Marine and Petroleum Geology最新文献_第5页

Multi-component model simulation of the formation mechanism of a retrograde lowstand wedge during slow sea-level fall

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2025-01-03 DOI: 10.1016/j.marpetgeo.2024.107281

Haoyuan Lv , Guoqiang Xu

In many sequence-stratigraphic models, the slow sea-level fall stage corresponds to the development of retrograde lowstand slope fans. However, a unified and clear explanation for whether sediment existed at the shelf edge and the resulting sediment stacking pattern during this stage is lacking. Based on observational data and a pre-existing prototype sequence model established according to the data, we found that during the slow sea-level fall stage, a retrograde lowstand wedge can develop at the shelf edge. To explain this retrograde lowstand wedge and clarify its formation mechanism during slow sea-level fall, this study simulated the stratigraphic stacking pattern of a prototype sequence in a passive continental margin basin in the north of the South China Sea using a two-dimensional multi-component model. We then simulated the distribution of accommodation during six stages in a 3rd-order cycle and described the structural changes in the stratigraphic units over 100,000 years. The simulation results indicated that based on the average thermal subsidence of the shelf, differential thermal subsidence and compaction subsidence of sediment lead to the generation of more accommodation at the shelf edge during the slow sea-level fall stage. Moreover, this leads to the retention of more accommodation at the top of the forced regressive wedge before the development of the retrograde wedge (in which compaction plays an important role). Influenced by this, the distribution of accommodation and sediment migrates landward, leading to the development of the retrograde lowstand wedge. The results of this study elucidate the formation mechanism of retrograde lowstand wedges and improve the theory of sequence stratigraphy.

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引用次数: 0

First application of high-resolution X-ray computed tomography to quantify the fossil record of foraminifera: The Nicola bed, Monte San Nicola, Sicily; type area for the Quaternary System

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2025-01-03 DOI: 10.1016/j.marpetgeo.2024.107283

Wiesława Radmacher , Martin J. Head , Grzegorz P. Kaczmarczyk , Mateusz Mikołajczak , Adam Włodek , Anna Spadło , Daniel Wałach , Alfred Uchman , Antonio Caruso

The distinctive microlaminated Nicola bed marks the base of the Quaternary System at the type locality of Monte San Nicola in southern Sicily. We have analysed a sediment block that traverses the Nicola bed at the Mandorlo section located ∼400 m WNW of the GSSP. Primary sedimentological and ichnofabric analysis of the polished surface combined with X-ray computed tomography (CT) reveals changes in dissolved bottom water oxygen levels before, during and after deposition of the Nicola bed, beginning with a progressive but rapid transition to anoxia at its onset. A more gradual recovery to oxygenated conditions followed Nicola bed deposition. Planktonic foraminifera are recognised by X-ray CT as either empty or infilled near-spherical voids, and the individual volume (≈size) is estimated for each test in addition to its position in the sediment block. Pronounced foraminiferal abundance peaks through the Nicola bed, with a frequency of hundreds of years, suggest (quasi-)cyclical changes in the mixed layer of the water column, thereby implicating either high-frequency oscillations within the climate system or the long-term modulation of solar cycles. This is the first study to explore the distribution of foraminiferal tests through a sediment block using X-ray CT, revealing its potential as an inexpensive non-destructive method for the quantitative study of microfossils at extremely high stratigraphic resolution.

{"title":"First application of high-resolution X-ray computed tomography to quantify the fossil record of foraminifera: The Nicola bed, Monte San Nicola, Sicily; type area for the Quaternary System","authors":"Wiesława Radmacher , Martin J. Head , Grzegorz P. Kaczmarczyk , Mateusz Mikołajczak , Adam Włodek , Anna Spadło , Daniel Wałach , Alfred Uchman , Antonio Caruso","doi":"10.1016/j.marpetgeo.2024.107283","DOIUrl":"10.1016/j.marpetgeo.2024.107283","url":null,"abstract":"<div><div>The distinctive microlaminated Nicola bed marks the base of the Quaternary System at the type locality of Monte San Nicola in southern Sicily. We have analysed a sediment block that traverses the Nicola bed at the Mandorlo section located ∼400 m WNW of the GSSP. Primary sedimentological and ichnofabric analysis of the polished surface combined with X-ray computed tomography (CT) reveals changes in dissolved bottom water oxygen levels before, during and after deposition of the Nicola bed, beginning with a progressive but rapid transition to anoxia at its onset. A more gradual recovery to oxygenated conditions followed Nicola bed deposition. Planktonic foraminifera are recognised by X-ray CT as either empty or infilled near-spherical voids, and the individual volume (≈size) is estimated for each test in addition to its position in the sediment block. Pronounced foraminiferal abundance peaks through the Nicola bed, with a frequency of hundreds of years, suggest (quasi-)cyclical changes in the mixed layer of the water column, thereby implicating either high-frequency oscillations within the climate system or the long-term modulation of solar cycles. This is the first study to explore the distribution of foraminiferal tests through a sediment block using X-ray CT, revealing its potential as an inexpensive non-destructive method for the quantitative study of microfossils at extremely high stratigraphic resolution.</div></div>","PeriodicalId":18189,"journal":{"name":"Marine and Petroleum Geology","volume":"174 ","pages":"Article 107283"},"PeriodicalIF":3.7,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143178262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Corrigendum to “The latest activity of the slope fault zone (Pearl River Mouth) in northern South China Sea and implications for earthquake hazard assessments” [166 (2024) 106937]

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2025-01-01 DOI: 10.1016/j.marpetgeo.2024.107209

Liangwei Lv , Zhigang Li , Dawei Wang , Weitao Wang , Xiangming Dai , Fanchang Zeng , Linlin Li , Hao Liang , Gege Hui , Weiwang Long , Peizhen Zhang

引用次数: 0

Oil–reservoir correlation: Unravelling the producing reservoir for the sulfur-rich Qianjiang shale oil play

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2025-01-01 DOI: 10.1016/j.marpetgeo.2024.107176

Yuanjia Han , Dongqi An , Shiqiang Wu , Furong Wang , Xiaowen Guo , Zhiliang He

The hypersaline Qianjiang shale oil play represents a promising yet challenging target for exploration due to its multiple stacked shale-carbonate layers, which complicate the identification of the most viable extraction sites. Additionally, the oil accumulated in these layers is immature to low-mature and considerably high in sulphur content. To trace the shale zones after fracturing, a newly developed oil-reservoir correlation method employing Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was utilised. This method proved effective in distinguishing between the acidic nitrogen-, sulphur-, and oxygen-containing (NSO) compounds identified by the negative mode of electrospray ionisation FT-ICR MS and the less polar NSO compounds and aromatic hydrocarbons detected by positive ion atmospheric pressure photoionisation FT-ICR MS. These compounds facilitated the deconvolution of oils produced from mixed layers in the hypersaline Qianjiang shale play. The zones of oil production identified through this method corresponded well with shale reservoirs previously characterised by anomalously high oil saturation index values (OSI >400 mg/g TOC) and a preferential enrichment of saturated hydrocarbons. A detailed analysis of C_31-35 homohopane distributions in shale extracts and crude oil corroborated these findings. The variability in the producibility of NSO compounds and aromatic hydrocarbons was examined based on functional group, degree of aromatisation, and molecular weight. During production, sulphur- and nitrogen-containing compounds predominantly migrated into the produced oil, whereas oxygen-containing compounds were less affected. Nonetheless, determining the production partitioning of aromatic hydrocarbons remains challenging; if present, it may be obscured by the commingled production effects from multiple layers.

{"title":"Oil–reservoir correlation: Unravelling the producing reservoir for the sulfur-rich Qianjiang shale oil play","authors":"Yuanjia Han , Dongqi An , Shiqiang Wu , Furong Wang , Xiaowen Guo , Zhiliang He","doi":"10.1016/j.marpetgeo.2024.107176","DOIUrl":"10.1016/j.marpetgeo.2024.107176","url":null,"abstract":"<div><div>The hypersaline Qianjiang shale oil play represents a promising yet challenging target for exploration due to its multiple stacked shale-carbonate layers, which complicate the identification of the most viable extraction sites. Additionally, the oil accumulated in these layers is immature to low-mature and considerably high in sulphur content. To trace the shale zones after fracturing, a newly developed oil-reservoir correlation method employing Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was utilised. This method proved effective in distinguishing between the acidic nitrogen-, sulphur-, and oxygen-containing (NSO) compounds identified by the negative mode of electrospray ionisation FT-ICR MS and the less polar NSO compounds and aromatic hydrocarbons detected by positive ion atmospheric pressure photoionisation FT-ICR MS. These compounds facilitated the deconvolution of oils produced from mixed layers in the hypersaline Qianjiang shale play. The zones of oil production identified through this method corresponded well with shale reservoirs previously characterised by anomalously high oil saturation index values (OSI >400 mg/g TOC) and a preferential enrichment of saturated hydrocarbons. A detailed analysis of C<sub>31-35</sub> homohopane distributions in shale extracts and crude oil corroborated these findings. The variability in the producibility of NSO compounds and aromatic hydrocarbons was examined based on functional group, degree of aromatisation, and molecular weight. During production, sulphur- and nitrogen-containing compounds predominantly migrated into the produced oil, whereas oxygen-containing compounds were less affected. Nonetheless, determining the production partitioning of aromatic hydrocarbons remains challenging; if present, it may be obscured by the commingled production effects from multiple layers.</div></div>","PeriodicalId":18189,"journal":{"name":"Marine and Petroleum Geology","volume":"171 ","pages":"Article 107176"},"PeriodicalIF":3.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Corrigendum to “Mapping the resistivity structure of Walker Ridge 313 in the Gulf of Mexico using the marine CSEM method” [Mar. Petrol. Geol. 88 (2017), 1013–1031]

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2025-01-01 DOI: 10.1016/j.marpetgeo.2024.107200

Karen Weitemeyer , Steven Constable , Dianna Shelander , Seth Haines

引用次数: 0

A novel method for automatic quantification of different pore types in shale based on SEM-EDS calibration

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2024-12-31 DOI: 10.1016/j.marpetgeo.2024.107278

Zhentao Dong , Shansi Tian , Haitao Xue , Shuangfang Lu , Bo Liu , Valentina Erastova , Guohui Chen , Yuying Zhang

Pore type is a crucial consideration in the quantification of shale pores. Convolutional Neural Networks (CNNs) are widely used for identifying pore types in shale, but it is hampered by feature extraction bias, difficult data labeling, and poor generalization ability. Compared to secondary electron (SE) images, mineral distribution maps have low resolutions that pose a significant obstacle to pore type identification. This paper presents a method for identifying and quantifying pore types based on pore-matrix contact relationships. Organic matter, organic pores, and inorganic pores are extracted from SE images using the edge-threshold automatic processing (ETAP) method. Next, the labeled watershed algorithm is used to improve the low-resolution mineral distribution map to the SE image level. The high-resolution mineral distribution map is then combined with pore extraction images, permitting the identification of pore types. Finally, pore size, surface porosity, generalized fractal dimension, and contact angle are calculated for each pore type. We used this new method to identify pores in images of the Longmaxi, Qiongzhusi, and Qingshankou shale. We found that high-resolution mineral distribution maps significantly enhance pore identification accuracy. The Longmaxi Formation clay-rich shale is dominated by organic pores (over 60%), while the Qiongzhusi Formation siliceous shale is characterized by intergranular pores and fractures (fractures contributing 30%). In the Qingshankou Formation clay-rich shale, clay pores (35%) and cracks dominate, whereas the Qingshankou Formation siliceous shale is primarily composed of intergranular pores (17%) and cracks (30%), with distinct pore size distributions across these lithofacies. There is a significant difference in the wettability of the matrix and pores of the Longmaxi shale, primarily due to the dominant influence of organic matter on the pore surfaces.

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引用次数: 0

Depositional evolution and sedimentary response to sea level changes of the lower Cambrian carbonate platform of the Wusonggeer Formation, Tarim Basin, northwest China

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2024-12-30 DOI: 10.1016/j.marpetgeo.2024.107269

Xuqiao Wu , Changsong Lin , Wenfang Yuan , Hao Li , Xianzhang Yang , Fan Xu , Manli Zhang , Xiangyu Liu

The Wusonggeer Formation of the Cambrian Series 2 is one of the important carbonate oil/gas bearing intervals in the Tarim Basin. It recorded significant paleoclimatic conditions and history of sea-level variation and has long been a popular research issue in the region. Based on drilling data and thin sections from core wells, 18 microfacies (Mf1–Mf18) and 11 microfacies associations (MA1–MA11) of the Formation are identified, and the main depositional facies include mixed tidal flat, evaporated platform, restricted platform, semi-restricted platform, platform margin, and slope-shelf deposits. According to unconformity contacts such as toplap and onlap, lithofacies transition and karst interfaces, the Wusonggeer Formation comprises a composite sequence (WCS1) and three shallowing-upward third-order sequences (WSQ1–WSQ3). The highstand systems tracts (HST) dominate each sequence and consist mainly of evaporated lagoon deposits (MA3), reef–shoal complexes and shoal deposits (MA8), while the transgressive systems tracts (TST) are predominately composed of intershoal deposits (MA9) and restricted tidal flat deposits (MA7). The depositional architecture from WSQ1 to WSQ3 evolved from restricted to evaporated carbonate platforms, revealing three depositional stages of carbonate platform in gradual arid and warm climatic background, including semi-restricted rimless platform in a relatively humid climate (WSQ1), restricted weak-rimmed platform in a semi-arid climate (WSQ2), and evaporated weak-rimmed platform in an arid climate (WSQ3). The salinity changes of the seawater seem to be consistent with the relative sea-level change indicated by the stacking pattern of facies associations and this may suggest that the depositional cycles of the platform were mainly constrained by the synergistic processed of climate and sea level change. WSQ2 marks a key turning period from a relatively humid climatic condition to a dry and hot climate is suggested to be the result of the global climate change during the late Cambrian Series 2.

{"title":"Depositional evolution and sedimentary response to sea level changes of the lower Cambrian carbonate platform of the Wusonggeer Formation, Tarim Basin, northwest China","authors":"Xuqiao Wu , Changsong Lin , Wenfang Yuan , Hao Li , Xianzhang Yang , Fan Xu , Manli Zhang , Xiangyu Liu","doi":"10.1016/j.marpetgeo.2024.107269","DOIUrl":"10.1016/j.marpetgeo.2024.107269","url":null,"abstract":"<div><div>The Wusonggeer Formation of the Cambrian Series 2 is one of the important carbonate oil/gas bearing intervals in the Tarim Basin. It recorded significant paleoclimatic conditions and history of sea-level variation and has long been a popular research issue in the region. Based on drilling data and thin sections from core wells, 18 microfacies (Mf1–Mf18) and 11 microfacies associations (MA1–MA11) of the Formation are identified, and the main depositional facies include mixed tidal flat, evaporated platform, restricted platform, semi-restricted platform, platform margin, and slope-shelf deposits. According to unconformity contacts such as toplap and onlap, lithofacies transition and karst interfaces, the Wusonggeer Formation comprises a composite sequence (WCS1) and three shallowing-upward third-order sequences (WSQ1–WSQ3). The highstand systems tracts (HST) dominate each sequence and consist mainly of evaporated lagoon deposits (MA3), reef–shoal complexes and shoal deposits (MA8), while the transgressive systems tracts (TST) are predominately composed of intershoal deposits (MA9) and restricted tidal flat deposits (MA7). The depositional architecture from WSQ1 to WSQ3 evolved from restricted to evaporated carbonate platforms, revealing three depositional stages of carbonate platform in gradual arid and warm climatic background, including semi-restricted rimless platform in a relatively humid climate (WSQ1), restricted weak-rimmed platform in a semi-arid climate (WSQ2), and evaporated weak-rimmed platform in an arid climate (WSQ3). The salinity changes of the seawater seem to be consistent with the relative sea-level change indicated by the stacking pattern of facies associations and this may suggest that the depositional cycles of the platform were mainly constrained by the synergistic processed of climate and sea level change. WSQ2 marks a key turning period from a relatively humid climatic condition to a dry and hot climate is suggested to be the result of the global climate change during the late Cambrian Series 2.</div></div>","PeriodicalId":18189,"journal":{"name":"Marine and Petroleum Geology","volume":"173 ","pages":"Article 107269"},"PeriodicalIF":3.7,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

How bedding-parallel fractures affect fluid activity in a relatively closed lacustrine shales system: Evidence from calcite veins

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2024-12-27 DOI: 10.1016/j.marpetgeo.2024.107276

Zilong Li , Kelai Xi , Xiaobing Niu , Xiujuan Wang , Wenzhong Ma , Xiao Hui , Jiangyan Liu , Changyu Fan , Miruo Lin , Keyu Liu , Yingchang Cao

The redistribution of materials and elements in rocks, the transport of hydrocarbon, the metamorphic reaction of lithosphere rheology, and the sequestration of greenhouse gases all depend on fluid activity. In a relatively closed lacustrine shales system that has experienced strong physical and chemical compaction, there has been not fully understood how fluid activity channels are generated due to few records of fluid activity. To investigate these processes, we present the petrography, isotope geochemistry, cathodoluminescence, fluid inclusions, electron probe microanalysis, and rare earth elements of bedding-parallel calcite veins (BPCVs) found in the lacustrine organic-rich shales of the Chang 7₃ sub-member of the Yanchang Formation in Ordos Basin. Our investigations show that the opening of bedding-parallel fractures (BPFs) in a relatively closed lacustrine shales system can significantly promote fluid flow and fluid-rock interactions. Three distinct stages of BPCVs can been identified: Cal-1, Cal-2, and Cal-3. Cal-1 was the result of active fracturing of host rocks under the crystallization force in the process of in-situ recrystallization after pressure dissolution of inorganic micrite carbonate minerals. The δ¹³C values of Cal-2 is consistent with the values of organic carbon generated by thermal decarboxylation, indicating that the BPFs may be opened under the hydrocarbon generation overpressure and promote hydrocarbon expulsion. Cal-3 is associated with the micro-thrust fault structure, δEu value is a positive anomaly, which is significantly different from host rocks, reflecting that the BPFs opened under the horizontal tectonic compression and then acted as flow channels for organic fluid and deep hydrothermal fluid. This study emphasizes that the opening of BPFs in a relatively closed lacustrine shales system has obvious multi-stage characteristics, which significantly promotes fluid flow and material exchange, affects the diagenetic evolution and hydrocarbon expulsion, and is an important response to the multi-scale and episodic fluid activity in sedimentary basins.

{"title":"How bedding-parallel fractures affect fluid activity in a relatively closed lacustrine shales system: Evidence from calcite veins","authors":"Zilong Li , Kelai Xi , Xiaobing Niu , Xiujuan Wang , Wenzhong Ma , Xiao Hui , Jiangyan Liu , Changyu Fan , Miruo Lin , Keyu Liu , Yingchang Cao","doi":"10.1016/j.marpetgeo.2024.107276","DOIUrl":"10.1016/j.marpetgeo.2024.107276","url":null,"abstract":"<div><div>The redistribution of materials and elements in rocks, the transport of hydrocarbon, the metamorphic reaction of lithosphere rheology, and the sequestration of greenhouse gases all depend on fluid activity. In a relatively closed lacustrine shales system that has experienced strong physical and chemical compaction, there has been not fully understood how fluid activity channels are generated due to few records of fluid activity. To investigate these processes, we present the petrography, isotope geochemistry, cathodoluminescence, fluid inclusions, electron probe microanalysis, and rare earth elements of bedding-parallel calcite veins (BPCVs) found in the lacustrine organic-rich shales of the Chang 7<sub>3</sub> sub-member of the Yanchang Formation in Ordos Basin. Our investigations show that the opening of bedding-parallel fractures (BPFs) in a relatively closed lacustrine shales system can significantly promote fluid flow and fluid-rock interactions. Three distinct stages of BPCVs can been identified: Cal-1, Cal-2, and Cal-3. Cal-1 was the result of active fracturing of host rocks under the crystallization force in the process of in-situ recrystallization after pressure dissolution of inorganic micrite carbonate minerals. The δ<sup>13</sup>C values of Cal-2 is consistent with the values of organic carbon generated by thermal decarboxylation, indicating that the BPFs may be opened under the hydrocarbon generation overpressure and promote hydrocarbon expulsion. Cal-3 is associated with the micro-thrust fault structure, δEu value is a positive anomaly, which is significantly different from host rocks, reflecting that the BPFs opened under the horizontal tectonic compression and then acted as flow channels for organic fluid and deep hydrothermal fluid. This study emphasizes that the opening of BPFs in a relatively closed lacustrine shales system has obvious multi-stage characteristics, which significantly promotes fluid flow and material exchange, affects the diagenetic evolution and hydrocarbon expulsion, and is an important response to the multi-scale and episodic fluid activity in sedimentary basins.</div></div>","PeriodicalId":18189,"journal":{"name":"Marine and Petroleum Geology","volume":"173 ","pages":"Article 107276"},"PeriodicalIF":3.7,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143147825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating routine and novel methods for a comprehensive analysis of heterogeneity in Persian Gulf's Permian-Triassic carbonate reservoirs

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2024-12-27 DOI: 10.1016/j.marpetgeo.2024.107277

Adeleh Jamalian, Vahid Tavakoli

This study investigates the interplay between depositional environments and diagenetic processes in controlling the reservoir heterogeneity of Permian–Triassic carbonate platform of the Persian Gulf. Understanding this framework is crucial for identifying and characterizing reservoir heterogeneity at both micro and macro scales. A combined approach of integrated data (thin section analysis, petrophysical measurements, FMI and DT logs) used to evaluate reservoir heterogeneity of the upper Dalan and Kangan formations. Detailed analysis of sedimentary properties revealed a homoclinal ramp depositional environment, leading to minimal inherent heterogeneity within facies. Facies were subsequently classified into two main groups: mud-dominated and grain-dominated. Diagenetic processes, including dissolution, dolomitization, anhydritization, and cementation, further influenced these facies. This resulted in the creation of two distinct classes: mud-dominated facies (Class I) with low porosity and permeability, and grain-dominated facies (Class II) with high porosity and permeability. FMI log analysis highlighted the role of stylolites and conductive seams in shaping the heterogeneity within these two classes. Open stylolites in Class II have increased pore connectivity and enhanced permeability, while having minimal impact on Class I. Finally, core porosity data combined with the DT log enabled a more comprehensive assessment of pore types and their influence on reservoir heterogeneity within each class. DT logs identified two distinct facies groups. The first group exhibited high porosity and permeability with connected pores, representing grain-dominated facies. The second group showed low porosity and permeability with disconnected pores, representing mud-dominated facies. This approach provides valuable insights into the factors governing heterogeneity in carbonate reservoirs, offering a framework for improved reservoir characterization and development strategies.

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引用次数: 0

Response of source-to-sink patterns during the Mesozoic to tectonic setting in southwestern Tarim Basin: Insights from detrital zircon geochronology and morphology

IF 3.7 2区地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Marine and Petroleum Geology

Pub Date : 2024-12-22 DOI: 10.1016/j.marpetgeo.2024.107272

Junjian Li , Liqiang Zhang , Zuotao Wang , Yiming Yan , Cai Chen

Multiple Mesozoic tectonic movements in the southwestern Tarim Basin led to the change of accommodation space caused by tectonic setting switch, which resulted the process from source to sink being dominated by drainage systems. The source-to-sink pattern with structural features has complicated the distribution of the Mesozoic strata. Since all information is recorded in the associated basin infill, we conducted research on new samples from the Jurassic, Cretaceous, Permian that can provide limitations for the missing Triassic stratum. By analyzing the difference between the depositional age and the crystallization age of zircon grains, we confirmed the Jurassic extensional tectonic setting and the collisional tectonic setting of the Triassic and Cretaceous. By comparing the new detrital zircon geochronological data with the published data, a morphological classification of zircons applicable to complex transport processes was proposed, and the characteristics of provenance indicated by this classification were combined with new sedimentary and seismic stratigraphic evidence to establish two source-to-sink patterns, namely dominated by drainage basin under the Jurassic extensional setting and dominated by drainage channels under the Cretaceous collision setting. Under the Jurassic extensional setting, the debris mainly originated from the Tiekelike Uplift, and the subsidence of the hanging wall resulted in an increase in the accommodation space. The sedimentary system was small, and the distribution direction of isolated sedimentary centers in the sedimentary basin is parallel to the fault, which indicated that drainage basin which perpendicular to the direction of the provenance dominating, reducing the catchment area. Under the Cretaceous collision setting, the transportation of debris from the West Kunlun Orogenic Belt and the Tiekelike Uplift to the basin means that the catchment area increases and the role of drainage basin weakens. The overlapping sedimentary systems and changes in sedimentary facies indicate an increase in number and scale of drainage channels.

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引用次数: 0