Prediction of porosity and gas saturation for deep-buried sandstone reservoirs from seismic data using an improved rock-physics model

Luo, Yaneng; Huang, Handong; Jakobsen, Morten; Yang, Yixin; Zhang, Jinwei; Cai, Yanjie

doi:10.1007/s11600-019-00274-6

Cited by 14 publications

(7 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increasing evidence shows that lithology, petrophysical properties, and rock mechanical properties are the key factors controlling fracture development (Chang, Wang, Shi, & Xu, 2019; Luo et al, 2019; Zhang et al, 2017). Different types of rocks have different compositions, structures, and diagenetic strengths, and these characteristics result in large differences in mechanical properties and certain differences in shear and tensile capabilities (Yin, Tian, & Wu, 2019; Yin, Xie, Wu, Liu, & Ding, 2019).…”

Section: Discussionmentioning

confidence: 99%

Characteristics, influencing factors, and prediction of fractures in weathered crust karst reservoirs: A case study of the Ordovician Majiagou Formation in the Daniudi Gas Field, Ordos Basin, China

Xie

Zhou

Zhang³

et al. 2020

Geological Journal

View full text Add to dashboard Cite

The study of fractures in karst reservoirs is a hot spot in the field of geosciences. In this article, we conducted a systematic study on the characteristics, influencing factors, and prediction methods of karst reservoir fractures of the Ordovician Majiagou Formation in the Daniudi Gas Field, China. Both weathering and tectonic fractures are mainly developed in the Ma 5 member of the Majiagou Formation. The former is categorized into surface weathering, steep wall tensile and karst collapse fractures, and the latter is made of tensile and shear fractures. The palaeo-temperatures of the fracture filling inclusions range from 90 to 140 C, peaking at 111-120 C, which are derived from oxygen isotopes of −7.9 to −17.5‰, with average −14.1‰ from the same filling inclusions. Integrations of regional tectonic activities, inclusion tests, and stable isotope analysis recognizes four formation periods of fractures since the Caledonian. The factors controlling the development degree of the karst reservoir fractures include lithology, petrophysical properties, rock layer thickness, structural deformation strength, and karst palaeomorphology. The buckling thin plate simulation results show a good positive correlation between the maximum principal stress and tensile fracture density. The same positive correlation is also observed between the shear stress and fracture density. The ancient karst landforms have strongly affected the distribution of weathering fractures. Surficial weathering fractures occur typically in the weathered residual monadnocks, while steep wall tension ruptures in areas near geomorphic steep ridges, and karst collapse fractures in karst residual monadnocks and karst pit areas.

show abstract

Section: Discussionmentioning

confidence: 99%

Characteristics, influencing factors, and prediction of fractures in weathered crust karst reservoirs: A case study of the Ordovician Majiagou Formation in the Daniudi Gas Field, Ordos Basin, China

Xie

Zhou

Zhang³

et al. 2020

Geological Journal

View full text Add to dashboard Cite

show abstract

“…When the rock is compressed by tectonic stress, it will bend in a certain direction (He et al, 2015;Luo et al, 2019). Tension fractures are formed in the parts above the neutral plane due to tensile stress.…”

Section: Structural Deformation Strengthmentioning

confidence: 99%

Development mode of reverse fault‐associated fractures in deep tight sandstones: A case study in Xinchang Gas Field, Sichuan Basin, China

et al. 2021

View full text Add to dashboard Cite

Evaluation of natural fractures is the key issue of the prediction of sweet spots in deep tight sandstones. In this article, taking the tight gas sandstone reservoir of the Xu 2 Member (second member of the Upper Triassic Xujiahe Formation) in Xinchang Gas Field, West Sichuan Depression as an example, we systematically studied the characteristics, formation periods, influencing factors, and developmental mode of fractures using testing results of cores, thin sections, rock mechanics, isotopes, fluid inclusions, and the structural curvature simulation method. The results show that the Xu 2 Member mainly develops vertical and high-angle fractures. The fractures are highly effective and mainly developed in medium-fine-grained sandstone. The secondary minerals in the fractures have multi-stage filling processes. The fluid inclusions are mainly gas-liquid two-phase brine inclusions (secondary inclusions), and with the same crystal, the temperature difference between the brine inclusion and the organic inclusion is 23.7 C. Carbon and oxygen stable isotope tests show that calcite has two mixing stages. In the end, the formation periods of the fractures in the Xu 2 Member were divided into five stages. The influencing factors of fractures in the Xu 2 Member include lithology, fault, layer thickness, and structural deformation. According to geomechanical analysis, we finally established the development mode of reverse fault-associated fractures in the Xu 2 Member.

show abstract

“…In fact, in the reservoir storage of tight sandstone reservoirs, there are certain differences in the distribution of pore throats in different pore-throat intervals (Ma, 2005;Jiang et al, 2017;Pang et al, 2019;Liu et al, 2020;Kang, 2021). Therefore, quantitatively characterizing the micro-scale heterogeneity of pore-throats in tight sandstone reservoirs is the key to accurately describing the influence of pore structures on fluid occurrence characteristics (Lei et al, 2012;Sun et al, 2014;Li et al, 2019;Luo et al, 2019;Ren et al, 2019;Liu J et al, 2022). Pore-throat heterogeneity has a significant effect on tight reservoir permeability.…”

Section: Introductionmentioning

confidence: 99%

Micro-Scale Pore-Throat Heterogeneity of Tight Oil Sandstone Reservoirs and Its Influence on Fluid Occurrence State

et al. 2022

View full text Add to dashboard Cite

Quantitatively characterizing the micro-scale heterogeneity of pore throats in tight sandstone reservoirs is the key to accurately describing the influence of pore structures on fluid occurrence characteristics. In this study, taking the Chang 6 Member of the Yanchang Formation in the Huaqing area of the Ordos Basin as an example, the pore-throat heterogeneity of tight sandstone reservoirs and its influence on the fluid occurrence state have been systematically studied using cast thin section, scanning electron microscope, X-ray diffraction, constant velocity mercury intrusion, and nuclear magnetic resonance tests. The main types of pores developed in the target layer were intergranular pores, followed by feldspar dissolution pores. The radius distribution of the intergranular pores is between 5.0 and 210 μm, with an average value of 50.27 μm. In addition, the pore combination types with the best petrophysical properties are the intergranular pore type, the intergranular-dissolution pore type, and the dissolution-intergranular pore type; the average permeability and porosity are 0.62 mD, 0.40 mD, 0.44 mD, and 12.0, 12.3, 12.3%, respectively. The target sandstones contain four typical T2 relaxation time types. The large-pore-fine-throat combination reservoir has the best petrophysical properties. The larger the pore-throat uniformity value, the more uniform the pore-throat radius, and the greater the reservoir permeability. Therefore, the uniformity of throat development controls the seepage capacity of the tight reservoirs. The movable fluid saturation of different pore types has obvious differences. The movable fluid saturations at the 0.1 and 0.5 μm pore diameters of the macro-pore-fine-throat and macro-pore-micro-throat reservoirs both show an obvious inflection point, and the movable water saturation is higher with a larger throat radius.

show abstract

Prediction of porosity and gas saturation for deep-buried sandstone reservoirs from seismic data using an improved rock-physics model

Cited by 14 publications

References 49 publications

Characteristics, influencing factors, and prediction of fractures in weathered crust karst reservoirs: A case study of the Ordovician Majiagou Formation in the Daniudi Gas Field, Ordos Basin, China

Characteristics, influencing factors, and prediction of fractures in weathered crust karst reservoirs: A case study of the Ordovician Majiagou Formation in the Daniudi Gas Field, Ordos Basin, China

Development mode of reverse fault‐associated fractures in deep tight sandstones: A case study in Xinchang Gas Field, Sichuan Basin, China

Micro-Scale Pore-Throat Heterogeneity of Tight Oil Sandstone Reservoirs and Its Influence on Fluid Occurrence State

Contact Info

Product

Resources

About