Tangi Mahi-par is a fault valley from previews geological period (Pleistocene) where the Kabul basin was a lake and occupied by water, and after the formation of Tangi Mahi-par fault valley, water was drained from thi...Tangi Mahi-par is a fault valley from previews geological period (Pleistocene) where the Kabul basin was a lake and occupied by water, and after the formation of Tangi Mahi-par fault valley, water was drained from this way. Therefore, this research is essential to elucidate the different rocks types and structures, with no or scarce previous research’s in this mountainous area. The main objective of this study is to selected rock type, rocky structures and different sizes of river sediments transported by rivers discharge from the previous geological periods. There are different types of sediments, terrace remnants, rocks and geological structures which are generally consist of Limestone and Gneiss, where the limestone is likely belonging to the Thythes ocean remnants in Afghanistan and contains Ammonites fossils. In some parts volcanic breccias, it shows the old volcanic eruptions, Stalactite and stalagmite Carbonitic sediments related to limestones are also present there. In addition, there are different types of geological structures such as Anticline, Syncline, dyke, Sill, Apophysis, Graben and Horst. Unconformities and horizontal layers related to Khengal and Cottagay series passing from this area are located one by another.展开更多
The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and p...The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst.展开更多
The main purpose of this research article is to evaluate the structural styles and hydrocarbon potential of Miano Block using seismic and well log data. The Miano Block discovered in 1993 is located in the Central Ind...The main purpose of this research article is to evaluate the structural styles and hydrocarbon potential of Miano Block using seismic and well log data. The Miano Block discovered in 1993 is located in the Central Indus Basin which is a part of an extensional regime exhibiting normal faulting, formed as a result of split of the Indian Plate firstly from Africa and then from Madagascar and Seychelles. Tectonically, the Miano Block lies on the Panno-Aqil graben between two extensive regional highs i.e. Jacobabad-Khairpur High and Mari Kandhkot High. Four migrated seismic lines were used for structural enhancement;P2092-111, P2092-113 and P2092-115 (dip lines) and P2092-110 (strike line). Time and depth contours were generated for four horizons, HabibRahi Formation, Sui Main Limestone, Ranikot Formation and Lower Goru Formation which showed the presence of horst and graben structures in the subsurface. The interpretation of horst and graben structures is based on a parallel set of NS-oriented high-angle planar normal faults with dips either towards SE or SW with majority of the faults dipping towards the SW. The faults are observed to exhibit slight disruption of strata with limited displacement to the order of about 50 m in Lower Goru Formation. Thus, horst and graben structures with NS trend in the study area are interpreted. The NS trend of these structures along with similar structural dip is inconsistent to the NW-SE orientation of regional structures i.e. Panno- Aqil graben and the Jacobabad-Kharipur and Mari-Kandhkot Highs indicating about the presence of a second minor set of faults and complexity of deformation. In this setting, Maino-02 well was drilled with the primary target as B-Sands of Lower Goru Formation belonging to Lower Cretaceous age while secondary target was A-Sands of Lower Goru belonging to the same age. The result of the petrophysical analysis supports two potential zones (zone 1 and zone 2) within the Lower Goru Formation. Potential reservoir zones were marked with average hydrocarbon satu展开更多
The Elkon Horst is a geological structure that consists of heterogeneous strata with highly variable geocryological and temperature conditions. Gaining accurate knowledge of permafrost distribution patterns within thi...The Elkon Horst is a geological structure that consists of heterogeneous strata with highly variable geocryological and temperature conditions. Gaining accurate knowledge of permafrost distribution patterns within this structure is of both scientific and practical importance. In mountainous terrain, the ground thermal regime is controlled by both surface and subsurface conditions. Surface conditions include snow cover characteristics, the presence or absence of vegetation, vegetation density, etc.. In contrast, subsurface conditions involve rock lithology or petrography, density, quantity and depth of fissures, groundwater, etc.. This article examines ground thermal regimes in various geomorphological settings based on temperature measurement data from geotechnical boreholes. The occurrence and extent of permafrost were evaluated for the entire horst area using direct and indirect methods. The maximum permafrost thickness measured in the Elkon Horst is 330 m, and the estimated maximum is 450 m at higher elevations. Thermophysical properties were determined for the major rock types, and the geothermal heat flux was estimated for the study area. The thermal conductivities were found to vary from 1.47 to 4.20 W/(m·K), and the dry bulk densities to range between 2,236 kg/m~3 and 3,235 kg/m~3. The average geothermal heat flux was estimated to be 44 mW/m~2.展开更多
文摘Tangi Mahi-par is a fault valley from previews geological period (Pleistocene) where the Kabul basin was a lake and occupied by water, and after the formation of Tangi Mahi-par fault valley, water was drained from this way. Therefore, this research is essential to elucidate the different rocks types and structures, with no or scarce previous research’s in this mountainous area. The main objective of this study is to selected rock type, rocky structures and different sizes of river sediments transported by rivers discharge from the previous geological periods. There are different types of sediments, terrace remnants, rocks and geological structures which are generally consist of Limestone and Gneiss, where the limestone is likely belonging to the Thythes ocean remnants in Afghanistan and contains Ammonites fossils. In some parts volcanic breccias, it shows the old volcanic eruptions, Stalactite and stalagmite Carbonitic sediments related to limestones are also present there. In addition, there are different types of geological structures such as Anticline, Syncline, dyke, Sill, Apophysis, Graben and Horst. Unconformities and horizontal layers related to Khengal and Cottagay series passing from this area are located one by another.
文摘The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst.
文摘The main purpose of this research article is to evaluate the structural styles and hydrocarbon potential of Miano Block using seismic and well log data. The Miano Block discovered in 1993 is located in the Central Indus Basin which is a part of an extensional regime exhibiting normal faulting, formed as a result of split of the Indian Plate firstly from Africa and then from Madagascar and Seychelles. Tectonically, the Miano Block lies on the Panno-Aqil graben between two extensive regional highs i.e. Jacobabad-Khairpur High and Mari Kandhkot High. Four migrated seismic lines were used for structural enhancement;P2092-111, P2092-113 and P2092-115 (dip lines) and P2092-110 (strike line). Time and depth contours were generated for four horizons, HabibRahi Formation, Sui Main Limestone, Ranikot Formation and Lower Goru Formation which showed the presence of horst and graben structures in the subsurface. The interpretation of horst and graben structures is based on a parallel set of NS-oriented high-angle planar normal faults with dips either towards SE or SW with majority of the faults dipping towards the SW. The faults are observed to exhibit slight disruption of strata with limited displacement to the order of about 50 m in Lower Goru Formation. Thus, horst and graben structures with NS trend in the study area are interpreted. The NS trend of these structures along with similar structural dip is inconsistent to the NW-SE orientation of regional structures i.e. Panno- Aqil graben and the Jacobabad-Kharipur and Mari-Kandhkot Highs indicating about the presence of a second minor set of faults and complexity of deformation. In this setting, Maino-02 well was drilled with the primary target as B-Sands of Lower Goru Formation belonging to Lower Cretaceous age while secondary target was A-Sands of Lower Goru belonging to the same age. The result of the petrophysical analysis supports two potential zones (zone 1 and zone 2) within the Lower Goru Formation. Potential reservoir zones were marked with average hydrocarbon satu
基金part of the Siberian Branch, Russian Academy of Sciences under project IX.135.2.1."Geo-Temperature Field and Transformation of the Permafrost Zone of North Asia and the Mountainous Regions of Central Asia"financial support from the RFBR (No.18-55-53041, No.20-55-53036)Natural Science Foundation of China (No.41811530089)。
文摘The Elkon Horst is a geological structure that consists of heterogeneous strata with highly variable geocryological and temperature conditions. Gaining accurate knowledge of permafrost distribution patterns within this structure is of both scientific and practical importance. In mountainous terrain, the ground thermal regime is controlled by both surface and subsurface conditions. Surface conditions include snow cover characteristics, the presence or absence of vegetation, vegetation density, etc.. In contrast, subsurface conditions involve rock lithology or petrography, density, quantity and depth of fissures, groundwater, etc.. This article examines ground thermal regimes in various geomorphological settings based on temperature measurement data from geotechnical boreholes. The occurrence and extent of permafrost were evaluated for the entire horst area using direct and indirect methods. The maximum permafrost thickness measured in the Elkon Horst is 330 m, and the estimated maximum is 450 m at higher elevations. Thermophysical properties were determined for the major rock types, and the geothermal heat flux was estimated for the study area. The thermal conductivities were found to vary from 1.47 to 4.20 W/(m·K), and the dry bulk densities to range between 2,236 kg/m~3 and 3,235 kg/m~3. The average geothermal heat flux was estimated to be 44 mW/m~2.
