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1.
新西兰是南太平洋上现代构造运动十分强烈的地区,活断层遍布全国,自1840年以来,曾发生过17次M≥7.0级的地震。然而新西兰各个地区所表现的活断层规模、性质和活动强度有很大差别。文中介绍了各地区活断层的规模,晚第四纪以来地壳水平和垂直运动速率,地热流,均衡重力异常,莫霍界面波速等具体数据以资对比,分析了各地区现代构造运动性质和地壳介质的地球物理性质,从而将新西兰划分为六个现代构造地区。根据新西兰1960年—1980年约1000多次M≥4.5级仪器地震记录和历史地震讨论了新西兰六个区地震活动强度频度和活动类型的区域特征。  相似文献   

2.
应新西兰国家研究科技部邀请,以国家地震局人事教育司司长李裕彻为团长的中国地震代表团于1993年10月10-20日访问考察了新西兰。本文介绍了这次访问考察的概况,并根据访问期间了解到的情况,较详细地介绍了新西兰的防震减灾工作、防灾减灾机构及其职能、防震减灾研究等方面的情况。  相似文献   

3.
新西兰地区地震活动时空分布的多重分形特征研究   总被引:4,自引:1,他引:4       下载免费PDF全文
利用多重分形维数谱估计的Hill方法,讨论了新西兰地震活动区地震活动的震源分布、震中分布以及时间间隔分布的多重分形特征.结果表明,该地区浅源地震的震中分布和震源分布在给定不同的起始震级的条件下均具有明显的丛集特征;对于中、深源地震这种特征不甚明显.而地震活动时间间隔分布则无论对于浅源和中、深源地震均呈单重分形的性质,但具有分形性质的尺度范围有较大的差别.这些结果表明,浅源地震与中、深源地震的活动特征显著不同.   相似文献   

4.
ABSTRACT

Increased surface water runoff from about 3000 km2 of land converted to pasture from native forest and scrub, mostly in the last 20 years, in the central North Island of New Zealand has caused gully erosion. The causes of increased runoff were investigated by using 20 runoff plots and collecting data over a two-year period on climatic, soil, vegetation and runoff variables for 44 storms. Statistical analysis has shown that: runoff from pasture is greater than that from scrub or ungrazed grass; most of the intense runoff can be explained by intense rainfalls occuring on previously dry areas; 63 per cent of the runoff can be explained statistically in terms of three variables. Land use practices should be designed to reduce soil moisture depletion and to inhibit peak storm runoff, especially during intense summer rainstorms.  相似文献   

5.
The surface ruptures produced by the 2016 MW7.8 Karkoura earthquake, New Zealand are distributed in a belt with~170km long and~35km wide, trending generally in the NE-SW direction. There are at least 12 faults on which meter-scale displacements are identified and they were formed across two distinct seismotectonic provinces with fundamental different characteristics(Hamling et al., 2017; Litchfield et al., 2017). Although the trending directions of the seismic surface ruptures vary greatly at different locations, the ruptured faults can be generally divided into two groups with the NE to NEE direction and the NNW to N direction, respectively. The faults in the NNW-near NS direction are nearly parallel with 40~50km apart and featured by reverse movement with the maximum displacement of 5~6m. The faults in the NE-NNE direction, with the maximum of 25~30km apart are not continuous and featured by the dextral strike slip with the largest displacement of 10~12m. Even if some faults along the NE-NEE direction are end to end connected, their strikes differ by about 30°. The combination styles of the strike-slip fault surface ruptures along the NE-NEE direction can be merged into 3 categories, including en-echelon, bifurcation and parallel patterns. The scales of the fault surface ruptures with the same structural style could be obviously different in different areas, which results in significant changes in the widths of deformation zone, from tens of meters to hundreds of meters. En-echelon distributed surface rupture(section)can appear as a combination belt of meter-scale to dozens of meter-scale shear fracture with bulge and compressional shear fractures, and also can be characterized by the combination of the left-step en-echelon tensile shear fractures with a length of more than one hundred meters. The step-overs between surface rupture sections are clearly different in sizes, which can be dozens of meters, hundreds of meters to several kilometers. The spacing between parallel surface ruptures can be several meters, dozens of meters to several kilometers. Besides, as one of the prominent characteristics, the seismic surface ruptures caused by the Karkoura earthquake broke through the known distribution pattern of active faults. The surface ruptures can occur either on the previously thought inactive or unmapped faults, or break through the distribution range of previously realized active faults in the striking or lateral direction. The basic features about the distribution and widths of the surface ruptures induced by the 2016 MW7.8 Karkoura earthquake, New Zealand presented in this paper might be helpful for understanding some seismic problems such as complex corresponding relationship between the active faults and the deep seismogenic structure, and the necessary measurements for engineering crossing active faults.  相似文献   

6.
新西兰北岛南部韦恩加瓦河地区在晚更新世冰缘气候控制下,由沉积和侵蚀的交替作用形成较高较老的阶地。较低较新的阶地是在全新世中期以来的现代正常气候条件下形成的。这些阶地分别被怀拉拉帕断层水平错动297米、100米,57米和28米。距今10000年以来,怀拉拉帕断层的平均水平滑动速度为10毫米/年。1855年8级地震的重复率为1500年  相似文献   

7.
超高压变质研究涉及的一个基本力学问题是为什么低密度的大陆地壳岩石能克服浮力俯冲到高密度地幔100多公里的深度.本文的三维有限单元法计算表明:俯冲海洋板块可以拖曳侧面相邻宽度不超过150km的一窄条大陆板块,俯冲到超高压变质深度,形成少见的大规模超高压变质带.十几公里乃至几十公里尺度的陆壳块体,可能被俯冲地幔裹挟至超高压变质深度,在造山带内形成零星出露的超高压变质岩.成熟的陆-陆碰撞带则不可能使陆壳俯冲到超高压变质深度.  相似文献   

8.
超高压变质研究涉及的一个基本力学问题是为什么低密度的大陆地壳岩石能克服浮力俯冲到高密度地幔100多公里的深度.本文的三维有限单元法计算表明:俯冲海洋板块可以拖曳侧面相邻宽度不超过150km的一窄条大陆板块,俯冲到超高压变质深度,形成少见的大规模超高压变质带.十几公里乃至几十公里尺度的陆壳块体,可能被俯冲地幔裹挟至超高压变质深度,在造山带内形成零星出露的超高压变质岩.成熟的陆-陆碰撞带则不可能使陆壳俯冲到超高压变质深度.  相似文献   

9.
通过分析认为乌鲁木齐地区的年降雨、年气温对新 0 4号井、新 1 0号井水位和新 1 0号泉流量没有明显干扰。新 0 4号井、新 1 0号井和新 1 0号泉的震兆特征是 0 4号井水位为负异常 ,1 0号井水位、1 0号泉流量为正异常 ,产生差异的原因可能与观测点所处的构造环境有关。预测了新疆及邻近地区未来一年或稍长一段时间内有发生 7级左右地震的可能。  相似文献   

10.
NEW BOOKS     
Marvin Saines 《Ground water》1976,14(5):344-344
  相似文献   

11.
12.
NEW BOOKS     
Marvin Saines 《Ground water》1981,19(2):235-235
  相似文献   

13.
NEW BOOKS     
Marvin Saines 《Ground water》1980,18(2):184-184
  相似文献   

14.
4. Hydraulics     
Abstract

A solid state event recorder and reader suitable for use with a tipping bucket raingauge are described. The recorder is a small battery operated unit with very low power consumption, capable of recording 64, 8 bit, words. The portable reader unit is used to interrogate it.  相似文献   

15.
兰陵  李新勇  夏爱国 《内陆地震》2004,18(4):382-384
在以往30多年曲地震地下流体水位观测中,我国地震地下流体分析预报人员积累了大量水位震例数据和不少宝贵经验,但这些震例和经验都是基于以往的模拟水位观测资料基础上的。如果观测方式进行了数字化改造,那么以往的震例经验还能否继续适用是一个值得探讨的问题。  相似文献   

16.
朱成英  崔勇  张涛 《内陆地震》2011,25(3):239-246
运用mapsis软件前兆异常分析中的差分、从属函数等计算方法对新10号泉硫化物测值进行异常识别。结果表明:(1)差分和从属函数异常以高值异常为主;(2)差分异常对应近场MS≥5地震对应率为100%(6/6),对远场MS≥7地震对应率为66.7%(4/6);(3)差分和从属函数异常最大量对近场MS≥5地震的震级和震中距相关性不明显;(4)差分和从属函数异常有一定同步性。  相似文献   

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19.
通过理论推导,提出了一种新的K-Ar、^40Ar-^39Ar等时线:^40Ar/^40K-^36Ar/^40K、^40Ar/^39Ar-^36Ar/^39Ar等时线。通过实例证明它与其它等时线方法可以进行相互检验。在一些不能利用其它等时线方法的情况下,新的^40Ar/^40K-^36Ar/^40K、^40Ar/^39Ar-^36Ar/^39Ar等时线方法可以充分显示它的使用价值和存在意义。  相似文献   

20.
一.地電阻儀所測量之數值地電阻探礦儀,簡稱地電阻儀,係物理探礦中測量地電阻率時所用之儀器。為欲觀察地下导電之情形,可將電流I,藉兩個電極C1,C2通入地下,再自另外兩個電極P1,P2  相似文献   

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