The Canglangpu Stage of Lower Cambrian Series is widely distributed along both sides of the Tanlu (Tancheng-Lujiang) Fault Zone in the Jiao-Liao-Xu-Huai regions. In the Liaodong Peninsula, the Canglangpu Stage consist...The Canglangpu Stage of Lower Cambrian Series is widely distributed along both sides of the Tanlu (Tancheng-Lujiang) Fault Zone in the Jiao-Liao-Xu-Huai regions. In the Liaodong Peninsula, the Canglangpu Stage consists of three formations, i.e. Gejiatun, Dalinzi and Jianchang formations in ascending order (lying on the eastern side of the Tanlu Fault Zone). The Dalinzi Formation, developing in a littoral Sabkha environment, is full of catastrophic event records of violent seism, such as liquefied muddy-sandy veins, hydroplastic folds, hydroplastic micro-faults (three forming an organic whole), liquefied crinkled deformations, liquefied breccia and sandy dikes. Based on such records, the seismic liquified sequence of argillaceous rocks in Sabkha is built up. In northern Jiangsu and Anhui provinces, however, there hardly observe seismic records in the Canglangpu Stage, which consists of Jinshanzhai and lower Gouhou and upper Gouhou formations (lying on the western side of the Tanlu Fault Zone). Even if the Gouhou Formation, developing in a lagoon-dry environment, is in the same climate zone as the Dalinzi Formation, and 4 depositional sequences have been identified in the Canglangpu Stage in Northern Jiangsu and Anhui provinces, however, in the same stage in the Liaodong Peninsula, there exist only 3 ones. Therefore, it is not supported by the above mentioned evidence (such as catastrophic events, sequences stratigraphy and lithologic correlation of formations) that the Canglangpu Stage in the Liaodong Peninsula came from northern Jiangsu and Anhui provinces through a long-distance, about hundreds kilometers, left-hand displacement of the Tanlu Fault in the Mesozoic era.展开更多
Improvement of properties of weak soils in terms of strength,durability and cost is the key from engineering point of view.The weak soils could be stabilized using mechanical and/or chemical methods.Agents added durin...Improvement of properties of weak soils in terms of strength,durability and cost is the key from engineering point of view.The weak soils could be stabilized using mechanical and/or chemical methods.Agents added during chemical stabilization could improve the engineering properties of treated soils.Stabilizers utilized have to satisfy noticeable performance,durability,low price,and can be easily implemented.Since cement kiln dust(CKD) is industrial by-product,it would be a noble task if this waste material could be utilized for stabilization of sabkha soil.This study investigates the feasibility of utilizing CKD for improving the properties of sabkha soil.Soil samples are prepared with 2% cement and 10%,20% or 30% CKD and are tested to determine their unconfined compressive strength(UCS),soaked California bearing ratio(CBR) and durability.Mechanism of stabilization is studied utilizing advanced techniques,such as the scanning electron microscope(SEM),energy dispersive X-ray analysis(EDX),backscattered electron image(BEI) and X-ray diffraction analysis(XRD).It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid pavements.The incorporation of CKD leads to technical and economic benefits.展开更多
The State of Kuwait is located in the northwestern Arabian Gulf. It is characterized by arid to semi-arid weather. This study’s concerned with the southern coastal area of the Al-Khiran. The purpose of this study is ...The State of Kuwait is located in the northwestern Arabian Gulf. It is characterized by arid to semi-arid weather. This study’s concerned with the southern coastal area of the Al-Khiran. The purpose of this study is to evaluate and study the geo-history and evolution of geomorphologic features, especially coastal Ridges and Sabkhas in the Al-Khiran study area. This study based on the field observations as well as the application of Geographic Information Systems (GIS) and Remote Sensing techniques to establish a geodatabase for the study area in different disciplines. The results showed that the Al-Khiran coastal area was affected by the sea level fluctuation and coastal sedimentation during the Holocene and late Pleistocene. The coastal Ridges were originally coastal dunes, which were composed during the sea regression periods and consolidated with time. These Ridges were developed with time and separated the Al-Khiran area as a closed lagoon. This lagoon dried with time and formed a Sabkha field, especially on the depression zone that intersected or surrounded with the coastal Ridges. The Remote Sensing change detection technique shows that the changes were mainly concentrated on covering Sabkhas in some locations and might be due to the impact of active sand sheets and Aeolian sands. Land development in the Al-Khiran area led to the demolition of most of the coastal Ridges and Sabkha deposits.展开更多
Eight surface sabkha soils samples were collected from Ismailia—Suez roadbed, southwestern of Suez Canal district. Sedimentological and mineralogical analyses were conducted using grain size;X-ray diffraction and Sca...Eight surface sabkha soils samples were collected from Ismailia—Suez roadbed, southwestern of Suez Canal district. Sedimentological and mineralogical analyses were conducted using grain size;X-ray diffraction and Scanning Electron Microscopy (SEM). Grain size analysis indicates high contents of fine sand and mud as well as presence of salts. X-ray diffraction;Scanning Electron Microscopy (SEM) and EDAX tool clarified that the sabkha soils are enriched by quartz, sulfate minerals (gypsum, anhydrite), carbonate minerals (calcite-dolomite-aragonite), chlorides (halite and bischofite), and clay minerals. The results elucidate that the appearance of sabkha deposits and their distribution in the study area are controlled mainly by the content of water soluble salts through parent materials;ground water table;subsurface structural;and physiographic features for instance surface relief or topography;and human activity.展开更多
Kuwait is considered one of the desert regions of the Arabian Peninsula, that subjected to geomorphological processes forming the earth’s surface features. The anthropogenic activities through urbanization affected t...Kuwait is considered one of the desert regions of the Arabian Peninsula, that subjected to geomorphological processes forming the earth’s surface features. The anthropogenic activities through urbanization affected the earth geomorphology in the southern coastal sabkhas of Kuwait such as (Al-Jailiaha, Az-Zor and Al-Khiran). This study aims to monitor the geomorphological changes on the southern coastal sabkhas due to the urbanization expansion. Geographic information systems (GIS) and remote sensing (RS) techniques were used to study these changes, determine the areas of the coastal sabkhas in the southern part of Kuwait, following the developments, and identifying land cover in the area and its coastal strip including tourist resorts, sand dunes, and smooth sand sheets. The satellite images used in this study based on the data of Landsat-5 (TM) 1985, and Landsat-5 (TM) 1990, Landsat-7 (ETM+) 2001, visuals Landsat-8 (OLI) 2016 covering the years of (1985, 1990, 2001, 2016), in order to detect changes in the sabkhas and the extension of urbanization in the region. Digital Maps were made to show how extent the study area was affected by urbanization. Urbanization mostly expanded to the south in the study area on the account of the coastal sabkhas, where the area of the coastal sabkhas in 1985 was about 103.1 km2 and in 1990 it was about 84.1 km2. This led to the shrinking of the sabkhas area and extension of the resort area within the areas of sabkhas and sand dunes, particularly in Al-Khiran coastal area exposing it to the problem of sand drift and sand encroachment, which resulted in changes of the characteristics of the sabkhas, shrinkage of their area, and adverse impacts on their geomorphology.展开更多
The cultural and geomorphological heritages in Playas as a key address to find out past fluctuations called geotop. Iran is strategically located on an important trade route (Silk Road) between four cradles of civil...The cultural and geomorphological heritages in Playas as a key address to find out past fluctuations called geotop. Iran is strategically located on an important trade route (Silk Road) between four cradles of civilization namely, Babylon, Mesopotamia, Indus and Yangtze (Chinese). Iran is grafting point of four human civilizations which creates Persian civilization about 4,000 years ago. The Lut Desert and Dasht-e Kavir located the central and eastern Iran have been focal points for human settlements since 7,000 years ago. The geoarcheological findings on the Siyalk hills of Kashan located in the Dasht-e Kavir and Jiroft region located in the Lut desert are confirmations for human settlement since more than 7,000 years ago. Shorehzar that is a Persian equivalent word for Arabic word of Sabkha is considered as a Playa geomorphic type which involves precious evidences of quaternary fluctuations. In this article, geomorphological and paleoenvironmental investigations are integrated to provide a framework of environmental change for the late Pleistocene and early-mid Holocene periods in the main deserts of Iran, Lut. In this article based on main geotops of Lut, the quaternary evolutions have been discussed. The investigations are showing that Playas were bed of civilization in Iran Deserts.展开更多
基金The work was jointly supported by the State Science and Technology Commission of China (Grant No. 95-special-04) the Geological Bureau of Survey and CAGS (Grant Nos. DKD2001007 and DKD2001010).
文摘The Canglangpu Stage of Lower Cambrian Series is widely distributed along both sides of the Tanlu (Tancheng-Lujiang) Fault Zone in the Jiao-Liao-Xu-Huai regions. In the Liaodong Peninsula, the Canglangpu Stage consists of three formations, i.e. Gejiatun, Dalinzi and Jianchang formations in ascending order (lying on the eastern side of the Tanlu Fault Zone). The Dalinzi Formation, developing in a littoral Sabkha environment, is full of catastrophic event records of violent seism, such as liquefied muddy-sandy veins, hydroplastic folds, hydroplastic micro-faults (three forming an organic whole), liquefied crinkled deformations, liquefied breccia and sandy dikes. Based on such records, the seismic liquified sequence of argillaceous rocks in Sabkha is built up. In northern Jiangsu and Anhui provinces, however, there hardly observe seismic records in the Canglangpu Stage, which consists of Jinshanzhai and lower Gouhou and upper Gouhou formations (lying on the western side of the Tanlu Fault Zone). Even if the Gouhou Formation, developing in a lagoon-dry environment, is in the same climate zone as the Dalinzi Formation, and 4 depositional sequences have been identified in the Canglangpu Stage in Northern Jiangsu and Anhui provinces, however, in the same stage in the Liaodong Peninsula, there exist only 3 ones. Therefore, it is not supported by the above mentioned evidence (such as catastrophic events, sequences stratigraphy and lithologic correlation of formations) that the Canglangpu Stage in the Liaodong Peninsula came from northern Jiangsu and Anhui provinces through a long-distance, about hundreds kilometers, left-hand displacement of the Tanlu Fault in the Mesozoic era.
文摘Improvement of properties of weak soils in terms of strength,durability and cost is the key from engineering point of view.The weak soils could be stabilized using mechanical and/or chemical methods.Agents added during chemical stabilization could improve the engineering properties of treated soils.Stabilizers utilized have to satisfy noticeable performance,durability,low price,and can be easily implemented.Since cement kiln dust(CKD) is industrial by-product,it would be a noble task if this waste material could be utilized for stabilization of sabkha soil.This study investigates the feasibility of utilizing CKD for improving the properties of sabkha soil.Soil samples are prepared with 2% cement and 10%,20% or 30% CKD and are tested to determine their unconfined compressive strength(UCS),soaked California bearing ratio(CBR) and durability.Mechanism of stabilization is studied utilizing advanced techniques,such as the scanning electron microscope(SEM),energy dispersive X-ray analysis(EDX),backscattered electron image(BEI) and X-ray diffraction analysis(XRD).It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid pavements.The incorporation of CKD leads to technical and economic benefits.
文摘The State of Kuwait is located in the northwestern Arabian Gulf. It is characterized by arid to semi-arid weather. This study’s concerned with the southern coastal area of the Al-Khiran. The purpose of this study is to evaluate and study the geo-history and evolution of geomorphologic features, especially coastal Ridges and Sabkhas in the Al-Khiran study area. This study based on the field observations as well as the application of Geographic Information Systems (GIS) and Remote Sensing techniques to establish a geodatabase for the study area in different disciplines. The results showed that the Al-Khiran coastal area was affected by the sea level fluctuation and coastal sedimentation during the Holocene and late Pleistocene. The coastal Ridges were originally coastal dunes, which were composed during the sea regression periods and consolidated with time. These Ridges were developed with time and separated the Al-Khiran area as a closed lagoon. This lagoon dried with time and formed a Sabkha field, especially on the depression zone that intersected or surrounded with the coastal Ridges. The Remote Sensing change detection technique shows that the changes were mainly concentrated on covering Sabkhas in some locations and might be due to the impact of active sand sheets and Aeolian sands. Land development in the Al-Khiran area led to the demolition of most of the coastal Ridges and Sabkha deposits.
文摘Eight surface sabkha soils samples were collected from Ismailia—Suez roadbed, southwestern of Suez Canal district. Sedimentological and mineralogical analyses were conducted using grain size;X-ray diffraction and Scanning Electron Microscopy (SEM). Grain size analysis indicates high contents of fine sand and mud as well as presence of salts. X-ray diffraction;Scanning Electron Microscopy (SEM) and EDAX tool clarified that the sabkha soils are enriched by quartz, sulfate minerals (gypsum, anhydrite), carbonate minerals (calcite-dolomite-aragonite), chlorides (halite and bischofite), and clay minerals. The results elucidate that the appearance of sabkha deposits and their distribution in the study area are controlled mainly by the content of water soluble salts through parent materials;ground water table;subsurface structural;and physiographic features for instance surface relief or topography;and human activity.
文摘Kuwait is considered one of the desert regions of the Arabian Peninsula, that subjected to geomorphological processes forming the earth’s surface features. The anthropogenic activities through urbanization affected the earth geomorphology in the southern coastal sabkhas of Kuwait such as (Al-Jailiaha, Az-Zor and Al-Khiran). This study aims to monitor the geomorphological changes on the southern coastal sabkhas due to the urbanization expansion. Geographic information systems (GIS) and remote sensing (RS) techniques were used to study these changes, determine the areas of the coastal sabkhas in the southern part of Kuwait, following the developments, and identifying land cover in the area and its coastal strip including tourist resorts, sand dunes, and smooth sand sheets. The satellite images used in this study based on the data of Landsat-5 (TM) 1985, and Landsat-5 (TM) 1990, Landsat-7 (ETM+) 2001, visuals Landsat-8 (OLI) 2016 covering the years of (1985, 1990, 2001, 2016), in order to detect changes in the sabkhas and the extension of urbanization in the region. Digital Maps were made to show how extent the study area was affected by urbanization. Urbanization mostly expanded to the south in the study area on the account of the coastal sabkhas, where the area of the coastal sabkhas in 1985 was about 103.1 km2 and in 1990 it was about 84.1 km2. This led to the shrinking of the sabkhas area and extension of the resort area within the areas of sabkhas and sand dunes, particularly in Al-Khiran coastal area exposing it to the problem of sand drift and sand encroachment, which resulted in changes of the characteristics of the sabkhas, shrinkage of their area, and adverse impacts on their geomorphology.
文摘The cultural and geomorphological heritages in Playas as a key address to find out past fluctuations called geotop. Iran is strategically located on an important trade route (Silk Road) between four cradles of civilization namely, Babylon, Mesopotamia, Indus and Yangtze (Chinese). Iran is grafting point of four human civilizations which creates Persian civilization about 4,000 years ago. The Lut Desert and Dasht-e Kavir located the central and eastern Iran have been focal points for human settlements since 7,000 years ago. The geoarcheological findings on the Siyalk hills of Kashan located in the Dasht-e Kavir and Jiroft region located in the Lut desert are confirmations for human settlement since more than 7,000 years ago. Shorehzar that is a Persian equivalent word for Arabic word of Sabkha is considered as a Playa geomorphic type which involves precious evidences of quaternary fluctuations. In this article, geomorphological and paleoenvironmental investigations are integrated to provide a framework of environmental change for the late Pleistocene and early-mid Holocene periods in the main deserts of Iran, Lut. In this article based on main geotops of Lut, the quaternary evolutions have been discussed. The investigations are showing that Playas were bed of civilization in Iran Deserts.