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671.
LCR-G型重力仪仪器参数的时变特征 总被引:6,自引:5,他引:1
采用区域适定法对LCR-G型重力仪的仪器参数进行适时标定。对标定结果的分析表明:(1)区域适定法标定结果与基线标定结果精度相当;(2)重力仪的线性项参数呈现随时间的趋势性下降和非线性。采用区域适定解校正后的线性项参数处理区域重力网的观测资料,不仅能有效地削弱系统误差,而且可提高重力仪检测地震信息的能力。 相似文献
672.
673.
CTS-1甚宽频带地震计 总被引:12,自引:6,他引:6
新建国家数字地震台网所使用的CTS-1甚宽频带地震计是一种具有甚宽频带、大动态范围、高灵敏度负反馈地震计。介绍了地震计的系统组成及工作原理。用多种方式给出了系统的传递函数,描述了仪器设计要点和系统测试,对仪器工作环境给予了特别的注意。最后简要介绍了地震计的应用情况。 相似文献
674.
伽师地震与区域断层活动研究 总被引:1,自引:1,他引:0
利用GPS、连续倾斜和地震活动性资料分析了伽师地区构造活动的特点和伽师强震群的动力背景,结果表明:在印度洋板块的挤压下,塔里木盆地的右旋腑冲运动是造成南天山区地震活动的主要原因;1996年3月19日伽师阿图什6.7级地震,强烈地影响了该地区块体由向西南倾斜转向北向倾斜,并可能成为诱伽师地区强震群活动的主要动力因素,利用1998年和1999年对该地区GPS测量的结果,给出了该地区断层活动的水平。 相似文献
675.
用大地测量数据反演2001年昆仑山地震 总被引:14,自引:12,他引:2
利用GPS和水准测量数据 ,采用模拟退火算法与分段断裂位错模型 ,对 2 0 0 1年昆仑山Ms8.1地震同震位错进行了反演研究。结果表明 :断层总长 390 (km)左右 ,呈直立走滑型 ,各断裂段左旋走滑量最大为 5~ 6m ,反演结果基本反映了地震破裂的总体特征 ;该地区岩石剪切模量 μ约为 4 .3× 10 10 Pa ;GPS和水准测量数据的联合使得多个参数的同时反演易于实现 ;大地测量数据与野外地质考察结果基本符合 相似文献
676.
南秦岭新生代安康月河盆地是北西向石泉-安康-竹山-房县左旋走滑断裂构造带西北端弯月状拉分盆地,论述了该盆地的边界断裂,盆地结构和三代盆地发育演化特征,估算了盆地最大扩张量(1.45km)和主控边界断裂的走滑位错量(2.9km),分析了盆地主要储能结构秘地震的关系。 相似文献
677.
LAN Kai YAN Taining. Drilling Engineering Technology Institute Zhongyuan Petroleum Exploration Bureau Puyang Henan China . Engineering Faculty China University of Geosciences Wuhan China 《东北亚地学研究》2009,(3):174-178
Drilling fluid is a common flushing medium used in pile foundation, geological drilling and petroleum drilling. Study on ultrasonic propagation properties in drilling fluid is of vital importance, not only for developing equipments to non-contact measuring concrete casting level for bored pile, but also for developing equip- ments considering drilling fluid as signal channel. The existence of clay particles makes the ultrasonic propagation and attenuation in drilling fluid much different from pure water. In order to know the relation among ultrasound frequency, slun-y density and depth, a series of laboratory experiments about ultrasound propagation in water-based bentonite slurry were finished. Wavelet method was adopted to process the gained original waves of ultrasonic propagation in slurry, so we knew the velocity and attenuation coefficient of ultrasound propagated in different drilling fluids with different density. The first group experiments shows that with density of drilling fluid increase, ultrasonic velocity will decrease but attenuation coefficient will increase if ultrasonic frequency keep constant. The second group experiments shows that the power of ultrasound will intensify in small bore hole, the attenuation coefficient is much smaller than theoretical value. 相似文献
678.
A New Arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Early Cambrian Guanshan Fauna, Kunming, China 总被引:2,自引:2,他引:0
LUO Huilin FU Xiaoping HU Shixue LI Yong HOU Shuguang YOU Ting PANG Jiyuan LIU Qi 《《地质学报》英文版》2007,81(1):1-7
The Guanshan Fauna is a soft-bodied fauna dominated by arthropods (including trilobites, trilobitoides, Tuzoia, Isoxys, and bradorids) in association with priapulids, brachiopods, anomalocaridids, vetulicoliids, sponges, chancellorids, and echinoderms. This paper reports and describes a new arthropod from the yellowish green mudstone at the lower part of the Wulongqing Formation, Canglangpuan Stage, Lower Cambrian in Kunming, Yunnan, China. The stratigraphic and geographic distribution, classification, fossil preservation, life style of this new arthropod and comparisons with other fossil arthropods are also discussed in details. The discovery and research of the non-mineralized arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Guanshan Fauna adds new members to the taxonomic list and provides new information to the evolution of early arthropods. Furthermore, this study would shed new light into the "Cambrian Explosion" and the evolution of early life. 相似文献
679.
Geochemistry and Modes of Occurrence of Hazardous Trace Elements in the No. 11 Coal Seam, Antaibao Surface Mine, Shanxi Province 总被引:1,自引:0,他引:1
SONG Dangyu QIN Yong WANG Wenfeng ZHANG Junying ZHENG Chuguang 《《地质学报》英文版》2007,81(1):135-140
Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis (INAA), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Cold-Vapor Atomic Absorption Spectrometry (CV-AAS) and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that: (a) the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; (b) the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; (c) the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; (d) the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that: (a) pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; (b) Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; (c) U, Zn, V, Na, P maybe controlled by phosphate or halite; (d) Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor. 相似文献
680.
MO Jinyou ZHAO Zhongru WANG Wei XU Xing 《《地质学报》英文版》2007,81(4):550-554
A new hadrosaurid dinosaur,Nanningosaurus dashiensis gen.et sp.nov.,is described based on an incomplete skeleton from the Late Cretaceous red beds of the Nalong Basin,Guangxi,southern China.Diagnostic features for the new taxon include the presence of a tall and sharply peaked dorsal process of the maxilla with reduced process of the jugai and a distinct lacrimal facet,gracile humerus with low,rounded deltopectoral crest,mandibular condyle of the quadrate transversly broad with reduced paraquadrate notch,dentary tooth with sinuous median carina and subsidiary ridge,relatively few tooth positions,ischial shaft straight along most of its distance,but to curve dorsally and expand at the distal end before the ischial foot begins.Phylogenetic analysis suggests that Nanningosaurus dashiensis is a basal member of Lambeosanrinae. 相似文献