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Xinjiang Uyghur Autonomous Region
In recent years, with continuous improvements in ultra-deep oil and gas exploration theory and technology, domestic onshore ultra-deep oil and gas exploration has continued to make breakthroughs, providing an important replacement field for CNPC's upstream business development and large-scale increase of reserves and production. The proven oil and gas reserves in ultra-deep reservoirs in Tarim Basin account for more than 50% of the proven oil and gas in ultra-deep reservoirs in China, and Tarim has become the main field for onshore ultra-deep exploration in China. This is not only due to the innovation of ultra-deep oil and gas geological theory, but also due to the breakthrough of ultra-deep geophysical technology. Tarim ultra deep oil and gas exploration faces many challenges: accurate imaging of steeply ultra-deep structures in complex mountains; better recovery of weak signals; enhanced imaging resolution in the ultra-deep subsalt of large desert areas; ultra-deep imaging in thick loess covered areas and other problems restricts the process and economic development of ultra-deep oil and gas exploration in basin. Therefore, there is an urgent need to study theoretical technologies suitable for ultra-deep geophysical acquisition, weak signal processing and imaging, as well as ultra-deep reservoir prediction and fluid identification under different geological conditions.
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > Asia Government > China Government (0.40)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- North America > United States > Louisiana > China Field (0.95)
Using seismic petrophysical modeling and prestack simultaneous inversion to provide insights into the physical properties of uranium-bearing reservoirs: Implications for favorable sites of sandstone-hosted uranium deposits
Wu, Qubo (China University of Geosciences (Beijing), Beijing Research Institute of Uranium Geology) | Wang, Yanchun (China University of Geosciences (Beijing)) | Huang, Yucheng (Beijing Research Institute of Uranium Geology) | Qiao, Baoping (Beijing Research Institute of Uranium Geology) | Cao, Chengyin (Beijing Research Institute of Uranium Geology) | Li, Ziwei (Beijing Research Institute of Uranium Geology) | Yu, Xiang (China National Uranium Corporation)
ABSTRACT Seismic prospecting has been accepted as one of the most widely available methods for exploring sandstone-hosted uranium deposits (SUDs). However, conventional seismic interpretation faces a challenge in the identification and characterization of a uranium reservoir’s complexity. How to characterize in detail a uranium reservoir’s physical complexity and effectively improve uranium reservoir prediction accuracy remain unresolved problems. To address this, we develop a novel combination of petrophysical modeling and prestack simultaneous inversion to understand in detail the physical properties of uranium-bearing reservoirs and efficiently predict favorable SUD sites. First, we develop a workflow of rock-physics modeling for SUD logs using the Xu-White method to calculate the modulus of elasticity of the grain matrix; subsequently, we extend the Walton model for the modulus prediction of the dry rocks and the Gassmann equation for one of the saturated rocks after a massive calculation test; and then, we predict the S-wave data used for the following inversion. Second, we execute a prestack simultaneous inversion to obtain the petrophysical parameters (e.g., P-impedance, density [], shear modulus [], Lamé coefficient [], and Young’s modulus) that can provide insights into the physical properties of a uranium metallogenic environment. Accordingly, we discover that sites bearing uranium mineralization strongly correspond to areas with low elastic-parameter values (especially and ), whereas nonuranium anomalies occur in high-value sites. This indicates that weakened elastic characteristics are caused by the enhancement of the total organic content and total clay mineral volumes of the uranium-bearing layers. In summary, the developed combination approach can yield an effective and accurate characterization of the geologic properties of uranium-bearing formations, and it can provide prediction factors (e.g., parameters related to the shear modulus) for uranium mineralization.
- Asia > China (1.00)
- North America > Canada (0.68)
- Geology > Mineral > Silicate (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock (0.47)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Sandstone (0.37)
- Geophysics > Seismic Surveying > Seismic Processing (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling > Seismic Inversion (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (1.00)
- Asia > Pakistan > Upper Indus Basin > Potwar Basin (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Junggar Basin (0.99)
- Asia > China > South China Sea > Zhujiangkou Basin (0.99)
- (7 more...)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic modeling (1.00)
- Health, Safety, Environment & Sustainability > Environment > Naturally occurring radioactive materials (1.00)
Quantitative prediction of the fracture scale based on frequency-dependent S-wave splitting
Yu, Peilin (Chengdu University of Technology) | Yang, Yuyong (Chengdu University of Technology, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation) | Qi, Qiaomu (Chengdu University of Technology, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation) | Zhou, Huailai (Chengdu University of Technology, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation) | Wang, Yuanjun (Chengdu University of Technology, China West Normal University)
ABSTRACT The development of natural fractures has a significant impact on underground reservoirs and leads to seismic anisotropy. Furthermore, the scale of natural fractures directly affects oil and gas preservation, hydraulic fracture construction, and the production development of shale reservoirs. The S-wave anisotropy is a frequency-dependent parameter and the change in S-wave anisotropy with frequency is a function of the fracture scale. We develop an innovative method for predicting the fracture scale quantitatively using frequency-dependent S-wave anisotropy. The quantitative relationship between different fracture scales and the frequency-dependent response of the S-wave splitting (SWS) anisotropy can be obtained using a dynamic rock-physics model. The frequency-dependent S-wave anisotropy is calculated via SWS analysis in the frequency domain, after which this quantitative relationship and the calculated frequency-dependent response are used to establish an objective function for the inversion of the fracture scale at different depths using the least-squares algorithm. We synthesize data under ideal conditions, test our method, apply our method to field data, and find that the quantitative prediction method of the fracture scale yielded reasonable prediction results. The S-wave anisotropy is calculated based on the SWS analysis from the horizontal components of the upgoing wavefields of the field vertical seismic profile. We compare the fracture scale calculated from logging data using our method, and the results obtained indicate that this method can successfully predict the fracture scale quantitatively.
- Geology > Geological Subdiscipline > Geomechanics (0.88)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.34)
- North America > United States > California > San Joaquin Basin > Lost Hills Field (0.99)
- Asia > Middle East > Oman > Ad Dhahirah Governorate > Fahud Salt Basin > Natih Field (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- (2 more...)
Using seismic petrophysical modeling and prestack simultaneous inversion to provide insights into the physical properties of uranium-bearing reservoirs: Implications for favorable sites of sandstone-hosted uranium deposits
Wu, Qubo (China University of Geosciences (Beijing), Beijing Research Institute of Uranium Geology) | Wang, Yanchun (China University of Geosciences (Beijing)) | Huang, Yucheng (Beijing Research Institute of Uranium Geology) | Qiao, Baoping (Beijing Research Institute of Uranium Geology) | Cao, Chengyin (Beijing Research Institute of Uranium Geology) | Li, Ziwei (Beijing Research Institute of Uranium Geology) | Yu, Xiang (China National Uranium Corporation)
ABSTRACT Seismic prospecting has been accepted as one of the most widely available methods for exploring sandstone-hosted uranium deposits (SUDs). However, conventional seismic interpretation faces a challenge in the identification and characterization of a uranium reservoir’s complexity. How to characterize in detail a uranium reservoir’s physical complexity and effectively improve uranium reservoir prediction accuracy remain unresolved problems. To address this, we develop a novel combination of petrophysical modeling and prestack simultaneous inversion to understand in detail the physical properties of uranium-bearing reservoirs and efficiently predict favorable SUD sites. First, we develop a workflow of rock-physics modeling for SUD logs using the Xu-White method to calculate the modulus of elasticity of the grain matrix; subsequently, we extend the Walton model for the modulus prediction of the dry rocks and the Gassmann equation for one of the saturated rocks after a massive calculation test; and then, we predict the S-wave data used for the following inversion. Second, we execute a prestack simultaneous inversion to obtain the petrophysical parameters (e.g., P-impedance, density [], shear modulus [], Lamé coefficient [], and Young’s modulus) that can provide insights into the physical properties of a uranium metallogenic environment. Accordingly, we discover that sites bearing uranium mineralization strongly correspond to areas with low elastic-parameter values (especially and ), whereas nonuranium anomalies occur in high-value sites. This indicates that weakened elastic characteristics are caused by the enhancement of the total organic content and total clay mineral volumes of the uranium-bearing layers. In summary, the developed combination approach can yield an effective and accurate characterization of the geologic properties of uranium-bearing formations, and it can provide prediction factors (e.g., parameters related to the shear modulus) for uranium mineralization.
- Asia > China (1.00)
- North America > Canada (0.68)
- Geology > Mineral > Silicate (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock (0.47)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Sandstone (0.37)
- Geophysics > Seismic Surveying > Seismic Processing (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling > Seismic Inversion (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (1.00)
- Asia > Pakistan > Upper Indus Basin > Potwar Basin (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Junggar Basin (0.99)
- Asia > China > South China Sea > Zhujiangkou Basin (0.99)
- (7 more...)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic modeling (1.00)
- Health, Safety, Environment & Sustainability > Environment > Naturally occurring radioactive materials (1.00)
Abstract The Central Sumatra Basin is a vast sedimentary basin that has been proven to produce hydrocarbon. The basin comprises several subbasins that are not sufficiently imaged by conventional seismic reflection profiles and limited well-log data, particularly in the nearshore area to the east. This research aims to delineate sedimentary subbasins, interpret the subsurface geologic model, and identify geologic structures beneath the eastern part of the Central Sumatra Basin using integrated geophysical gravity, seismic profiles, and well-log data. Three-dimensional gravity inversion modeling results indicate that the pre-Tertiary granitic basement is a continental crust with a mass density value of 2.67 gr/cc. The modeling results indicate that the sedimentary rock is composed of Early Oligocene–Middle Miocene sedimentary rock, with a mass density of 2.35 gr/cc, arranged from bottom to top. The residual gravity anomaly model identifies 13 sedimentary subbasins with structural features such as basement height, graben, and fault mapped in a relatively northwest–southeast direction. Moreover, based on the graben pattern and the basement high beneath the eastern Central Sumatra Basin, many structural patterns support the development of petroleum systems similar to that of the western part of the basin, which has already produced hydrocarbon. Our research also revealed the thickness of the Sihapas Formation in the eastern part of the basin, which shows great potential as a hydrocarbon reservoir. The results show that integrated analysis of many geophysical data sets can substantially decrease the uncertainty associated with individual data sets and produce more reliable imaging of subsurface geology.
- Phanerozoic > Cenozoic > Neogene > Miocene (0.69)
- Phanerozoic > Cenozoic > Paleogene > Oligocene (0.54)
- Geology > Structural Geology > Tectonics > Plate Tectonics (1.00)
- Geology > Geological Subdiscipline > Economic Geology > Petroleum Geology (0.68)
- Geology > Structural Geology > Tectonics > Compressional Tectonics (0.68)
- (2 more...)
- Geophysics > Seismic Surveying (1.00)
- Geophysics > Gravity Surveying > Gravity Modeling > Gravity Inversion (1.00)
- Geophysics > Borehole Geophysics (1.00)
- North America > United States > Texas > West Gulf Coast Tertiary Basin > Serbin Field (0.99)
- Asia > Indonesia > Sumatra > South Sumatra > South Sumatra Basin (0.99)
- Asia > Indonesia > Sumatra > Riau > Central Sumatra Basin > Rokan Block > Menggala Formation (0.99)
- (6 more...)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Geologic modeling (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
Xianhuai Zhu has significantly advanced the concepts, developments, and application of solutions to seismic imaging below complex near-surface environments. He previously received the SEG Life Membership (2018) and Reginald Fessenden (2012) awards. He is awarded the Virgil Kauffman Gold Medal for his pioneering research and applications of joint tomography using both turning-ray and reflections, which provide a viable tool for the industry to construct near -surface velocity models that are essential for accurate onshore depth imaging in complex geologic settings. Zhu founded Forland Geophysical, which has developed and applied a technique for integrated tomography for velocity model building under complex near-surface conditions such as foothills areas and gas-obscured zones. This work has been applied to multiple projects with great success on several continents and in challenging geologic environments, including onshore basins in China, the United States overthrust, the Andes of South America, Southeast Asia, and the Middle East.
- North America (1.00)
- Asia > China (1.00)
- Geophysics > Seismic Surveying > Surface Seismic Acquisition (1.00)
- Geophysics > Seismic Surveying > Seismic Processing (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling (1.00)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- Asia > China > Sichuan > Sichuan Basin (0.99)
- Asia > China > Jiangsu Basin > Jiangsu Field (0.99)
- Information Technology > Knowledge Management (0.76)
- Information Technology > Communications > Collaboration (0.76)
S-WAVE SEISMIC DATA INTERPRETATION FOR GAS RESERVOIR AT SANHU AREA, QAIDAM BASIN, WEST CHINA
Deng, Zhiwen (China National Petroleum Corporation (BGP INC)) | Zhang, Rui (University of Louisiana at Lafayette) | Wang, Yan (China National Petroleum Corporation (BGP INC)) | Yue, Yuanyuan (China National Petroleum Corporation (BGP INC)) | Xi, Xiaoyu (China National Petroleum Corporation (BGP INC)) | Wang, Xiusong (China National Petroleum Corporation (BGP INC)) | Wang, Jie (China National Petroleum Corporation (BGP INC))
The Qigequan Formation at the Sanhu area of the Qaidam Basin in western China is a significant gas production formation. However, the conventional P-wave seismic survey conducted in this region reveals the presence of extensive gas clouds that strongly attenuate P-waves, resulting in substantial uncertainty regarding the subsurface structure. To address this challenge, we undertook a 3D9C (three-dimensional nine-component) seismic survey, producing direct S-wave data unaffected by gas clouds, yielding remarkably clearer subsurface images with a higher level of confidence. The processing of the S-wave data largely utilized conventional P-wave processing techniques, except for shear wave splitting, which produced distinct Fast (S1) and Slow (S2) S-wave datasets. Notably, the S2 data exhibited superior quality compared to the S1 data, enabling us to apply various seismic attributes and inversion techniques to extract geological features. To validate our findings, we cross-referenced the seismic attributes and inversion results with well-log and production data, revealing a pronounced spatial correlation between the gas reservoir and channel structure. Consequently, we have identified channel structures as the prime targets for potential gas reservoirs.#xD;
- Geology > Structural Geology > Tectonics (1.00)
- Geology > Sedimentary Geology (1.00)
- Geology > Geological Subdiscipline > Stratigraphy (0.93)
- (2 more...)
- Geophysics > Seismic Surveying > Seismic Processing > Seismic Migration (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling (0.67)
- North America > United States > Colorado > DJ (Denver-Julesburg) Basin > Wattenberg Field > Niobrara Formation (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- Asia > China > Qinghai > Qaidam Basin (0.99)
Inversion of Fracture Weakness Parameters Based on the 3CVSP Data?Part I: HTI Media Composed of A Single Fracture Set in the Isotropic Background Media
Yang, Yuyong (Chengdu University of Technology, Norwegian University of Science and Technology) | Stovas, Alexey (Norwegian University of Science and Technology) | Qi, Qiaomu (Chengdu University of Technology) | Zhou, Huailai (Chengdu University of Technology)
Natural fractures in oil and gas reservoirs are a crucial factor that cannot be ignored, as they significantly influence the reservoir's petrophysical properties and hydrocarbon development. A horizontal transversely isotropic (HTI) medium composed of a single fracture set in an isotropic background is a typical anisotropic medium. Meanwhile, the shear wave splitting (SWS) is a sensitive response of such anisotropic media, resulting in the generation of fast and slow shear waves. The normal and tangential fracture weaknesses are crucial parameters that characterize the anisotropy of fractured media. We proposed an inversion method for fracture weakness based on three-component vertical seismic profiling (3CVSP) data. Firstly, assuming weak anisotropy and an HTI medium containing single fracture set, we derived a first-order linear approximation of the travel times of the converted fast and slow shear waves (PS1- and PS2-waves) with respect to fracture weakness parameters in the phase velocity domain. By solving for the horizontal projection of the slowness vector, approximate equations of the travel times of the PS1- and PS2-waves were converted from phase velocity domain to the group velocity domain. Furthermore, we devised an inversion workflow consisting of three primary steps: 1. pre-processing the VSP data to derive the travel times and azimuth of the HTI medium; 2. constructing a forward model with undetermined fracture weakness parameters; 3. following the establishment of the objective function, conducting the inversion for the fracture weakness parameters. We demonstrated the reliability of the method through numerical examples and synthetic 3CVSP data. The inversion errors are primarily influenced by the azimuth angle, with minimal influence from the receiver depth. Furthermore, a collective set of inverted results derived from all geophones are more stable and accurate than individual geophones. The application to actual 3CVSP data further confirmed the effectiveness of our approach.
- Asia > China (0.46)
- North America > United States (0.28)
- North America > United States > Gulf of Mexico > Central GOM > East Gulf Coast Tertiary Basin > Green Canyon > Block 744 > Atlantis Field (0.99)
- North America > United States > Gulf of Mexico > Central GOM > East Gulf Coast Tertiary Basin > Green Canyon > Block 743 > Atlantis Field (0.99)
- North America > United States > Gulf of Mexico > Central GOM > East Gulf Coast Tertiary Basin > Green Canyon > Block 742 > Atlantis Field (0.99)
- (3 more...)
Frequency-dependent elastic properties of fracture-induced VTI rocks in a fluid-saturated porous and microcracked background
Wang, Wenhao (China University of Petroleum (East China)) | Li, Shengqing (China University of Petroleum (East China), Laoshan National Laboratory) | Guo, Junxin (Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology, Southern University of Science and Technology) | Zhang, Chengsen (PetroChina Tarim Oilfield Company) | Duan, Wenxing (PetroChina Tarim Oilfield Company) | Su, Yuanda (China University of Petroleum (East China), Laoshan National Laboratory) | Tang, Xiao-Ming (China University of Petroleum (East China), Laoshan National Laboratory)
Fractures are widely distributed underground. The stiffness matrix of fractured rocks has been extensively investigated in a fluid-saturated porous background medium. However, the existing stiffness models only incorporated the attenuation mechanism of wave-induced fluid flow (WIFF). For macroscopic fractures, the elastic scattering (ES) of fractures cannot be ignored. To alleviate this issue, a frequency-dependent stiffness matrix model was developed, including the mesoscopic wave-induced fluid flow between fractures and background (FB-WIFF), the microscopic squirt flow, and the macroscopic ES from the fractures. By combining the far-field scattered wavefields of normal incident P and SV waves with the linear slip theory, the dynamic full-stiffness matrices for fracture-induced effective VTI rocks in a fluid-saturated porous and microcracked background were derived. Then, the P, SV, and SH wave velocities and attenuation can be obtained through the Kelvin-Christoffel equation. The results indicate that the FB-WIFF mechanism significantly affects the velocities and attenuation of the P and SV waves, but has nearly no effect on the SH wave, while the squirt flow and ES mechanisms affect the velocities and attenuation of both the P, SV, and SH waves. For validation, the model was compared with existing models and previous experimental ultrasonic data.
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- Asia > China > Sichuan > Sichuan Basin (0.95)
Color origin and its sedimentary and paleoenvironmental significance of the Permian-Triassic strata in the Ordos Basin, China
Tan, Cong (Research Institute of Petroleum Exploration and Development) | Yu, Bingsong (China University of Geosciences) | Liu, Ce (Research Institute of Petroleum Exploration and Development) | Cao, Zhenglin (Research Institute of Petroleum Exploration and Development) | Bi, He (Research Institute of Petroleum Exploration and Development) | Jin, Hui (Research Institute of Petroleum Exploration and Development) | Yang, Rongjun (Research Institute of Petroleum Exploration and Development)
Abstract The Permian-Triassic strata in the Ordos Basin deposit a colorful set of strata. Although there have been many studies on oil and gas resources here, little attention has been paid to the genesis mechanism of its color. To analyze the color origin of the Permian-Triassic claystones and to clarify the dialectical relationship between rock color and sedimentary environment, petrological and geochemical methods such as polarization microscope, scan electron microscope, X-ray diffractometer, and inductively coupled plasma-mass spectrometer are used. The results indicate that the minerals with different colors, composition, and content serve as colorants in sedimentary rocks, with the predominant dyeing component in dark claystones being the organic matter, whereas red beds primarily acquire their color from hematite and other ferric minerals. In addition, different rock colors correspond to distinct chemical composition variations. The black-gray rocks of the Yanchang and Shihezi Formations have high total organic carbon content, Fe/Fe, V/Cr, and low CaO/(MgO × Al2O3) and Sr/Cu, whereas the red-brown rocks of the Liujiagou and Heshanggou Formations exhibit the opposite. Therefore, different colors of the rocks stem from their different mineral and chemical compositions, which in turn influenced by the changes in the paleoclimate, paleoenvironment, and tectonic movements. Comprehensive analysis of color, mineral, and chemical composition reveals the evolution process of paleoclimate and paleoenvironment in the Ordos Basin from the late Permian to Triassic, beginning with a warm humid climate characterized by a weak oxidation environment in the Shihezi and Shiqianfeng Formations, transitioning to a hot arid climate in the Liujiagou and Heshanggou Formations, and returning to a warm humid climate with a weak oxidation environment in the Zhifang and Yanchang Formations. This evolution history aligns with the global tectonic and climate evolution. Overall, systematic analysis of sedimentary rock color can provide an important basis for the study of the paleoclimate and paleoenvironment.
- Asia > China > Shanxi Province (0.83)
- Asia > China > Shaanxi Province (0.83)
- Asia > China > Gansu Province (0.83)
- Phanerozoic > Mesozoic > Triassic (1.00)
- Phanerozoic > Paleozoic > Permian > Lopingian (0.34)
- Geology > Structural Geology > Tectonics (1.00)
- Geology > Sedimentary Geology > Depositional Environment (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock (1.00)
- (2 more...)
- North America > United States > Wyoming > Bighorn Basin (0.99)
- North America > United States > Montana > Bighorn Basin (0.99)
- Europe > Netherlands > German Basin (0.99)
- (33 more...)