National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields

Fengcheng, China

National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields

Fengcheng, China

Time filter

Source Type

Hui X.,China National Petroleum Corporation | Hui X.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Chu M.-J.,China National Petroleum Corporation | Chu M.-J.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields
Natural Gas Geoscience | Year: 2016

As an important large intracontinental depression sedimentary basin in China, the Ordos Basin has produced quantity of crude oil from Yanchang Formation.Due to the prospective drilling, more and more interests have been paid to the Chang 9 interval of Yanchang Formation in central Ordos Basin in the last few years.Despite of its optimum oil production, there are two types of Chang 9 sandstone reservoirs with distinct variation of sedimentary properties in western or eastern field.The three aspects of sandstone characteristics including mineral components, sedimentary facies, and sandstone distribution features are compared to demonstrate differences of features respectively in western or eastern fields in this paper.The west field is mostly occupied by those sandstones with following characteristics: Large thickness, predominant sands, and vertically continuous distribution.Correspondingly, those sandstones in the eastern field have some characteristics as following: Small thickness, more barrier mud intervals, and relative isolated distribution of sandstones.The variation mechanism is evaluated by conducting factors of sedimentary environment, flowing energy, and channel stability.They are prevailed by the braided river delta environment in the west field, which contrasts to the meandering river delta setting in the east field.The former type of reservoir, which defined sandstones as “high-energy, continuous, stable-course” in this paper, is dominated by shorter transportation, more powerful hydrodynamic energy, steeper slope of lake bottom bed, and more immobile river channel courses through geological sediment period, compared to the latter defined as “low-energy, intermittent, mobile-course” in this paper, of which sandstone bodies are controlled by longer transportation, less hydrodynamic power, gentle gradient slope, and frequent mobile stream courses. © 2016, Science Press. All right reserved.


Shi Y.,Petrochina | Shi Y.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Shi Z.,Petrochina | Zhang H.,Petrochina | And 2 more authors.
Xinan Shiyou Daxue Xuebao/Journal of Southwest Petroleum University | Year: 2012

Sulige Gas Field in Ordos Basin is the typical representation of tight sand gas reservoir of low permeability. According to the shapes of capillary pressure curves of core samples, based on self-organizing neural network, the pore structure automatic discrimination models and permeability interpretation models were established, which highly improved the permeability calculation precision. According to the research of reservoir conducting mechanism, we adopted the"three water model" (clay water, micro pore water and free water)for saturation interpretation model, which effectively improved the gas evaluation precision. Actual log data were processed with this method and its feasibility and veracity are validated by comparing the processed result with the core analysis result.


Yang H.,Petrochina | Yang H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Fu J.,Petrochina | Fu J.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | And 4 more authors.
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2012

Through lithological analysis of reservoirs, fluid inclusion test and simulation experiment, combined with geochemical, seismic, well logging and formation testing data, this paper studies the favorable geological conditions for tight gas accumulation in the Upper Paleozoic of the Ordos Basin, specifies the characteristics of tight gas reservoirs, and summarizes the key techniques for tight gas exploration and development. The gas source conditions of large area hydrocarbon generation and continuous hydrocarbon injection, widespread delta facies sandstone reservoirs, and the accumulation mode of short-distance migration facilitate the formation of the large-scale tight gas reservoirs in the Upper Paleozoic of the Ordos Basin. The Upper Paleozoic tight gas reservoirs in the Ordos Basin cover a large area and have many gas-bearing formations and multiple pressure systems. The tight reservoirs, which were formed before gas accumulation, are of high heterogeneity. Full digital seismic prediction technique for thin reservoirs, fine logging evaluation technique for tight gas reservoirs, and integrated supporting techniques for gas development provide technical support for further exploration and development.


Yang H.,Petrochina | Yang H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Fu J.,Petrochina | Fu J.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | And 7 more authors.
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2012

Through in-depth analysis of sedimentary source, lake basin shape and tectonic events as well as careful study of high quality source rocks, reservoir-forming force and history in the Huaqing area, Ordos Basin, the accumulation mode of large low-permeability lithologic oil regions in the middle of the lake basin was established. The Ordos Basin is a typical inland depressed basin during the depositional period of the Upper Triassic Yanchang Formation. Rich-nutrient lake-basin sediments are developed in the Chang-7 Member during the maximum flooding period. High-quality source rocks of the Chang-7 Member have the characteristics of high abundance of organic matter, strong ability of hydrocarbon generation and expulsion, and wide distribution in Huaqing in the central basin. Delta is developed extensively in the depositional period of Chang-6 Member. Influenced by rich provenance and the bottom shape of slope break belts, thick layers of reservoir sands originated from the delta front and gravity flow are developed in the Chang-6 Member in Huaqing, and the favorable sedimentary facies and diagenetic facies control the extensive low-permeability reservoirs. The Chang-6 low-permeability reservoirs and the Chang-7 high-quality source rocks have a good association and form an accumulation mode characterized by "hydrocarbon-generating pressurization, proximal migration and accumulation, large-area charging, and continuous oil layers".


Yang H.,Petrochina | Yang H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Deng X.,Petrochina | Deng X.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2013

A large area of deep-water sandstone was formed under the combined action of delta and gravity flow in the central Ordos Basin during the depositional period of the Ch6 and Ch7 oil-bearing formations of the Upper Triassic Yanchang Formation. According to U-Pb dating of zircons by the method of LA-ICP-MS, the ages of the tuff layers at the bottom and upper parts of Ch7 oil-bearing formation are 228.2± 2.0 Ma and 221.8±2.0 Ma, respectively. Based on the ages of the tuff layers, it is suggested that the gravity flow complexes at middle-upper Ch7 and lower-middle Ch6 oil-bearing formations were formed during 215-224 Ma. The depositional time of tuff and gravity flow is roughly the same as the time when tectonics are most active in the Qinling area, i.e. middle Indosinian period. The steadily widespread tuff at the bottom of the Ch7 oil-bearing formation and the extensive gravity flow sediments formed at early lake regression period are the direct outcomes of the tectonic event. Tuff layers are widely deposited at the bottom of Ch7 oil-bearing formation under the influence of the middle Indosinian tectonic events. Divided by the tuff layers, there is obvious difference in clastic composition between the lower and upper strata. The events control formation of large-area deep-water depressions, change of depositional system, migration of depositional center, and occurrence of gravity flow.


Yao J.,Petrochina | Yao J.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Deng X.,Petrochina | Deng X.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | And 8 more authors.
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2013

By comprehensive study of reservoir and source rock distribution, petrology and geochemistry, the tight oil and its exploration potential was analyzed in the Triassic Yanchang Formation, Ordos Basin. The Triassic Yanchang Formation is rich in low permeability reservoirs. The proved geological reserves of tight oil, with the permeability less than 2×10-3 μm2, is about two billion tons by now. The tight oil mainly occurs in tight sandstone reservoirs of Chang6-Chang8 oil-bearing members which are close to or interbedded with the oil shale layers, without long-distance migration. The large-scale gravity flow sandstone reservoirs of Chang7 and Chang6 oil-bearing members in the center of the lacustrine basin are particularly tight, with the permeability less than 0.3×10-3 μm2 in general. The tight oil in the Yanchang Formation features large scale in sand body complex, tight reservoir, complicated pore throat structure, high content of rigid components, abundant fractures and saturation, good crude property, low fluid pressure and low oil yield. The formation of large-scale superimposed tight oil reservoirs is controlled by the interbeded lithologic combination of extensive source rocks and reservoirs and the strong hydrocarbon generation and expulsion during geological history. This type of pools is an important potential resource for future oil exploration and development.


Yang H.,Petrochina | Yang H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Li S.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Li S.,Chengdu University of Technology | And 4 more authors.
Shiyou Xuebao/Acta Petrolei Sinica | Year: 2013

The Changqing Oilfield Company has extensively and efficiently developed reservoirs with ultra-low permeability between 0.3 mD and 1 mD. Based on the practice of petroleum exploration and development in Ordos Basin, the tight oil herein refers to the oil that accumulates in oil shale or interbedded tight sandstone reservoirs adjacent to source rocks and with surface-air permeability less than 0.3 mD. Generally, this accumulated oil has not yet experienced large-scale and long-distance migration, and thus its accumulation includes tight sandstone and tight shale oil reservoirs. The tight oil of Yanchang Formation mainly develops in a semi-deep to deep lake zone, typically in the oil shale and tight sandstone of Chang-7 interval and the tight sandstone of Chang-6 interval of the central lake. Tight oil in Ordos Basin is characterized by a wide distribution, superior conditions of source rocks, tight sandstone reservoirs, complex pore-throat structures, poor physical properties, high oil saturation, better oil properties and low pressure coefficient. Wide development of nano-sized pore-throat systems is one of the fundamental characteristics for the oil and gas continuous accumulation of tight oil reservoirs. Most of the connected pore-throat diameters of tight sandstone reservoirs in Yanchang Formation are greater than the critical pore-throat diameter, gratifying the need of oil and gas to migrate in tight reservoirs. Reservoirs of the tight oil in Yanchang Formation can be divided into 3 different types depending on the contact relationship between tight reservoirs and source rocks, i.e. compact massive sandstone reservoirs, sand-shale interbedded reservoirs and tight reservoirs in oil shale. Tight oil is widely distributed in Chang-6 and Chang-7 intervals of Yanchang Formation in Ordos Basin, and it is preliminarily forecasted that the total resources of tight oil in Ordos Basin are about 30×108t, of which the shale oil resource in Chang-7 interval exceeds 10×108t, while the tight sandstone oil resource in Chang-7 and Chang-6 intervals amounts to about 9×108t and 11×108t, respectively. Therefore, tight oil resources are the realistic oil replacement resources that can ensure Changqing Oilfield to achieve an annual output of 5000×108tons of oil equivalent and a long term stability of oil production.


Wenzheng Z.,Petrochina | Wenzheng Z.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Hua Y.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Hua Y.,Petrochina | And 5 more authors.
Petroleum Exploration and Development | Year: 2010

By optical microscopy and SEM-energy spectrometry, some phenomena that relate to lake-bottom hydrothermal activities, such as the presence of siliceous rocks, ankerite laminar deposits, evidence for marcasite brassil anhydrite symbiosis systems and authigenetic albite filling in early diagenetic fractures, have been discovered in the Chang 7 high-quality source beds of the Yanchang Formation, Ordos Basin. Various geochemical data of the Chang 7 high-quality source rocks testify further to the existence of lake-bottom hydrothermal activities, and they include abnormally abundant S2- content (on average 7.37%), Mo, Cu, U and Mn positive anomalies, high ratios of U to Th, the positive carbon isotope composition of crystalline ankerite (δ13C from 2.88 to 3.03‰), depleted oxygen isotope composition (δ18O PDB from -16.41 to -16.17‰), the enrichment of microelements like Cu and Mn, and isotopically enriched in 34S sulfur isotope compositions of strawberry-shaped pyrite (δ34S CDT from 2.37 to 5.90‰). In the early sedimentary period of the Chang 7, the activation of floor ruptures by violent regional structural activities was a dynamic factor that produced lake-bottom hydrothermal activities. The hydrothermal activities played an important role in accelerating the extensive development of the Chang 7 high-quality source rocks. © 2010 Research Institute of Petroleum Exploration & Development, PetroChina.


Yang H.,Petrochina | Yang H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Liu X.,Petrochina | Liu X.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2014

Based on practices of gas exploration in the Ordos Basin, this paper analyzes the controlling factors of large-scale accumulation conditions and distribution characteristics of coal-derived gas, and concludes the exploration progress of coal-derived gas according to the present exploration situations. There are 5.24×1012 m3 proven coal-derived gas reserves in the Ordos Basin. Twelve coal-derived gas fields have been found, mainly distributed in the Upper Paleozoic Carboniferous-Permian clastic rocks and Lower Paleozoic Ordovician marine carbonate reservoirs. Tight sandstone gas reservoirs are developed in the Upper Paleozoic. The widely covered hydrocarbon source of coal stacks each other with large-scale sandstone reservoirs, the reservoirs tightened firstly and natural gas accumulated later, and natural gas migrated shortly and accumulated in a large area. The Sulige large gas field has been found with proven coal-derived gas reserves of 3.49×1012 m3, and two large-scale reserve replacements have been determined in the eastern part of the basin and the Longdong area. Marine carbonate gas pools are developed in the Lower Paleozoic. The gas generated from the overlying coal source rocks migrated downward and accumulated in the Ordovician weathering crust karst and dolomite reservoirs. The Jingbian gas field has been found with proven coal-derived gas reserves of 7000×108 m3, meanwhile, several gas-rich regions have also been found.


Fu J.-H.,Petrochina | Fu J.-H.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | Li S.-X.,Petrochina | Li S.-X.,National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields | And 2 more authors.
Natural Gas Geoscience | Year: 2013

The Mesozoic Yanchang Formation mainly develops "low permeability, low pressure, low abundance" reservoirs, which is controlled by high quality source rocks and large sand body. In exploration practices, the traditional theoretical knowledge and exploration ideas made breakthrough, and the exploration theory in low permeability reservoirs also had constant innovation and improvement. The accumulation models, including meandering river delta, braided river delta, multi-layer and composite, the middle part of depression lake basin and tight oil, initiate a new situation of oil exploration. Guided by the meandering river delta accumulation theory, large oil-bearing region with geological reserves more than 1 billion tons have been found in the north Shanxi area. Based on the accumulation model of braided river deltas in southwest, monoblock oilfield has been discovered in eastern Gansu province, which has geological reserves more than 1 billion ton. According to the multiple layer compound accumulation model, more than 1. 5 billion tons geological reserves had been found in Jiyuan area. With the central lake accumulation model of inland depression basin, the exploration obtained a significant breakthrough in Huaqing area. With the advancement of tight oil geological research and technological breakthrough, new scaled reserve replacement area has been formed in the Ordos Basin. Based on the geological theory innovation, key technology breakthrough, systematic exploration and development implementation, and development mode change, it enhanced the integrated exploration benefit of "three low" oil and gas fields, solid the resource foundation of the rapid development of low permeability oil and gas fields, and achieved huge economic and social benefits.

Loading National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields collaborators
Loading National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields collaborators