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Collaborating Authors
China University of Petroleum Beijing
Adaptive Merging Migration
Liu, Lu (Aramco Research Center - Beijing) | Salim, Hussain (Saudi Aramco) | Chen, Ke (China University of Petroleum Beijing) | Zhao, Yang (China University of Petroleum Beijing)
Velocity errors and data noise are inevitable for seismic imaging of field datasets in current production; therefore, it is desirable to improve the seismic images as part of the migration process to mitigate the influence of such errors and noise. To address this, we have developed a new method of adaptive merging migration (AMM). This method can produce migrated sections of equal quality to conventional migration methods given a correct velocity model and noise-free data. Additionally, it can ameliorate the seismic image quality when applied with erroneous migration velocity models or noisy seismic data. AMM employs an efficient recursive Radon transform to generate multiple p-component images, representing migrated sections associated with different local plane slopes. It then adaptively merges the subsections from those p-component images that are less distorted by velocity errors or noise into the whole image. Such merging is implemented by computing adaptive weights followed by a selective stacking. We use three synthetic velocity models and one field dataset to evaluate the AMM performance on isolated Gaussian velocity errors, inaccurate smoothed velocities, velocity errors around high-contrast and short-wavelength interfaces, and noisy seismic data. Numerical tests conducted on both synthetic and field datasets validate that AMM can effectively improve the seismic image quality in the presence of different types of velocity errors and data noise.
- Geophysics > Seismic Surveying > Seismic Processing > Seismic Migration (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling > Seismic Inversion (0.46)
Dynamic Fracture Characterization Using Multiphase Rate Transient Analysis of Flowback and Production Data
Zhang, Zhengxin (China University of Petroleum Beijing) | Sun, Guoqing (Northeast Petroleum University) | Zhou, Xingze (PetroChina Changqing Oilfield Company) | Dang, Kaiyan (Shaanxi YanChang Petroleum Group Co., Ltd.) | Su, Xing (Pennsylvania State University)
Abstract This study presented a comprehensive method for characterizing reservoir properties and hydraulic fracture (HF) closure dynamics using the Rate Transient Analysis (RTA) of flowback and production data. The proposed method includes straight-line analysis (SLA), type-curve analysis (TCA), and model history matching (MHM), which are developed for scenarios of two-phase flow in fracture, stimulated reservoir volume (SRV), and NSRV domains. HF closure dynamics are characterized by two key parameters: pressure-dependent permeability and porosity controlled by fracture permeability-modulus and compressibility. The above techniques are combined into a generalized workflow to iteratively estimate the five parameters (four optional parameters and one fixed parameter) by reconciling data in different domains of time (single-phase water flow, two-phase flow, and hydrocarbon-dominated flow), analysis methods (SLA, TCA, MHM), and phases (water and hydrocarbon phase). We used flowback and production data from a shale gas well in the US to verify the practicability of the method. The analysis results of the field cases confirm the good performance of the newly developed comprehensive method and verify the accuracy in estimating the static fracture properties (initial fracture pore volume and permeability) and the HF dynamic parameters using the proposed generalized workflow. The accurate prediction of the decreasing fracture permeability and porosity, fracture permeability-modulus, and compressibility demonstrates the applicability of the workflow in quantifying HF dynamics. The field application results suggest a reduction of the fracture pore volume by 30%, and a reduction of the fracture permeability by 98% for shale gas well. Instead of a single analysis method for RTA, this paper proposed a comprehensive analysis method that includes SLA, TCA, and MHM. The interpretation results of the three analysis methods are mutually constrained, which can reduce the non-uniqueness problem of inversion. Compared with the others fracture characterization workflow that need fixed input and output parameters. This proposes general workflow not only completely characterizes the fracture closure dynamics but also can select the unknown parameters (to be determined) according to the actual scenarios of a well and the demands of reservoir engineers.
- Asia (1.00)
- North America > United States (0.89)
- North America > Canada > Alberta (0.28)
- Research Report > New Finding (0.34)
- Research Report > Experimental Study (0.34)
- Geology > Geological Subdiscipline > Geomechanics (0.70)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.56)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Pennsylvania > Appalachian Basin > Marcellus Shale Formation (0.99)
- (8 more...)
Pre-Drilling Prediction of 3D Geomechanical Parameters Based on Seismic Data: A Case Study of Tarim Oilfield
Zhou, Bo (PetroChina Tarim Oilfield Company) | Zhang, Xin (China University of Petroleum Beijing) | Zhao, Li (PetroChina Tarim Oilfield Company) | Zhou, Bao (PetroChina Tarim Oilfield Company) | Chen, Long (PetroChina Tarim Oilfield Company) | Lu, Yunhu (China University of Petroleum Beijing)
ABSTRACT A pre-drill prediction method of 3D geomechanical parameters based on seismic data is proposed. Firstly, the wave impedance parameters are predicted in the target area by the logging-constrained method, which mainly uses post-stack seismic data and logged data from drilled wells. The density and velocity data are obtained by separating the wave impedance data. Then, the density and velocity data are used as input to calculate 3D geomechanical parameters in the region, including elasticity parameters, strength parameters, and stress parameters. In particular, experimental data are used to correct the accuracy of the model. The results accurately reflect the geological complexity and non-homogeneity of the region by evaluating the elastic properties, mechanical properties, and stress magnitude of each point. This method can greatly improve the longitudinal resolution of the inversion results by fully exploiting a priori information from the logs and involving them in the seismic inversion process. Pre-drill parameters prediction of a complex field in the Tyuritag of the Tarim Basin is carried out. INTRODUCTION A growing number of oil and gas field development projects are facing the challenge of safe, rapid, and efficient development, such as offshore projects like Hibernia and the Gulf of Mexico in Canada, and onshore projects in tectonically active areas like the Cusiana field in Colombia and the Tarim Basin in China. However, as drilling depths continue to deepen, the geological environment encountered in oil and gas development is becoming increasingly complex. The difficulty of engineering problems related to geomechanics is also increasing. On the one hand, there are more and more complex accidents in various wells, such as well wall instability, well leakage, and sand production. Underground accidents seriously increase the time and cost of construction operations. It is estimated that at least 10% of the average well budget is used for unplanned operations due to wellbore instability (Sheng, 2006; Wei, 2012). On the other hand, the inaccuracy of geomechanical modeling makes geomechanics-related engineering measures unable to achieve the expected goals. In shale oil and gas development, about 30-50% of fracturing clusters do not contribute to product improvement. The root cause is poorly designed hydraulic fracturing strategies due to the lack of accurate geomechanical data (Zhang, 2018; Parshall, 2015).
- North America > United States (1.00)
- Asia > China > Xinjiang Uyghur Autonomous Region (0.45)
- South America > Colombia > Casanare Department > Llanos Basin > Cusiana Field > Mirador Formation (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- North America > United States > Texas > East Texas Salt Basin > East Texas Field > Woodbine Formation (0.98)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
An Integrated Modeling Framework for Simulating Complex Transient Flow in Fractured Reservoirs with 3D High-Quality Grids
Liu, Hui (China University of Petroleum Beijing) | Liao, Xinwei (China University of Petroleum Beijing) | Lie, Knut-Andreas (SINTEF Digital) | Klemetsdal, รธystein (SINTEF Digital) | Bao, Kai (SINTEF Digital) | Zhao, Xiaoliang (China University of Petroleum Beijing) | Johansson, August (SINTEF Digital) | Raynaud, Xavier (SINTEF Digital)
Abstract Modeling near-well transient flow with complex 3D fracture networks poses several challenges: the multiscale nature (millimeters to kilometers), long and deviating well trajectories, intricate fracture networks with fracture-fracture and fracture-well intersections, and high level of reservoir heterogeneities. We address these difficulties by proposing a comprehensive methodology for meshing, discretizing, and simulating transient flow in complex 3D fracture networks based on discrete fracture-matrix models. Our framework consists of three parts: (i) Given deviating wells and planar or nonplanar fractures and faults, we construct highquality 3D grids conforming to wells, hydraulic fractures, faults, and dominating natural fractures. We ensure sufficient mesh quality near important features using transfinite interpolation near wells and hydraulic fractures, combined with adaptive refinement in regions of interest. (ii) With the generated grid, we discretize the governing equations with a fully implicit finite- volume formulation with an inner-boundary well model and discrete fracture model. (iii) Finally, we analyze the results using suitable visualization tools, both for pressure-transient curves and 3D matrix/fracture data. The framework enables high-resolution numerical modeling of transient flow with complex fracture networks in 3D. We demonstrate the capacities through simple validation cases with comparisons against an industry-standard commercial well-testing software but also present highly complex cases with long and deviating well trajectories and highly detailed fracture networks. We present and analyze flow-transient behavior coupling the wellbore, the fracture network, and the matrix. We also present an approach to reliably diagnose complex multiple flow regimes on the pressure-transient curves combined with different-scale spatial pressure distribution. Comparison against the commercial software indicates that our framework does not introduce adverse grid-orientation effects for non-K-orthogonal grids which is able to robustly handle the details for fracture-network heterogeneities in 3D reservoirs. Overall, our framework is robust for simulating and analyzing realistic second-level transient effects and short-term well performance with complex fracture networks and heterogeneities. Detailed description of the 3D fracture networks, and accurate simulation of the near-well transient flow behavior can be achieved, which provides confidence to interpret the dynamic flow data at different scales and observe transport mechanisms in unconventional fractured reservoirs with multiple levels of heterogeneity.
- North America > United States > Texas (0.68)
- South America (0.68)
A Unified Thermal-Reactive Compositional Simulation Framework for Modeling CO2 Sequestration at Various Scales
Wapperom, M. (TU Delft) | Lyu, X. (China University of Petroleum Beijing) | Nichita, D. V. (University of Pau) | Voskov, D. (TU Delft, Stanford)
Abstract In this work, we present a unified framework for the simulation of CO2 sequestration problems at various time and space scales. The parametrization technique utilizes thermodynamic state-dependent operators expressing the governing equations for the thermal-compositional-reactive system to solve the nonlinear problem. This approach provides flexibility in the assembly of the Jacobian, which allows straightforward implementation of advanced thermodynamics. We validate our simulation framework through several simulation studies including complex physical phenomena relevant to CCUS. The proposed simulation framework is validated against a set of numerical and experimental benchmark tests, demonstrating the efficiency and accuracy of the modeling framework for CCUS-related subsurface applications. Important physical phenomena resulting from the complex thermodynamic interactions of CO2 and impurities with reservoir fluids can be accurately captured now in detailed dynamic simulation. The investigated simulation scenarios include a reproduction of lab experiments at the core scale, investigation of macro-scale analog model and simulation of large-scale industrial application. The simulation time can also span from hours to years among various applications. Complex thermal-compositional-reactive phenomena can be addressed at each of these space and time scales. The unified thermodynamic description allows us to perform all these simulations for a reasonable CPU time due to advanced parametrization techniques and efficient GPU capabilities in our in-house reservoir simulator DARTS.
- North America > United States (0.46)
- Asia (0.28)
- Europe > Netherlands > Rijswijk License > Pernis Field > Holland Greensand Formation (0.99)
- Europe > Netherlands > Rijswijk License > Pernis Field > De Lier Formation (0.99)
Maximizing Recovery and Reducing Well Cost Using Herringbone Multilateral Horizontal Well Drilling and Completion Technology
Zhang, Xiaocheng (CNOOC China Limited, TianJin Branch) | Xie, Tao (State Key Laboratory Offshore Oil Exploitation CNOOC China Limited) | Huo, Hongbo (CNOOC China Limited, TianJin Branch) | He, Ruibing (State Key Laboratory Offshore Oil Exploitation CNOOC China Limited) | Lin, Hai (CNOOC China Limited, TianJin Branch) | Hou, Xinxin (State Key Laboratory Offshore Oil Exploitation CNOOC China Limited) | Xu, Dongsheng (CNOOC China Limited, TianJin Branch)
Abstract With the in-depth development of Bohai Oilfield, China National Offshore Oil Corporation (CNOOC), the water cut of some old wells become too high to produce while nearby remaining recoverable reserves are still considerable. In order to maximize recovery and reduce well construction cost, herringbone multilateral horizontal well drilling and completion technology is employed to increase drainage area of single well and make full use of well slot and old wellbore. Considering the current development of oilfield and the geological characteristics of reservoir, the technical difficulties of herringbone multilateral horizontal well drilling and completion technology including high build-up rate, easy blockage of drilling tools in the sidetracking in open hole, easy collapse and instability of sandwich wall and high requirements for drilling fluid performance are analyzed and solved. This technology has been successfully applied in three wells with total 6 branches and the production of three wells is twice higher than that of conventional horizontal wells with no water cut, which fully verified the reliability of the branch well tools and the feasibility of the technology. Herringbone multilateral horizontal well drilling and completion technology provides a new idea for the treatment of low production and low efficiency wells in a sustainable way and will be widely promoted and applied in Bohai oilfield, which can also provide reference for other high water cut oilfields.
- Asia > China (1.00)
- Asia > Russia > Ural Federal District > Yamalo-Nenets Autonomous Okrug > Tazovksy District (0.28)
- Asia > Russia > Siberian Federal District > Krasnoyarsk Krai (0.28)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > Asia Government > China Government (0.55)
- Asia > Russia > Siberian Federal District > Krasnoyarsk Krai > Vankorskaya Area > Vankorskoye Field (0.99)
- Asia > Russia > Siberian Federal District > Irkutsk Oblast > Kataganskiy District > East Siberian Basin > Nepa-Botuoba Basin > Verhnechonskoye Field (0.99)
- Asia > Russia > Ural Federal District > Yamalo-Nenets Autonomous Okrug > Tazovksy District > West Siberian Basin > South Kara/Yamal Basin > Messoyakhskoye Field (0.97)
- (2 more...)
The Development and Field Applications of Ultra-Short Radial Radius Drilling Technology in Low Permeable Reservoir of Western South China Sea
Guan, Shen (China University of Petroleum Beijing) | Liu, Shujie (CNOOC China Limited-Hainan) | Yang, Jin (China University of Petroleum Beijing) | Liu, Zhiqin (CNOOC China Limited-Zhanjiang) | Xu, Dongsheng (China University of Petroleum Beijing) | Zhao, Yuhang (China University of Petroleum Beijing) | Ma, Kuo (China University of Petroleum Beijing) | Zhang, Xun (China University of Petroleum Beijing) | Ling, Tong (China University of Petroleum Beijing)
Abstract Weizhou Oilfield, located in Beibu Gulf Basin, is a complex fault-block structure oilfield formed at the late periods of the Eocene epoch. The reservoir is in the second member of Liushagang formation, of which lithology is mainly argillaceous siltstone, with high shale content, and is characterized by strong heterogeneity with rapid transition of horizontal pay zone, low porosity and permeability, poor oil recovery due to early-stage extraction through conventional well completion and perforation. In order to expand the drainage area of reservoir and improve the connectivity of the reservoir for improvement of control reserves and enhance oil recovery, the research of "Ultra-short Radius Well Drilling Technology was carried out. The Multi-lateral Ultra-short Radius Well Drilling Technology refers to a novel multi-lateral horizontal well with a radius of curvature of 1~3m or even less, which is completed by special flexible drill pipe composed of mechanical flexible units. Ultra-short Radial Radius Drilling Technology is used in land oilfields in the early stage, which is expected to not only improve recovery and production, but also reduce drilling operation cost, so it is considered as an important measure for enhance oil recovery (EOR), further exploration of residual oil, and stable production in oilfields, and can be suitable for the development of low permeable reservoirs, thin pay zone, and other reservoirs. However, the key challenges include: 1) build-up with dogleg severity of greater than 10ยฐ/m; 2) conventional drill pipes cannot meet the demand of high dogleg severity and horizontal drilling. Since there is no case available for reference in the early stage of applying "Ultra-short Radial Radius Drilling Technology" in offshore oilfields, besides the aforementioned challenges are for onshore oilfields, other challenges for application of this technology offshore include: (1) Staggering high offshore operation cost, and strict requirement for work schedule. During offshore drilling operation, the footage cost is USD $1850/m, the novel technology is required to be used economically; (2) as for offshore operation, most development wells are deviated, and the trajectory is complex. Since offshore oilfields are mostly developed by cluster wells, and the sidetrack process is subject to well trajectory and dogleg severity. In light of build-up with dogleg severity of greater than 10ยฐ/m, conventional drillpipes cannot go through the sidetracking point with dogleg greater than 10ยฐ/m. As a result, novel "Ultra-short Radial Radius Drilling Technology" was introduced by developing a series of novel downhole tools, including highly deviated (23ยฐ) ร209mm whipstock, ร127mm flexible build-up drillpipe, and ร144mm build-up bit, combined with selection of sidetracking point, well trajectory design optimizing, and solving difficulties related to operation. Field application results showed that the "Ultra-short Radial radius Drilling Technology" can lead to enhance oil recovery, and high efficient development of oilfields.
- Asia > China > South China Sea > Beibu Gulf Basin > Jiaowei Formation (0.99)
- Asia > China > South China Sea > Beibu Gulf Basin > Beibu Gulf > Weizhou Field (0.99)
- Asia > China > South China Sea > Beibu Gulf Basin > Beibu Gulf > Block 22/12 > Weizou Formation (0.98)
- Well Drilling > Well Planning > Trajectory design (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- Well Drilling > Drilling Equipment (1.00)
- (3 more...)
CCUS Numerical Simulation Technology and its Application in a Carbonate Reservoir of the Middle East
Li, Qiaoyun (China University of Petroleum Beijing) | Wu, Shuhong (RIPED, PetroChina) | Jia, Han (RIPED, PetroChina) | Wang, Baohua (RIPED, PetroChina) | Deng, Xili (RIPED, PetroChina) | Li, Hua (RIPED, PetroChina) | Fan, Tianyi (RIPED, PetroChina) | Xu, Mingyuan (RIPED, PetroChina)
Abstract Carbon dioxide Utilization and storage technology (CCUS) plays an important role for oil and gas field to further improve oil and gas recovery and achieve the goal of "double carbon" in recent years. Numerical simulation is an essential means for reservoir engineers to study the flow mechanism of CO2 flooding and storage, screen the CCUS technical indicators, predict the enhanced oil recovery and evaluate storage potential. This paper discusses the multiphase and multicomponent mathematical model based on the seepage theory of carbon dioxide flooding and storage, the calculation method of gas-liquid equilibrium based on EOS equation, the miscibility determination technique and two phase P-T flash calculation method. Meanwhile the CCUS numerical simulator developed based on above theoretical model and calculation method. Applying the simulator to CO2 miscible flooding in a carbonate reservoir of the Middle East, the results show that the model and software accurately describes the CO2-EOR seepage mechanism and CO2 miscible displacement process. It effectively predicts the effect of CO2 injection on EOR and the storage potential after CO2 flooding. It can provide feasible technical guidance for the optimization of CO2 utilization and storage programs.
- Asia > Middle East (0.85)
- Europe > Middle East (0.61)
- Africa > Middle East (0.61)
- Research Report > New Finding (0.34)
- Research Report > Experimental Study (0.34)
A New-Type Eccentric Christmas Tree for Hollow Rod Electric Heating in Offshore ESP Wells
Fang, Tao (CNOOC Ltd) | Shang, Baobing (CNOOC Ltd) | Han, Xiaodong (CNOOC Ltd) | Zhao, Shunchao (CNOOC Ltd) | Zhou, Yugang (CNOOC Ltd) | Qi, Yadong (CNOOC Ltd) | Hao, Tongchun (China University of Petroleum Beijing)
Abstract The hollow rod electric heating (HREH) technology can greatly increase the temperature of the fluid in wellbore and improve its fluidity, which is widely used in rod pump wells. Bohai offshore oilfields also have urgent application requirements for HREH technology due to the wide distribution of heavy oil and high waxy crude oil. However, more than 90% of the oil wells there are produced by electric submersible pumps (ESPs). None of these christmas trees in use are suitable for ESP wells using HREH technology. Based on the conventional christmas tree with only one main channel, a new type of eccentric christmas tree, with separated main channel and cable channel, is designed. As with the conventional ones, the main channel works as the flow passage of wellbore fluids. And the cable channel is used to run and pull out the heating cable. The eccentric design of the main channel provides the space for the cable channel. The separate cable channel avoids the cable crossing the main channel, so that the master valve of the christmas tree can be opened and closed normally, which contributes to ensuring safe production. In the meanwhile, the christmas tree can also seal the heating cable owing to some special design. This new device has been successfully tested on 6 ESP wells in Bohai Bay. After the installation of the christmas tree, the cable was smoothly run down to the predetermined depth. The construction operation was simple and convenient. There was no oil or gas leakage at wellhead after it was put into use. The wellhead temperature of all these wells reached above 50ยฐC and no wax deposited in tubing any more, verifying its safety and reliability. This new type of safe and reliable christmas tree lays a solid foundation for the popularization and application of HREH technology, especially in those waxy oil wells and heavy oil wells with ESPs.
- Asia > China (0.48)
- North America > Canada > Alberta (0.30)
- Asia > Middle East (0.29)
- North America > United States > Texas (0.28)
A Semi-Analytical Model for Water Injection Wells in Tight Reservoir Considering the Multi-Dynamic Closure Phenomenon- Case Studies in X Oilfield, China
Wang, Zhipeng (China University of Petroleum Beijing) | Ning, Zhengfu (China University of Petroleum Beijing) | Guo, Wenting (China University of Petroleum Beijing) | Cheng, Qidi (Xinjiang Oil Field Company) | Wang, Wuchao (China University of Petroleum Beijing) | Li, Gexuan (China University of Petroleum Beijing) | Wang, Yang (China University of Petroleum Beijing)
Abstract It is well known that waterflooding will induce fractures. The extensive direction, length, and conductivity of the induced fractures will largely determine the performance of producing wells. The quantitative characterization of the fractures can help prevent water breakthrough in time. This paper proposes the waterflooding-induced dynamic fracture model (WIDF) to monitor the fracture half-length at any time and extend the stable production period. The rock mechanics principles are applied to characterize the dynamic extension and closure of fractures during water injection and build-up periods. The model was solved using the point source function approach. The phenomenon of multi-dynamic closure causes the fluid to be squeezed several times, creating a storage effect and a non-constant conductivity within the fracture. Experimental results show that the conductivity of water injection-induced fracture follows an exponential function. Finally, Duhamel's principle was used to couple the pressure response of the wellbore and the fracture. The field case is shown in the paper to verify the accuracy and practicality of the WIDF model. Multi-peak appears in the pressure derivative curves. The actual data match well, and the parameter values obtained are close to the actual values. However, the conventional finite-conductivity model treats pressure response data with multiple peaks as incorrect values. This behavior will result in the length of dynamic closed fracture being ignored and the interpreted fracture half-length being smaller than the actual value. Misidentification of fracture lengths will affect the determination of reasonable injection volumes and even cause producing water early, which can severely impact the performance of production wells. The storage effect caused by multiple dynamic fracture closures reasonably explains the significant storage effect obtained by the conventional model. The WIDF model enables researchers can monitor induced fracture half-length at any time, allowing them to take measures in time. The model has been successfully applied to the X oilfield in China and has significantly improved the performance of injection wells and increased the stable production period of production wells. The fluid compressed by dynamic fractures reasonably explains the significant storage effect in injection wells. The identification and interpretation of multiple dynamic fracture closure phenomenon make us obtain more accurate fracture half-length parameters, which monitors and suppresses the occurrence of water breakthrough effectively and help researchers take measures to increase the stable production period of production wells.
- Asia > China (1.00)
- North America > United States > Texas (0.28)
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Lifecycle > Disposal/Injection (0.81)
- Asia > China > Shanxi > Ordos Basin > Changqing Field (0.99)
- Asia > China > Shaanxi > Ordos Basin > Changqing Field (0.99)
- Asia > China > Ningxia > Ordos Basin > Changqing Field (0.99)
- (3 more...)