联合船测海深、重力异常和垂直重力梯度异常数据,构建了中国海及周边地区1′×1′海底地形模型。船测海深数据主要用于构建波长大于200km波段的海底地形,垂直重力梯度异常数据用于反演100-200km波段内的海底地形,而重力异常数据用...联合船测海深、重力异常和垂直重力梯度异常数据,构建了中国海及周边地区1′×1′海底地形模型。船测海深数据主要用于构建波长大于200km波段的海底地形,垂直重力梯度异常数据用于反演100-200km波段内的海底地形,而重力异常数据用于反演波长小于100km波段的海底地形。以船测海深为检核参考,考察了本文模型在南中国海和菲律宾海地区的精度。结果表明,本文模型精度优于ETOPO1、GEBCO和DTU10模型,在南中国海地区与斯克里普斯海洋研究所（Scripps Institute of Oceanography,SIO）的海底地形模型V15.1精度一致,在菲律宾海地区较V15.1模型精度提高了约8.2%。展开更多
The Bamiléké Plateau represents a key domain in the understanding of the geodynamics associated with the central Cameroon shear. The study aimed to highlight the subsurface architecture of the plateaus basem...The Bamiléké Plateau represents a key domain in the understanding of the geodynamics associated with the central Cameroon shear. The study aimed to highlight the subsurface architecture of the plateaus basement setting with focus on high potential areas for hydrogeological and mining development projects. To this end, geological field observations were carried out. Since the structures sought were near-surface, a separation approach based on the upward continuation method was applied to the Bouguer anomaly grid. A set of processing techniques, including vertical derivative or DZ, analytical signal or SA and categorization of gravity signatures, was applied to generate the residual map. The synthesis geological model, obtained from analysis and interpretation of the various transformed maps and 2.5D modeling of two gravity profiles P1 and P2 highlights the following features: 1) intrusions of steep-sided granitic batholiths from Dschang to Bandjoun (profile P1), increasing in width from NW (Dschang) to SE (Bandjoun);2) larger volume batholiths with moderate sides located at Bafang and Bangangté (profile P1). These plutonic massifs were weakened by brittle deformation, which favored the emplacement of phonolite or anorthosite dykes within them. The emplacement of these dykes was accompanied by compressional faults with high dip between Dschang and Bandjoun and extensional faults with medium dip between Bafang and Bangangté. These fault zones (trending N85E to N95E) are ideal for hydrogeological investigations in a basement setting, as well as a series of dyke networks that could potentially be preferred zones for the circulation and accumulation of useful substances. The resulting geological sections P1 and P2 highlight the influence of granitic intrusions in the geological system of the study area, as well as the structural control associated with the various dyke intrusions. All the models obtained can serve as fundamental references for hydrogeological and mining exploration project on the Bamiléké Plateau展开更多
In this work, gravity anomalies from the XGM2016 global gravity model are used to study the basement of the Yaounde, Yoko area. The aim is to locate the characteristic tectonic faults and to characterize the geometry ...In this work, gravity anomalies from the XGM2016 global gravity model are used to study the basement of the Yaounde, Yoko area. The aim is to locate the characteristic tectonic faults and to characterize the geometry of the basement of these localities in order to improve the knowledge of the structural and tectonic basement of the study area. Numerical filters (vertical gradient, horizontal gradient, upward continuation) and Euler deconvolution were applied to the gravity anomalies respectively for qualitative and quantitative analysis. The results of the qualitative analysis allowed us to establish the lineament map of the study area;ranging from 0 to 35 km depth. For the quantitative analysis, the work is done in two parts: 1) highlighting the distribution of depths of geological structures in the basement of the study area;2) 2D1/2 modeling of geological structures to highlight the geometry of the basement of Yaounde, Yoko area. Thus, from five suitably selected profiles, the established models reveal the presence of eight blocks of geological structures of different densities and analyze their implications on the Sanaga Fault. Moreover, the models show that the positive anomalies characteristics for the Sanaga Fault reflect the anomalous character due to the strong dominance of the shale intrusion in the basement.展开更多
文摘联合船测海深、重力异常和垂直重力梯度异常数据,构建了中国海及周边地区1′×1′海底地形模型。船测海深数据主要用于构建波长大于200km波段的海底地形,垂直重力梯度异常数据用于反演100-200km波段内的海底地形,而重力异常数据用于反演波长小于100km波段的海底地形。以船测海深为检核参考,考察了本文模型在南中国海和菲律宾海地区的精度。结果表明,本文模型精度优于ETOPO1、GEBCO和DTU10模型,在南中国海地区与斯克里普斯海洋研究所（Scripps Institute of Oceanography,SIO）的海底地形模型V15.1精度一致,在菲律宾海地区较V15.1模型精度提高了约8.2%。
文摘The Bamiléké Plateau represents a key domain in the understanding of the geodynamics associated with the central Cameroon shear. The study aimed to highlight the subsurface architecture of the plateaus basement setting with focus on high potential areas for hydrogeological and mining development projects. To this end, geological field observations were carried out. Since the structures sought were near-surface, a separation approach based on the upward continuation method was applied to the Bouguer anomaly grid. A set of processing techniques, including vertical derivative or DZ, analytical signal or SA and categorization of gravity signatures, was applied to generate the residual map. The synthesis geological model, obtained from analysis and interpretation of the various transformed maps and 2.5D modeling of two gravity profiles P1 and P2 highlights the following features: 1) intrusions of steep-sided granitic batholiths from Dschang to Bandjoun (profile P1), increasing in width from NW (Dschang) to SE (Bandjoun);2) larger volume batholiths with moderate sides located at Bafang and Bangangté (profile P1). These plutonic massifs were weakened by brittle deformation, which favored the emplacement of phonolite or anorthosite dykes within them. The emplacement of these dykes was accompanied by compressional faults with high dip between Dschang and Bandjoun and extensional faults with medium dip between Bafang and Bangangté. These fault zones (trending N85E to N95E) are ideal for hydrogeological investigations in a basement setting, as well as a series of dyke networks that could potentially be preferred zones for the circulation and accumulation of useful substances. The resulting geological sections P1 and P2 highlight the influence of granitic intrusions in the geological system of the study area, as well as the structural control associated with the various dyke intrusions. All the models obtained can serve as fundamental references for hydrogeological and mining exploration project on the Bamiléké Plateau
文摘In this work, gravity anomalies from the XGM2016 global gravity model are used to study the basement of the Yaounde, Yoko area. The aim is to locate the characteristic tectonic faults and to characterize the geometry of the basement of these localities in order to improve the knowledge of the structural and tectonic basement of the study area. Numerical filters (vertical gradient, horizontal gradient, upward continuation) and Euler deconvolution were applied to the gravity anomalies respectively for qualitative and quantitative analysis. The results of the qualitative analysis allowed us to establish the lineament map of the study area;ranging from 0 to 35 km depth. For the quantitative analysis, the work is done in two parts: 1) highlighting the distribution of depths of geological structures in the basement of the study area;2) 2D1/2 modeling of geological structures to highlight the geometry of the basement of Yaounde, Yoko area. Thus, from five suitably selected profiles, the established models reveal the presence of eight blocks of geological structures of different densities and analyze their implications on the Sanaga Fault. Moreover, the models show that the positive anomalies characteristics for the Sanaga Fault reflect the anomalous character due to the strong dominance of the shale intrusion in the basement.
