High-resolution exploration for lithologic targets confronted with difficulties due to the original brought out from geophysical and geologic characteristics of the loess hills and the very thick deserts in Ordos. Sci...High-resolution exploration for lithologic targets confronted with difficulties due to the original brought out from geophysical and geologic characteristics of the loess hills and the very thick deserts in Ordos. Scientific research since mid 1990s has conducted three acquisition techniques including the high-resolution crooked line survey in valleys, high-resolution multiple straight line survey and 3D survey, under different surface conditions and for different geological targets.展开更多
There are many thrust-related structures occurring in the Paleozoic strata of the Niushou Mountain in the central part of Ningxia Hui Autonomous Region. The fault-related folds are the typical structures in this area....There are many thrust-related structures occurring in the Paleozoic strata of the Niushou Mountain in the central part of Ningxia Hui Autonomous Region. The fault-related folds are the typical structures in this area. Based on the analysis about these structures and their relationships, the processes by which these structures of the Miboshan Formation were formed are reconstructed, and the strata underwent about three stages of deformation: (1) horizontal shortening, (2) folding, and (3) thrusting. And the fact that the Niushou Mountain is the leading edge of an old thrust sheet was proved, the Niushou Mountain,the Daluo Mountain and the Xiaoluo Mountain together constitute the front part of this old thrust zone,so the Niushou Mountain and the Ordovician strata in the central and southern parts of Ningxia now are likely allochthons. In the period from middle Ordovician to Devonian, the areas of the central and southern Ningxia belonged to the back-arc foreland basin of North Qilianshan orogen, which was adjacent to the continent in the north. In the later part of the early Paleozoic period, the Niushou Mountain was formed after the closure of the back-arc foreland basin.展开更多
文摘High-resolution exploration for lithologic targets confronted with difficulties due to the original brought out from geophysical and geologic characteristics of the loess hills and the very thick deserts in Ordos. Scientific research since mid 1990s has conducted three acquisition techniques including the high-resolution crooked line survey in valleys, high-resolution multiple straight line survey and 3D survey, under different surface conditions and for different geological targets.
基金supported by National Science Foundation(Grant No.4983402).
文摘There are many thrust-related structures occurring in the Paleozoic strata of the Niushou Mountain in the central part of Ningxia Hui Autonomous Region. The fault-related folds are the typical structures in this area. Based on the analysis about these structures and their relationships, the processes by which these structures of the Miboshan Formation were formed are reconstructed, and the strata underwent about three stages of deformation: (1) horizontal shortening, (2) folding, and (3) thrusting. And the fact that the Niushou Mountain is the leading edge of an old thrust sheet was proved, the Niushou Mountain,the Daluo Mountain and the Xiaoluo Mountain together constitute the front part of this old thrust zone,so the Niushou Mountain and the Ordovician strata in the central and southern parts of Ningxia now are likely allochthons. In the period from middle Ordovician to Devonian, the areas of the central and southern Ningxia belonged to the back-arc foreland basin of North Qilianshan orogen, which was adjacent to the continent in the north. In the later part of the early Paleozoic period, the Niushou Mountain was formed after the closure of the back-arc foreland basin.
