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991.
992.
酷暑来临,对于长期伏案工作、久坐于桌前抑或工作压力过大、各种应酬中烟酒过量繁忙的男性领导者而言,存在着严重的健康隐患——前列腺炎。本栏目特在夏季酷暑前列腺炎高发期,呼吁男性朋友们更多关注自己的身心健康,能以饱满的精神与健康的体魄攀登事业的高峰,拥有家庭的幸福! 相似文献
993.
营口-潍坊断裂带新生代运动学特征 总被引:6,自引:0,他引:6
姜建平 《海洋地质与第四纪地质》2008,28(4)
营口-潍坊断裂带在新生代时期对渤海湾盆地东部构造、沉积及油气成藏规律等方面具有重要影响和控制作用.依据大量实际地震资料,从剖面上识别出了花状构造、丝带效应、反转构造等营口-潍坊断裂带新生代时期走滑活动的标志,在平面上识别出了4种组合构造样式,在此基础上,应用拉分盆地走滑量计算的理论模型,对营口-潍坊断裂带新生代时期的走滑位移量进行了初步估算,认为营口-潍坊断裂带在新生代时期具右旋走滑活动特征,其主要走滑活动表现为3期,分别为始新世早期、渐新世早-中期和上新世晚期-第四纪,新生代累计右旋走滑位移量约为10~20 km. 相似文献
994.
综合运用高精度层序地层学、构造一地层学方法,认为十屋断陷深层发育的各类隐蔽圈闭是下一步勘探工作的重要目标。同时,由于构造对沉积的控制作用,在断陷内部不同的构造部位具有不同的隐蔽圈闭分布特征。十屋断陷西部皮家地区、北部张家屯一八屋地区位于油气主要运移指向区,分别由断裂坡折带和以挠曲型褶皱为特征的弯折带控制的储集砂体十分发育,盖层及保存条件也十分优越,是深部原生岩性、地层油气藏最有利的勘探目标区带。 相似文献
995.
针对遥感多光谱影像处理,提出一种立足于多尺度像斑模型,应用数据挖掘中的特征构造来实现跨尺度特征构造的方法,将最佳尺度选择问题隐含在特征构造中,而不直接进行最佳尺度选择.从而在区分地物方面更加准确,分类精度更高. 相似文献
996.
On tectonic movement in the South China Sea during the Cenozoic 总被引:1,自引:1,他引:0
The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and MidOligocene, during Mid and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and IndoAustralia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and IndoAustralia plates. 相似文献
997.
This paper discusses the numerical prediction of the induced pressure and lift of the planing surfaces in a steady motion based on the potential flow solver as well as the spray drag by use of the practical method.The numerical method for computation of the induced pressure and lift is potential-based boundary element method.Special technique is identified to present upwash geometry and to determine the spray drag.Numerical results of a planing flat plate and planing craft model 4666 are presented.It is shown that the method is robust and efficient and the results agree well with the experimental measurements with various Froude humors. 相似文献
998.
Based on a synthesis of zircon inheritance from Mesozoic igneous rocks in the eastern portion of the North China Craton (NCC) , it is proposed that inherited zircons with Neoproterozoie ages identified from these rocks are of a heterogenous derivation from the Yangtze/South China block, rather than from the NCC itself. The mechanism that introduces these zircons incorporated into the NCC is likely by tectonic underplating during the Triassic continental subduction of the Yangtze block beneath the NCC. Tectonic addition of abundant crustal materials represented by the heterogenous zircons into the NCC, probably along Moho or weak interfaces within the NCC's crust, led to the crustal thickening in the NCC. These heterogenous materials, either as (partial) source rocks or as contaminants of the magmas generated during an extension environment following the crustal thickening, were reworked and therefore have significant contribution to petrogenesis of the Mesozoic igneous rocks. The crustal thickening resulted from the tectonic underplating, as indicated by the distribution extent of the heterogenous zircons, is spatially similar to that of the lithospheric thinning, with both mainly occurring in the eastern segment of the NCC. This is probably suggestive of an intrinsic relation between the thickening and thinning events during the Mesozoic evolution of the NCC. 相似文献
999.
探索热液矿床成矿作用的方向性,是勘查矿床和寻找盲矿体时,一个迫切需要解决的研究课题.早在20世纪80年代,中国地矿界便面临寻找隐伏矿、半隐伏矿的挑战,就需要开展"区域成矿作用方向性的理论找矿",以已知预测未知. 相似文献
1000.
HUANG Yulong WANG Pujun CHEN Shuming .College of Earth Sciences Jilin University Changchun China.Daqing Oilfield Corporation PetroChina Daqing Heilongjiang China 《东北亚地学研究》2009,12(2):64-79
About forty productive oil/gas fields hosted in volcanic reservoirs have been found since 1957 in fourteen basins of China. They can be simply subdivided into two groups, the east and the west. Reservoir volcanic rocks of the east group are predominantly composed of Late Jurassic to Early Cretaceous rhyolite and Tertiary basalt, preferred being considered as rift type volcanics developed in the circum-Pacific tectonic regime. Those of the west are Permo-Carboniferous intermediate/basic volcanic rocks, being island-arc type ones developed in paleo-Asian Ocean tectonic regime. 相似文献