Two near-vertical deep seismic reflection profiles (140km-long, 24-fold) were completed in the 1679 Sanhe-Pinggu earthquake (M8.0) region. The profiles ran through the Xiadian fault and the Ershilichangshan fault. The...Two near-vertical deep seismic reflection profiles (140km-long, 24-fold) were completed in the 1679 Sanhe-Pinggu earthquake (M8.0) region. The profiles ran through the Xiadian fault and the Ershilichangshan fault. The profiling result shows that the crust in this region is divided into the upper crust, the lower crust and the crust-mantle transitional zone by two powerful laminated reflectors: one at the two-way travel-time of about 7.0s (21km), the other at about 11.0~12.5s (33~37km). Crustal structure varies significantly in vertical direction. The shallow part is characterized by obvious stratification, multilayers and complexity. The upper crust on the whole features reflection “transparency”, while the lower crust features distinct reflectivity. Crustal structure also varies a lot in the lateral direction. The main fracture in this region is the deep fault under the Xiadian fault. This deep fault is steeply inclined (nearly vertical), and is supposed to be the causative fault of the Sanhe-Pinggu M8.0 earthquake. The two profiles respectively reveal the existence of local strong reflectivity in the lower crust and the lower part of the upper crust, which is assumed to be a dike or rock mass formed by the upwelling and cooling down of materials from the upper mantle. Magmatic activity in this part brought about differences in regional stress distribution, which then gave rise to the formation of the deep fault. That is supposed to be the deep structural setting for the Sanhe-Pinggu M8.0 earthquake.展开更多
The microphase separation extent of biomedical segmented polyetherurethanes were greatly enhanced due to the presence of sulfoalkyl pendant groups contained in the hard segments,and the hard segments were more orderly...The microphase separation extent of biomedical segmented polyetherurethanes were greatly enhanced due to the presence of sulfoalkyl pendant groups contained in the hard segments,and the hard segments were more orderly aggregated through ionic interaction.展开更多
ThiS work was one of the key State-funded projects for natural sciences during the period from 1988-1992 under the joint sponsorship of the CAS,the State Planning Commission,the Institute of Geography and the Yellow R...ThiS work was one of the key State-funded projects for natural sciences during the period from 1988-1992 under the joint sponsorship of the CAS,the State Planning Commission,the Institute of Geography and the Yellow River Harnessing Committee under the Ministry of Water Conservancy.The project involves some 140 scientists from 19 research units,such as institutes and universities.Its purpose is to make clear the vicissitudes of environmental evolution and water-and-soil changes in the Yel-展开更多
文摘Two near-vertical deep seismic reflection profiles (140km-long, 24-fold) were completed in the 1679 Sanhe-Pinggu earthquake (M8.0) region. The profiles ran through the Xiadian fault and the Ershilichangshan fault. The profiling result shows that the crust in this region is divided into the upper crust, the lower crust and the crust-mantle transitional zone by two powerful laminated reflectors: one at the two-way travel-time of about 7.0s (21km), the other at about 11.0~12.5s (33~37km). Crustal structure varies significantly in vertical direction. The shallow part is characterized by obvious stratification, multilayers and complexity. The upper crust on the whole features reflection “transparency”, while the lower crust features distinct reflectivity. Crustal structure also varies a lot in the lateral direction. The main fracture in this region is the deep fault under the Xiadian fault. This deep fault is steeply inclined (nearly vertical), and is supposed to be the causative fault of the Sanhe-Pinggu M8.0 earthquake. The two profiles respectively reveal the existence of local strong reflectivity in the lower crust and the lower part of the upper crust, which is assumed to be a dike or rock mass formed by the upwelling and cooling down of materials from the upper mantle. Magmatic activity in this part brought about differences in regional stress distribution, which then gave rise to the formation of the deep fault. That is supposed to be the deep structural setting for the Sanhe-Pinggu M8.0 earthquake.
文摘The microphase separation extent of biomedical segmented polyetherurethanes were greatly enhanced due to the presence of sulfoalkyl pendant groups contained in the hard segments,and the hard segments were more orderly aggregated through ionic interaction.
文摘ThiS work was one of the key State-funded projects for natural sciences during the period from 1988-1992 under the joint sponsorship of the CAS,the State Planning Commission,the Institute of Geography and the Yellow River Harnessing Committee under the Ministry of Water Conservancy.The project involves some 140 scientists from 19 research units,such as institutes and universities.Its purpose is to make clear the vicissitudes of environmental evolution and water-and-soil changes in the Yel-