Development modes of Triassic Yanchang Formation Chang 7 Member tight oil in Ordos Basin, NW China

Li, Zhongxing; Qu, Xuefeng; Liu, Wantao; Lei, Qihong; Sun, Hong; He, Yiqian

doi:10.1016/s1876-3804(15)30011-2

Cited by 64 publications

(23 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where G i is the shape factor of the irreducible water block (dimensionless), V w is the volume (μm 3 ), and S w is the surface area of the irreducible water block (μm 2 ). The shape factor represents the degree of sphericity of an object.…”

Section: Microoccurrence Of Irreduciblementioning

confidence: 99%

“…where S Swi ′ is the saturation of irreducible water in either the pore or the throat (%), V w is the irreducible water volume confined in a given pore or throat (μm 3 ), and V p−t is the pore or throat volume (μm 3 ). …”

Section: Microoccurrence Of Irreduciblementioning

confidence: 99%

“…Theory and practice have proved that water flooding is the most economical technology to replenish formation energy and enhance oil recovery (EOR) in low-permeability reservoirs [3]. During the water flooding, many geological factors determine the efficiency of water drives, such as rock permeability, porethroat structure, irreducible water saturation, and crude oil viscosity [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Visual and Quantitative Study of the Microoccurrence of Irreducible Water at the Pore and Throat System in a Low-Permeability Sandstone Reservoir by Using Microcomputerized Tomography

Huang

Khan

et al. 2018

Geofluids

View full text Add to dashboard Cite

The microflow equipment monitored with micro X-ray computerized tomography (CT) is employed to investigate the microoccurrence of the irreducible water in a low-permeability sandstone core. By means of image segmentation and the threedimensional (3D) image reconstruction technique, the visual microdistribution characteristics of irreducible water in twodimensional (2D) slices and the 3D pore-throat system are quantitatively evaluated. Some interesting findings are list as below. Firstly, due to the variant micro geometric structures of the pore-throat systems, specific core slices showed significantly different irreducible water saturation even though these slices had same areal porosity. Secondly, due to the influence of capillary trapping and the existence of oil-wetting clay (main chlorite), the irreducible water saturation in the throat system (64%) is much larger than that in the pore system (36%). Furthermore, the wetting phase (irreducible water) did not spread all over the surface of the pore-throat network which caused a much more complicated oil-water two-phase interface. Thirdly, in micro scale, the main irreducible water occurrence mode in the pore system is much different from that in the throat system. In the pore system, the irreducible water principally existed in the corner of the pores which are linked through a water film. While in the throat system, the irreducible water occurrence is dominated by the water film. However, 25.5% of the throats are blocked by the irreducible water which cut off the crude oil drainage channels.

show abstract

Section: Microoccurrence Of Irreduciblementioning

confidence: 99%

Section: Microoccurrence Of Irreduciblementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Visual and Quantitative Study of the Microoccurrence of Irreducible Water at the Pore and Throat System in a Low-Permeability Sandstone Reservoir by Using Microcomputerized Tomography

Huang

Khan

et al. 2018

Geofluids

View full text Add to dashboard Cite

show abstract

“…A large number of cracks occurs after reservoir volume fracturing [15][16][17][18], and waterflood development often results in a rapid outlet of water from the oil wells [19]. Therefore, the current volume transformation is mainly based on natural energy development [20]. The initial oil production using this process is high, but it decreases rapidly, which leads to low accumulative oil production and poor economic performance [21].…”

Section: Introductionmentioning

confidence: 99%

“…In fractured reservoirs, CO 2 may directly flow from injectors to producers through fractures without sweeping through the matrix, thereby reducing the sweep efficiency [34]. Given the problems arising in the development of tight oil reservoirs, waterflooding huff-n-puff has received renewed attention because of its economy and effectiveness [20]. Waterflooding huff-n-puff is suitable for well groups with low production and low formation energy.…”

Section: Introductionmentioning

confidence: 99%

Waterflooding Huff-n-puff in Tight Oil Cores Using Online Nuclear Magnetic Resonance

et al. 2018

View full text Add to dashboard Cite

Given the difficulty in developing waterflooding in tight oil reservoirs, using waterflooding huff-n-puff is an effective method to improve oil recovery. Online nuclear magnetic resonance (NMR) can detect the change in internal oil and water during the core displacement process, and magnetic resonance imaging (MRI) in real time. To improve the tight oil reservoir development effectiveness, cores with different permeability were selected for a waterflooding huff-n-puff experiment. Combined with online NMR equipment, the fluid saturation, recovery rate, and residual oil distribution were studied. The experiments showed that, for tight oil cores, more than 80% of the pores were sub-micro-and micro-nanopores. More than 77.8% of crude oil existed in the sub-micro-and micropores, and movable fluids mainly existed in the micropores with a radius larger than 1 µm. The NMR data and the MRI images both demonstrated that the recovery ratio of waterflooding after waterflooding huff-n-puff was higher than that of conventional waterflooding, and, therefore, residual oil was lower. Choosing two cycles' of waterflooding, huff-n-puff was more suitable for tight oil reservoir development. The production of crude oil increased by 22.2% in the field pilot test, which preliminarily proved that waterflooding huff-n-puff was suitable for tight oil reservoirs.

show abstract

Paleogeotemperature and maturity evolutionary history of the source rocks in the Ordos Basin

Ren

et al. 2017

Geological Journal

View full text Add to dashboard Cite

Tectonothermal evolution has an important control on maturity and hydrocarbon‐generation of source rocks. On the basis of analysis of the present‐day geothermal gradient, rock thermophysical parameters and heat flow, the thickness contour and vitrinite reflectance can be identified, and the distribution of thermal anomaly was discussed. The paleogeotemperature and paleogeothermal gradients are calculated after the recovery of the erosional thickness. With the theory of the recovering of the superposed and modified sedimentary basin, the evolutionary history since the end of Triassic, the end of Jurassic, the Late Early Cretaceous is presented for two sets of source rocks recovered in various perspectives of plans, cross‐sections, important wells, and typical areas. The impact of tectonothermal evolution on the maturity and hydrocarbon‐generation history of the source rocks is discussed. The paleogeothermal gradient (4.0 °C/100 m on average) is higher than the present one (2.9 °C/100 m on average). With the slightly continuous increase since the Late Paleozoic, the paleogeotemperature of the Ordos Basin reached its maximum in Late Early Cretaceous and decreased continuously from then on. The paleogeotemperature and maturity of the source rocks continuously increased before Late Early Cretaceous. The tectonothermal event during Late Jurassic to Early Cretaceous controlled the source rocks with the high temperature and maturity in the Wuqi‐Qingyang‐Fuxian. The temperature decreased, and the maturity hardly changed after the Late Cretaceous. The source rocks of the Shanxi Formation reached maturity, high maturity and over‐maturity at the Late Triassic, the Late Jurassic, and the Early Cretaceous, respectively. The source rocks of the Yanchang Formation reached low maturity and maturity sequentially all in the Early Cretaceous.

show abstract

Development modes of Triassic Yanchang Formation Chang 7 Member tight oil in Ordos Basin, NW China

Cited by 64 publications

References 2 publications

The Visual and Quantitative Study of the Microoccurrence of Irreducible Water at the Pore and Throat System in a Low-Permeability Sandstone Reservoir by Using Microcomputerized Tomography

The Visual and Quantitative Study of the Microoccurrence of Irreducible Water at the Pore and Throat System in a Low-Permeability Sandstone Reservoir by Using Microcomputerized Tomography

Waterflooding Huff-n-puff in Tight Oil Cores Using Online Nuclear Magnetic Resonance

Paleogeotemperature and maturity evolutionary history of the source rocks in the Ordos Basin

Contact Info

Product

Resources

About