstones are characterized by low porosity, low permeability and strong microscopic heterogeneity due to diagenesis during their geologic history. Mineralogical, petrographic, and geochemical analyses combined with high-pressure mercury injection analysis have been used to investigate the diagenesis, diagenetic minerals, and their impact on reservoir quality. This article addresses the controls exerted by depositional parameters and diagenetic modifications on pore-network characteristics (porosity, pore types, sizes, shapes, and distribution), with the aim to unravel the formation mechanisms of this complex pore structures, and to improve the characterization and classification evaluation for the Bashijiqike sandstone reservoirs. The Bashijiqike sandstones are dominated by lithic arkoses and feldspathic litharenite. The pore system consists of intergranular macropores, intergranular micropores, and intragranular pores. Framework grains are generally heavily compacted. Authigenic quartz, authigenic feldspar, clay minerals and carbonates are the major pore-filling constituents. The pore structure is characterized by small pore radius and poor interconnectivity. Entry pressure reflects the microscopic pore network and macroscopic reservoir property characteristics. Pore structure characteristics are linked to the depositional parameters, type and degree of diagenesis. Clays do not control reservoir pore networks alone, and pores and pore throats are wider in coarser grained sandstones. Entry pressure decreases with the content of the rigid quartz. Compaction and cementation continue to decrease the pore-throat size, while dissolution enlarges pores and pore-throats radius. Considerable amounts of microporosity associated with clay minerals and altered grains contribute to the high entry pressure. Comprehensive Coefficient of Diagenesis (CCD), which considers the integrative effect of diagenesis, shows strong statistical correlations with entry pressure. CCD is an integrative modulus of diagenesis and physical property, and generally the higher the values are, the better the pore structure. It is suitable for quantitatively characterizing pore structure in tight gas sandstones. The results of this work can help assess pore-network characteristics like the Bashijiqike sandstones which had experienced strong diagenetic modifications during their geological history.

show abstract

“…Therefore, the temperature and pressure system often changed in the course of hydrocarbon migration, accumulation, accumulation and adjustment, and resulted in the complexity and diversity of hydrocarbon genesis. Both the geochemical analysis for oil and gas and the integrated study of petroleum geology play important roles in the aspects like hydrocarbon genesis, secondary alteration, accumulation process and mode (Dahl et al, 1999;Hanson et al, 2000;Sun et al, 1996;2009a;2009b;Wang et al, 2005;Zhang et al, 2000;2004a;2004b;Hao et al, 2008;Jiang et al, 2008;Zhu et al, 2011a;2012b;2012c). Up to now, over 3 billion tons of 3P oil reserves and more than 1 trillion cubic meter of natural gas have been discovered in the deep marine Ordovician carbonate reservoir of the Tarim Basin.…”

Section: Introductionmentioning

confidence: 99%

Accumulation Mechanism of Complicated Deep Carbonate Reservoir in the Tazhong Area, Tarim Basin

Zhou

2013

Energy Exploration & Exploitation

View full text Add to dashboard Cite

The Tazhong area is located in the hinterland of the Taklimakan Desert, where abundant hydrocarbon resources are contained in the deep Ordovician carbonate rocks. Great exploration results have been obtained in the Middle and Lower Ordovician Yingshan formation over recent years, and a large layered oil/gas field has been proven. The fluid properties of this reservoir are complicated, and it can be divided into condensate gas reservoir, volatile oil reservoir and oil reservoir in accordance with fluid component and PVT phase behavior. These reservoirs distribute in alternation horizontally, without apparent boundaries vertically. Based on the study and analysis on test, exploration and production data, it is believed that the diversity of fluid properties results from the multiphase uneven infusion action of oil and gas, especially the severity of gas cut at late stage: the reservoir suffered from severe gas cut became condensate gas reservoir, the one suffered from weak gas cut became volatile oil reservoir, and the one free from gas cut still keeps the original oil reservoir state. It is discovered through study that the strike-slip fault plays an important role in the occurrence of gas cut at late stage: it not only acted as the pathway of gas migration at late stage, but also had an important impact on the reformation of reservoir. The impact of reservoir nature on gas cut mainly finds expression in the difference of combination of reservoir space: the mutually connected large pore/cavity and fracture system was favorable for gas charge at late stage, where condensate gas reservoir was mostly formed; while the isolated pore/cavity where the tectoclase developed weakly was relatively sealed, was unfavorable for the sufficient infusion of natural gas at late stage, and usually keeps the original oil reservoir state or formed volatile oil reservoir. Based on the discussion to the factors that affect the severity of gas cut in the paleo-reservoir at late stage, this paper clarifies the accumulation mechanisms and controlling factors of different kinds of reservoirs, establishes the accumulation mode of 3 types of reservoirs, and this is very significant to the effective prediction of hydrocarbon distribution in the deep carbonate rocks of the Tazhong area.

show abstract

Sedimentary association of alternated mudstones and tight sandstones in China’s oil and gas bearing basins and its natural gas accumulation

Cited by 47 publications

References 17 publications

Facies controls on the distribution of diagenetic alterations in fan delta deposits: a case study from the Lower Cretaceous sandstone, Chagan Sag, Inner Mongolia, China

Facies controls on the distribution of diagenetic alterations in fan delta deposits: a case study from the Lower Cretaceous sandstone, Chagan Sag, Inner Mongolia, China

Depositional and Diagenetic Controls on Pore Structure of Tight Gas Sandstone Reservoirs: Evidence from Lower Cretaceous Bashijiqike Formation in Kelasu Thrust Belts, Kuqa Depression in Tarim Basin of West China

Accumulation Mechanism of Complicated Deep Carbonate Reservoir in the Tazhong Area, Tarim Basin

Contact Info

Product

Resources

About