青藏高原西部地质灾害分布特征及背景分析

青藏高原的快速隆起使其地质、地貌和气候发生了剧烈变化,导致崩塌、滑坡、泥石流、岩屑流和冰湖溃坝等地质灾害频发。利用遥感技术对青藏高原西部地质灾害的分布、形成条件进行了研究,对灾害形成的背景进行了探讨。崩塌、滑坡和泥石流主要发育于喜马拉雅山、冈底斯山、喀喇昆仑山及昆仑山的高山峡谷之中; 冰湖一般分布于雪线附近; 岩屑流发育在雪线之下基岩裸露区的陡坡上; 融冻泥流则位于海拔更低的多年冻土和季节性冻土的过渡地带。高原内部的造山带为灾害提供了地形条件; 冰川和大气降水为灾害提供了水源; 冰川作用和频繁的融冻作用为灾害提供了物源。青藏高原的快速隆升是地质灾害发育的内因,高海拔高寒气候是灾害发育的外因。     

浅谈GIS与环境应用模型集成应用的可行性

地理信息系统(GIS)的应用功能及应用领域,GIS与环境科学的应用集成,具有广泛的发展前景。本文着重介绍了环境应用模型及其特点,分析了GIS与环境应用模型集成的可行性和优势。     

波动方程CT技术在地震数据处理中的应用

本文从畸变的Born近似的微扰技术出发,给出了利用广义Radon变换和Fourier积分算子的理论反演介质间断性的原理.将声学的广义Radon变换与经典Radon变换进行类比,近似地导出了声学广义Radon变换的反演公式. 本文对于反射地震学的情况,提出了一种拟线性化方法,考虑了成象点的一次散射场,从某种程度上减少了Born近似对弱散射的苛求. 利用同一模型的理论记录和物理实验记录的反演计算结果对提出的方法进行了验证,并讨论了进一步提高成象精度的方法.     

The Jinchuan Ultramafic Intrusion: Cumulate of a High-Mg Basaltic Magma

The Jinchuan intrusion, situated in Gansu province, China, isan ultramafic dyke-like body emplaced in the Longshoushan upliftedterrain on the southwest margin of the Sino-Korea platform.The intrusion is 6 km long, 350 m wide and hosts a major Ni-Cusulfide deposit. It comprises three subchambers: the west, west-central,and east. The two western subchambers are narrow and deep, andboth are laterally zoned from dunite in the core through Iherzoliteto olivine pyroxenite toward the margins. The eastern subchamberis shallow and wide, and it shows vertical stratification gradingfrom dunite at the base upward into Iherzolite and plagioclaseIherzolite, then back to Iherzolite at the top. Sixty rock samples from the Jinchuan intrusion have been analyzedfor major and trace elements, and 54 samples were also analyzedfor the REE. All samples contain > 24 wt.% MgO, with themajority having > 35% when recalculated to 100% anhydrous.Negative linear correlations are observed between MgO and mostother constituents (except for a few such as Na₂O, K₂O, Sr,and Rb, which may have been affected by alteration), and itappears that the rocks were essentially formed as mixtures ofcumulus olivine and primary magma. Electron microprobe analyses show olivine compositions fromFo₇₉ to Fo₈₆, with most between Fo₈₃ and Fo₈₅. The MgO/(MgO+ FeO) value of the primary magma is calculated to have been 0.64, and its MgO content is estimated to have been 12 wt.%.Thus, the Jinchuan igneous body is probably the ultramafic cumulateportion of an intrusion of a high-magnesium basaltic magma relatedto continental rifting. We suggest that the two western subchambers of the Jinchuanintrusion represent the main conduit to the original magma chamberand that their zoning was formed by flow differentiation. Theeastern subchamber probably represents a higher level of themagma chamber, where crystallization was marked by convectionand periodic replenishment. After consolidation, the Jinchuanintrusion was tilted to the east so the deeper parts of thewestern subchambers are now exposed to the same erosion levelas the shallower part of the eastern subchamber.     

The application of ultrasonic seismic model experiment in quality test of cement mortar injection of Yongjiang river submarine tun－nel tube foundation

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POSTGLACIAL TRANSGRESSION AND REGRESSION AND BARRIER-LAGOON SEDIMENTARY SYSTEM

Barrier-lagoon system as one of the important sedimentary units is widely distributed in the coastal zone of China. Along with the postglacial transgression and regression they have been continuously formed and developed with migration of the coastline. This article deals with the formation, distribution, developing direction and criteria for recognition of the barrier-lagoon sedimentary systems, which can be classified into transgressive, regressive and stable ones in China. Based on the examples of barrier-lagoon systems along the coastal zone of China, some views about these systems in foreign literatures are discussed and commented.     

THE WIND FIELD IN TROPICAL EASTERLY DISTURBANCE

It is expounded in this paper that the wind is weak in a zone of large curvature and strong in the small one in case of large scale stream field in the tropics. The relation between the variation of stream fields and generation of cyclones in tropical disturbance are also studied based on the authors' another paper.     

原油物性演化规律新发现及其对页岩油勘探的启示

针对烃源岩生成的原油物性随热演化如何变化的问题,本文基于对准噶尔盆地玛湖凹陷下二叠统风城组和吉木萨尔凹陷中二叠统芦草沟组下段源储紧邻自生自储页岩油物性、地化特征、成藏特征及原油物性与烃源岩热演化关系的分析,综合烃源岩生烃热模拟实验结果与国内外相关文献资料,首次确认了咸化湖相烃源岩生成的原油物性与烃源岩热演化程度之间的变化规律。认为页岩油源岩生成的原油密度和黏度具有随热演化程度增强先增加而后降低的规律,其中生油高峰附近生成的原油非烃相对含量、密度和黏度最高。该认识不仅是对已有的石油地质学中原油物性随热演化规律认识的进一步厘定和修正,而且对页岩油甜点段、甜点区的选择以及页岩油原位转化等都有极为重要和现实的指导作用。     

重力式幕墙加预应力锚杆及钻孔小桩组合基坑支护体系

采用重力式幕墙加预应力锚杆及钻孔小桩组合基坑支护体系 ,方法简单 ,既节省投资 ,又可保证工期 ,且止水效果相当好。     

辽南太古宙古陆壳构造变形及演化

由早期绿岩、变质ＴＴＧ杂岩及闪长岩为主构成的辽南古陆壳,在新太古宙末期—古元古代初期遭受了四期构造变形,以主期变形（第三期）最为显著。该期变形重塑了古陆壳上的太古宙岩石,形成密集而普遍的区域透入性主期片麻理（Ｓ３）,矿物线理（Ｌ３）及“顺片”掩卧褶皱（ｆ３）,并伴随高温低压条件下的角闪岩相区域变质作用,变形机制属中构造环境下由南至北的韧性水平剪切滑脱,其动力学成因可能为诱发古元古代辽东裂谷的地幔软流圈热羽的早期活动,导致辽南古陆块上部硅铝壳相对于壳下岩石圈作反向滑脱的壳下拆离作用。