松辽盆地后五家户气田沉积相特征与控气作用

本文对松辽盆地东南部后五家户气田划分出22种沉积微相,建立7种相层序,分析了扇三角洲及三角洲沉积环境对天然气成藏的控制作用。指出了扇三角洲前缘砂体和三角洲前缘砂体较为发育,沉积物源来自气田东北部和东南部两个方向。后五家户气田多为构造—岩性气藏和岩性气藏。     

板块下的构造及地幔动力学

最新的全球地幔地震层析资料揭示了岩石圈板片可以俯冲到核幔边界，超地幔羽可以从核幔边界上升到地壳上部形成热点。在大陆板块汇聚边界，地幔地震层析图像不仅显示了岩石圈板片的超深俯冲，还保存了拆沉的岩石圈“化石”残片的重要信息。从地幔深部所获取的新资料为全地幔“单层对流“的新模式提供了依据。在介绍上述全球构造研究新动向的基础上，本文强调了研究岩石圈板块必须了解板块下的构造，探索岩石圈板块的驱动力应该从“岩石圈动力学”升华到“地幔动力学”，并提出了大陆板块汇聚边界地幔动力学研究的新思考。     

Analysis of Karst Tufa from Guangxi, China

The paper presents an analysis of characteristic karst tufa from Guangxi, China, which has not been studied before. A comparison with tufa from Dinaric Karst of Croatia is discussed in view of the C-type climate. The major mineral is calcite. Minor minerals are quartz and dolomite, depending on location. The content of calcium carbonate varies from 65% to 92%, and that of magnesium carbonate from 0.03% to 1.77%. Among other elements, the most abundant are Fe, from 0.02% to 1.50%, and Ti, from 0.15% to 0.27%. Many other trace elements (V, Cr, Mn, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Hg and Pb) are also present. Specific activity of radionuclides 40K, 232Th, 137Cs, 226Ra and 238U varies from sample to sample. Concentration of U in tufa is close to that reported for sedimentary carbonate. Low concentration of 137Cs indicates that this part of the world was not exposed to nuclear explosions. The concentration of 226Ra is the highest in Mashan County. The ratio 238U/226Ra (0.21-0.71) in tufa from Mashan Co     

探地雷达检测中如何计算速度

雷达波的传播速度随介质而变,这给准确定位探测目标带来了一些困难,因为目标深度取决于速度与讯号反射时间的乘积.但另一方面,利用速度变化与介质的关系,反过来可以推断介质的物质架构.作者结合实用例举了7种求速度的方法,以供使用探地雷达的同行们选用.     

1303年山西洪洞8级大地震研究综述

叙述了1967年至2002年间国内有关研究1303年山西洪洞8级大地震的进展情况。综合叙述了有关这次地震的地震参数、地震破坏、地震断层、地震形变遗迹、地震发生的新构造与深部构造等。     

数字化气氡观测干扰因素的分析研究

在进行地下流体数字化气氡观测及将观测资料应用于震情分析的过程中 ,发现某些干扰因素对数字化气氡观测和水氡的影响不同。在目前所用观测仪器和方法的条件下 ,气温对气氡值的影响系数为 - 0 4 % /℃ ;气压对气氡测值的影响系数为 0 1% /hPa ;不同类型的气水分离装置对气氡观测的影响很显著 ;同一含水层的井 (泉 )出水量的短期变化可引起观测水井流量的变化 ,但对气氡测值影响不显著 ;气氡测值对逸出气流量的变化反映不明显 ;逸出气含有杂质及气路泄漏等均会引起测值的下降。结合仪器的工作原理 ,对干扰产生的机制以及排除的方法进行了讨论     

Absence of Archean basement in the South Kunlun Block: Nd-Sr-O isotopic evidence from granitoids

Abstract   The West Kunlun mountain range along the northwestern margin of the Tibetan Plateau is crucial in understanding the early tectonic history of the region. It can be divided into the North and South Kunlun Blocks, of which the former is considered to be part of the Tarim Craton, whereas consensus was not reached on the nature and origin of the South Kunlun Block. Samples were collected from the 471 Ma Yirba Pluton, the 405 Ma North Kudi Pluton and the 214 Ma Arkarz Shan Intrusive Complex. These granitoids cover approximately 60% of the Kudi area in the South Kunlun Block. Sr, Nd, and O isotope compositions preclude significant involvement of mantle-derived magma in the genesis of these granitoids; therefore, they can be used to decipher the nature of lower–mid crust in the area. All samples give Mesoproterozoic Nd model ages (1.1–1.5 Ga) similar to those of the exposed metamorphic complex of this block but significantly different from those of the basement of the North Kunlun Block (2.8 Ga). This indicates that the South Kunlun Block does not have an Archean basement, and, thus, does not support the microcontinent model that suggests the South Kunlun Block was a microcontinent once separated from and later collided back with the North Kunlun Block.     

Evolution and inheritance of a rock coast: western Galicia,northwestern Spain

There is increasing evidence that shore platforms and other elements of rock coasts may be inherited, at least in part, from interglacial stages when sea level was similar to today's. Most of this evidence, which includes ancient beaches and datable terrestrial deposits, has been obtained from areas of resistant, slowly eroding rock, where the platforms often appear to be much too wide to have developed since the sea reached its present level. It is much more dif?cult to demonstrate that inheritance has occurred in areas of weaker rock, which generally lack any datable material. The coast of western Galicia in northwestern Spain has shore platforms in igneous and metamorphic rocks that were deeply weathered during the Tertiary. These platforms are closely associated with ancient beaches from the last interglacial stage, and associated periglacial and ?uvio‐nival deposits that covered and fossilized most of the Eemian platforms and cliffs during the late middle and late Weichselian glacial stage. The sedimentary processes and the thickness and facies of the sediments were determined by the height, aspect and gradient of the coastal mountains, and their distance from the coast. Radiocarbon dating, sedimentary analysis and platform morphology indicate that the shore platforms of Galicia have been inherited from at least the last interglacial stage. They were fossilized in places beneath thick Weichselian deposits and then exhumed during the Holocene transgression. The abundant evidence for inheritance in Galicia has important implications for other coasts in fairly weak rocks where such evidence is generally lacking. Copyright © 2003 John Wiley & Sons, Ltd.     

缺少控制点的卫星遥感对地目标定位

从单线阵推扫式传感器的成像机理出发，利用6个卫星轨道开普勒参数和3个传感器姿态角建立了推扫式卫星遥感影像坐标与其地面点在地心坐标系下的坐标关系式，即构像方程。按照所建立的构像方程，对某地区一景SPOT-5影像进行对地目标定位，获得了实地上83．392m的平面精度；利用单个地面控制点对卫星轨道开普勒参数和传感器姿态实施调整后，目标定位精度提高到14．217m。试验证实，所建立的构像方程是正确的,在卫星遥感对地目标定位中有较好的应用前景。     

新疆某水利枢纽工程软弱结构面抗剪强度参数的试验研究

某水利枢纽工程位于伊犁地区,影响工程的主要问题为坝基岩体软弱结构面和断层的抗滑稳定问题。根据工程实际条件和软弱夹层特性,采取现场断层软弱结构面试验和室内模拟试验相结合,获得软弱夹层的抗剪参数。实践证明,把两种方法结合起来的试验成果可靠,尤其对一些不具备进行现场大型岩体软弱夹层抗剪试验的工程,采用室内中型直剪仪进 行剪切试验具有实用意义。