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161.
乌鲁木齐西山断层新构造运动特征 总被引:4,自引:0,他引:4
展布于哈萨克斯坦—准噶尔亚板块南缘西山南麓的乌鲁木齐西山断层,构造地貌发育,航卫片上线性影象清晰,呈舒缓波状。断面倾向NWW,倾角60°~83°。破碎带宽约100m,内含多个断面,构成叠瓦状构造,逆冲量颇大。在走向近NE区段有一定左行走滑活动分量。新构造运动使侏罗系逆冲到中更新统之上,断层断错了全新统的冲积层。由中强地震沿西山断层分布资料显示,现今仍为粘滑活动。经14C测年确定,最近两次明显粘滑活动时间为4759a和493a,其时间间隔为4266a,其中一个断面的逆冲量分别为1.0m和0.25m。 相似文献
162.
鹅公山火山盆地受郯庐断裂系影响,NW断裂构造尤为特色:张扭性,倾向NE,右行下滑,对盆地中3个铀矿床及绝大多数铀矿(化)点具明显控制作用,是铀矿成矿的关键要素。研究NW断裂对在鹅公山火山盆地及其它地区找矿都具有实际意义。 相似文献
163.
作者在野外数学中发现,棒锤山人工露头上存在一条重要的纵向断层,经研究认为、棒锤山纵向断层反映了汤-仑推覆体在其发展中至少存在两次明显的应力释放过程,它可能与两次大的构造推覆及应力集中有关。 相似文献
164.
165.
煤田地震勘探一直探寻着对小断层的自动检测方法,因受各种因素的影响,至今尚无良策。本文介绍了多元地震参数的模式识别方法,并通过模型及实测资料成功地检测到10m以下小断层。 相似文献
166.
本文依据1:5万区调资料,扼要介绍了武宁陆相红盆填图单位的拟定、表示方法及工作原理的应用,重点叙述了红盆内多个冲积扇体特征及其之间的叠覆关系,阐明了盆缘断裂是控制红盆成生、发展演化的主导因素。对红盆成生及演化、时代也作了初步探讨。 相似文献
167.
The incidence of lung cancer in the Gejiu area of Yunnan Province ranks the first in the world.The radon level(indoor,soil) was measured in the Gejiu area by the SSNTD method from 1990 to 1996,The result indicates an extensive high-level of indoor radon in that area though U and Th are lower in local limestones,The indoor radon level of houses located in the geologic fault zone is 6 times high that 2km far from the fault zone.The reason probably is that the radon level of soil in the fault is 6-8 times high that 1 km far from the faults.our data indicate that a lower range of radon levels,0-100Bq.m^-3,exists in healthy families.However,a higher radon level,over 800 Bq.m^-3,is often found corresponding to that of cancer patients‘ homes(the house-owners are suffering from either lung cancer or leukaemia or liver cancer),Obviously,an increase in lung cancer incidence follows an increase in indoor radon level,The risk of cancer induced by indoor radon is no longer an inference,but a fact. 相似文献
168.
甘肃桦树沟(铁)铜矿床的成因机制 总被引:4,自引:0,他引:4
矿床地质地球化学特征研究结果表明,随着古陆边缘弧-槽-盆体系的发生与发展,元古代基底火山(沉积)岩系经深循环水(海水)-热系统的作用,成矿物质被浸出和搬运,并经海底喷溢作用沉淀于海盆洼地中形成桦树沟矿床含铜建造,后期变质作用使成矿物质活化、转移和富集。桦树沟矿床为喷气(流)沉积-变质改造型(铁)铜矿床。 相似文献
169.
By contrasting and analyzing the characteristics of gravity field nearby some important active faults in the continent of
China, it can be found that the crust blocks where Bouguer anomalies are regionally positive (or relatively positive) are
moving towards the terrestrial poles and the blocks where Bouguer anomalies in a tremendous area are negative (or relatively
negative) are moving towards the equator. By analysis of mechanics and mathematics calculation and based on lots of practical
data, the authors hold that the change in density of a crust block is a decisive factor that causes the horizontal movement
of the continental crust, while magma activity is an important factor that leads to the change in density of a crust block. 相似文献
170.
Song-Yan Song Xue-Song Zhou Chun-Yong Wang Xian-Kang Zhang Jian-Li Song Yi Gong 《地震学报(英文版)》1997,10(1):15-25
On the basis of S wave information from Tai’an-Xinzhou DSS profile and with reference to the results from P-wave interpretation,
the 2-D structures, including S-wave velocity V
s, ratio γ between V
p and V
s; and Poisson’ s ratio σ, are calculated; the structural configuration of the profile is presented and the relevant inferences are drawn from the
above results. Upwarping mantle districts (V
s≈4.30 km/s) and sloping mantle districts (V
s≈4.50 km/s) of the profile with velocity difference about −4% at the top of upper mantle are divided according to the differences
of V
s, γ and σ in different media and structures, also with reference to the information of their neighbouring regions; the existence of
Niujiaqiao-Dongwang high-angle ultra-crustal fault zone is reaffirmed; the properties of low and high velocity blocks (zones)
including the crust-mantle transitionalzone and the boudary indicators of North China rift valley are discussed. A comprehensive
study is conducted on the relation of the interpretation results with earthquakes. It is concluded that the mantle upwarps,
thermal material upwells through the high-angle fault, the primary hypocenter was located at the crust-mantle juncture 30.0∼33.0
km deep, and additional stress excited the M
S=6.8 and M
S=7.2 earthquakes at specific locations around 9.0 km below Niujiaqiao-Dongwang, the earthquakes took place around the high-angle
ultra-crustal fault and centered in the brittle media and rock strata with low γ and low σ values.
This subject is part of the 85-907-02 key project during the “8th Five-Year Plan” from the State Science and Technology Commission. 相似文献