Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the dr...Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the drilling boreholes. The purpose of this study is to use field geophysics to calculate the depth of mineral reserve. The study area is located 38 km from Zarand city called Jalalabad iron mine. In this study, gravimetric data were measured and mineral depth was calculated using the Euler method. 1314 readings have been performed in this area. The rocks of the region include volcanic and sedimentary. The source of the mineralization in the area is hydrothermal processes. After gravity measuring in the region, the data were corrected, then various methods such as anomalous map remaining in levels one and two, upward expansion, first and second-degree vertical derivatives, analytical method, and analytical signal were drawn, and finally, the depth of the deposit was estimated by Euler method. As a result, the depth of the mineral deposit was calculated to be between 20 and 30 meters on average.展开更多
This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaskanear Banska Bystrica in Slovakia.The aim of the study is to demonstrate the impossibility ...This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaskanear Banska Bystrica in Slovakia.The aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic material.Its maximum thickness is 3 m.Another specificific condition of the study area is its location in the built-up area,due to which the applicability of geophysical methods was limited.The article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill,which complicates the identification of cave spaces.The recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined.展开更多
The Alborz Range,northern Iran,is a chain of mountains along the southern side of the Caspian Sea.This mountain range shows strong tectonic activity with several destructive earthquakes in the past.The range is tecton...The Alborz Range,northern Iran,is a chain of mountains along the southern side of the Caspian Sea.This mountain range shows strong tectonic activity with several destructive earthquakes in the past.The range is tectonically active,and the seismicity record shows both range-parallel left-lateral and thrust faulting.Tehran the capital of Iran and one of the largest cities in the world is located in the foothill of the Alborz Mountains,which is at risk of seismic hazard.This study is mainly focused on a scarp that passes by west of the Qarchak(a suburb in south east of Tehran)and therefore it is called the West Qarchak Fault.So,geological and geophysical surveying method was applied to study the West Qarchak Fault which is continuous and reaches to Pishva Fault in south east(with same trend)and crosses the Kahrizak Fault in the north west.In conclusion,it can be seen that apparently the geometry of the West Qarchak Fault is normal but the real mechanism is reverse(based on subsurface investigation).Morphologically,the Kahrizak Fault scarp has some similarity to the West Qarchak fault and it can be said that the geometry and mechanism of the Kahrizak Fault is same as the West Qarchak Fault,but requires a more detailed study.展开更多
One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-prec...One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-precession magnetometers for the mapping of magnetic anomalies</span><span style="font-family:Verdana;"> due to kimberlites. Three different magnetic maps are obtained from the result of total magnetic field data processing on Oásis Montaj software programme. These maps include magnetic anomaly maps through statistical analyses, total magnetic field intensity map and map of the analytic signal. Based on the interpretation of these maps a structure is identified with SWW-NEE directions in which magnetic signatures that indicate the presence of kimberlite pipes are observed. As the interpretation of the magnetic anomalies is a complicated process due to their dipolar nature, the analytic signal is generated, where is possible to observe the typical shape of these anomalies.</span>展开更多
Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate reservoirs.In the conditions of the field under consideration,th...Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate reservoirs.In the conditions of the field under consideration,the hydraulic fracturing leads to a significant differentiation of technological efficiency indicators,which makes it expedient to study the patterns of crack formation in detail.Studies were carried out for all wells,which were considered as the objects of impact,to assess the spatial orientation of the cracks formed.The developed indirect method was used for this purpose,the reliability of which was confirmed by geophysical methods.During the analysis,it was found that in all cases,the crack is oriented in the direction of the section of the development system element characterized by the maximum reservoir pressure.At the same time,the reservoir pressure values for all wells were determined at one point in time(at the beginning of HF)using machine learning methods.The reliability of the machine learning methods used is confirmed by the high convergence with the actual(historical)reservoir pressures obtained during hydrodynamic studies of wells.The obtained conclusion about the influence of the reservoir pressure on the patterns of fracture formation should be taken into account when planning hydraulic fracturing under the conditions studied.展开更多
文摘Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the drilling boreholes. The purpose of this study is to use field geophysics to calculate the depth of mineral reserve. The study area is located 38 km from Zarand city called Jalalabad iron mine. In this study, gravimetric data were measured and mineral depth was calculated using the Euler method. 1314 readings have been performed in this area. The rocks of the region include volcanic and sedimentary. The source of the mineralization in the area is hydrothermal processes. After gravity measuring in the region, the data were corrected, then various methods such as anomalous map remaining in levels one and two, upward expansion, first and second-degree vertical derivatives, analytical method, and analytical signal were drawn, and finally, the depth of the deposit was estimated by Euler method. As a result, the depth of the mineral deposit was calculated to be between 20 and 30 meters on average.
基金the support of the project(SP2017/22)which is the base of this articlepartially supported by the Slovak Research and Development Agency under contract No.APVV-0129-12the Scientific Grant Agency of the Ministry of Education,Science,Research and Sport of the Slovak Republic and the Slovak Academy of Sciences(VEGA)within the project No.1/0559/17 and APVV 1/0462/16。
文摘This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaskanear Banska Bystrica in Slovakia.The aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic material.Its maximum thickness is 3 m.Another specificific condition of the study area is its location in the built-up area,due to which the applicability of geophysical methods was limited.The article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill,which complicates the identification of cave spaces.The recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined.
文摘The Alborz Range,northern Iran,is a chain of mountains along the southern side of the Caspian Sea.This mountain range shows strong tectonic activity with several destructive earthquakes in the past.The range is tectonically active,and the seismicity record shows both range-parallel left-lateral and thrust faulting.Tehran the capital of Iran and one of the largest cities in the world is located in the foothill of the Alborz Mountains,which is at risk of seismic hazard.This study is mainly focused on a scarp that passes by west of the Qarchak(a suburb in south east of Tehran)and therefore it is called the West Qarchak Fault.So,geological and geophysical surveying method was applied to study the West Qarchak Fault which is continuous and reaches to Pishva Fault in south east(with same trend)and crosses the Kahrizak Fault in the north west.In conclusion,it can be seen that apparently the geometry of the West Qarchak Fault is normal but the real mechanism is reverse(based on subsurface investigation).Morphologically,the Kahrizak Fault scarp has some similarity to the West Qarchak fault and it can be said that the geometry and mechanism of the Kahrizak Fault is same as the West Qarchak Fault,but requires a more detailed study.
文摘One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-precession magnetometers for the mapping of magnetic anomalies</span><span style="font-family:Verdana;"> due to kimberlites. Three different magnetic maps are obtained from the result of total magnetic field data processing on Oásis Montaj software programme. These maps include magnetic anomaly maps through statistical analyses, total magnetic field intensity map and map of the analytic signal. Based on the interpretation of these maps a structure is identified with SWW-NEE directions in which magnetic signatures that indicate the presence of kimberlite pipes are observed. As the interpretation of the magnetic anomalies is a complicated process due to their dipolar nature, the analytic signal is generated, where is possible to observe the typical shape of these anomalies.</span>
文摘Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate reservoirs.In the conditions of the field under consideration,the hydraulic fracturing leads to a significant differentiation of technological efficiency indicators,which makes it expedient to study the patterns of crack formation in detail.Studies were carried out for all wells,which were considered as the objects of impact,to assess the spatial orientation of the cracks formed.The developed indirect method was used for this purpose,the reliability of which was confirmed by geophysical methods.During the analysis,it was found that in all cases,the crack is oriented in the direction of the section of the development system element characterized by the maximum reservoir pressure.At the same time,the reservoir pressure values for all wells were determined at one point in time(at the beginning of HF)using machine learning methods.The reliability of the machine learning methods used is confirmed by the high convergence with the actual(historical)reservoir pressures obtained during hydrodynamic studies of wells.The obtained conclusion about the influence of the reservoir pressure on the patterns of fracture formation should be taken into account when planning hydraulic fracturing under the conditions studied.
