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61.
Oceanology - The kinetic energy of six jets of the Antarctic Circumpolar Current (ACC) and of the cyclonic and anticyclonic mesoscale eddies generated by these jets is studied in application to the... 相似文献
62.
Lithology and Mineral Resources - The Haléo-Danielle Plateau bauxite deposit forms the largest part of the 15 km long Minim-Martap Bauxite ore district in the Adamawa Region of Cameroon. The... 相似文献
63.
Mikhalsky E. V. Alexeev N. L. Kamenev I. A. Larionov A. N. Gogolev M. A. Svetov S. A. Kunakkuzin E. L. 《Geotectonics》2020,54(3):285-307
Geotectonics - An assemblage of mafic granulites (schists), plagiogneisses, and metasedimentary rocks, which is referred to as the Filla Series, is exposed in the Rauer Islands (opposite the... 相似文献
64.
Adushkin V. V. Varypaev A. V. Kushnir A. F. Sanina I. A. 《Doklady Earth Sciences》2020,493(1):548-551
Doklady Earth Sciences - The results of recording and determining the locations of seismic events triggered by industrial explosions conducted by OJSC Kombinat KMAruda at the Korobkovskoe iron ore... 相似文献
65.
Astronomy Reports - Astronomical observations indicate a high abundance of methanol molecules in the gas phase of molecular-cloud dense cores, which cannot be explained by gas-phase chemical... 相似文献
66.
Zhang Shuai Xiao Keyan Carranza Emmanuel John M. Yang Fan 《Natural Resources Research》2019,28(3):645-664
Natural Resources Research - This study tested and compared the mineral potential mapping capabilities of the random forest (RF) and maximum entropy (MaxEnt) algorithms using gold deposit... 相似文献
67.
Geomagnetism and Aeronomy - It is possible that the radially independent, spatial-spectral components of the energy and power of the potential part of the main geomagnetic field were determined and... 相似文献
68.
Water Resources - Hydrogen sulfide, like other sulfides, is formed in aquatic environments due to sulphate reduction processes and putrefactive decomposition of organic matter of bottom sediments,... 相似文献
69.
E. A. MacLagan E. L. Walton C. D. K. Herd B. Rivard 《Meteoritics & planetary science》2020,55(7):1564-1580
Hyperspectral imaging can be used to rapidly identify and map the spatial distributions of many minerals. Here, hyperspectral mapping in three wavelength regions (visible and near‐infrared, shortwave infrared, and thermal infrared) was applied to drill cores (ST001, ST002, and ST003) penetrating a continuous sequence of crater‐fill breccias from the Steen River impact structure in Alberta, Canada. The combined data sets reveal distinct mineralogical layering, with breccias derived predominantly from sedimentary rocks overlying those derived from granitic basement. This stratigraphy demonstrates that the breccias were not appreciably disturbed following deposition, which is inconsistent with formation models of similar breccias (suevites) by explosive impact melt–fluid interaction. At Steen River, volatiles from sedimentary target rocks were an inherent part of forming these enigmatic breccias. Approximately three quarters of terrestrial impact structures contain sedimentary target rocks; therefore, the role of volatiles in producing so‐called suevitic breccias may be more widespread than previously realized. The hyperspectral maps, specifically within the SWIR wavelength region, also delineate minerals associated with postimpact hydrothermal activity, including ammoniated clay and feldspar minerals not detectable using traditional techniques. These nitrogen‐bearing minerals may have originated from microbial processes, associated with oil‐ and gas‐producing units in the crater vicinity. Such minerals may have important implications for the production of habitable environments by impact‐induced hydrothermal activity on Earth and Mars. 相似文献
70.
Piret Cécile Dissanayake Nadun Gierke John S. Fornberg Bengt 《Mathematical Geosciences》2020,52(4):477-497
Mathematical Geosciences - A robust, high order modeling approach is introduced, based on the finite difference-based radial basis functions method, for solving the groundwater flow equation in the... 相似文献