河北尚义侏罗系后城组节理研究

研究区侏罗系后城组地层发育着多组节理,根据其方位及相互关系,自早到晚分为５个节理组,其定向分别为１７４°、７７°、５８°、１４５°和１１９°,反映出节理形成的最大主压应力方向交替变化和偏转。岩石应变强度具有由弱至强,再由强至弱的演化趋势,而节理型式趋向不规则。区内节理多属构造成因,推测形成于侏罗纪末至白垩纪初近南北向的区域挤压过程。热液活动在区内节理形成之后,而后１１９°方位节理组发生右行走滑。     

上海陆域地区古河道溺谷相沉积层工程地质特征研究

上海地区全新世沉积物在区域上分异剧烈,由此,研究区内形成主要的古河道有四条。按其沉积相的层序组合可划分出三个基本类型,每个类型和古河道溺上各层序组合,反映了一种沉积环境和沉积过程。同时,它们的工程地质特征亦各自不同。本文对三个基本类型的古河道溺谷相沉积的桩基持力层的选择,应用找到了充分的依据。     

江西变质基底类型及变质地层的划分对比

根据近期区调、科研的新资料,将江西省北、中、中南部的变质基底划分为江南型、混杂型和华南型三类,并对变质地层层序与时代进行了划分对比。     

Analysis of Error Caused by Replacing Spherical Shell with an Elastic Plate Model in Studying Bending Deformation of the Lithosphere

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强震孕育与断层形变异常形态及时空分布特征

分析了华北北部20世纪70年代初以来的断层形变资料。结果表明：震前断层活动存在明显的阶段性特征；短临阶段断层形变异常主要形态有两种：一种是在α、β相后的γ相短临异常，这种异常一般在近源区出现；另一种是较大幅度的突跳型短临异常，这种异常一般在远源区出现，这些都是断层形变前兆由中期过渡到短期的明显标志；断层形变短临异常有从外围向震中迁移的特征；唐山地震前出现γ相短临异常的比例高于大同和张北地震，主要表现为在中期趋势积累背景上的反向；3次强震前α、β、γ相异常场地的分布具构造控制特征；强震前场地断层异常活动存在象限性分布特征，且与震源机制解的结果基本一致。     

青藏高原东北缘断层活动变形的模拟研究

分析和讨论了位错理论模型的发展历史和应用领域，采用走滑和倾滑位错理论模型对青藏高原东北缘的多组断层活动产生的三维形变场进行了数值模拟研究，并将数值模拟结果与该地区1999～2001年间的GPS观测结果进行了对比分析。得出了甘青块体顺时针转动等一些较重要的结论和认识。     

Response of saturated and nearly saturated porous media: Different formulations and their applicability

The response of saturated porous medium is of significant interest in many fields ranging from geomechanics to biomechanics. Biot was the first to formulate the basic equations governing the process of coupled flow and deformation in porous media. Depending on the nature of loading vis‐à‐vis the characteristics of the media, different formulations (fully dynamic, partly dynamic, quasi‐static) are possible. In this study, analytical solutions are developed for the response of saturated and nearly saturated porous media under plane strain condition. The solutions for different formulations are developed in terms of non‐dimensional parameters. The response is studied for various conditions and the regions of validity for various formulations are identified in a parametric space. An assessment of the needed formulation for few important problems is also presented. Copyright © 2008 John Wiley & Sons, Ltd.     

颗粒流沉积边程中的同沉积冲刷变形构造

济阳拗陷坨147井沙三段岩心的颗粒流沉积中．存在一系列特殊的同沉积期变形构造。包括：颗粒流向下侵蚀。并沿纹层面挤入到下伏油页岩层中．形成伸长状的小砂体；砂楔上部的泥页岩薄层在后续流体的冲刷下向后翻卷变形；翻卷片被撕裂、断开混入到颗粒流中。并被流体拖曳变形；变形体被继续拖曳形成脉状分叉的拖曳痕。上述几种现象可以构成一个连续的变化序列，与油页岩的薄互层和颗粒流的流体是形成上述连续变形构造的重要条件。对这种现象的研究．有助于进一步了解重力流的冲刷、沉积过程。     

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Dehydration-related deformation during regional metamorphism, NW Sardinia, Italy

The relationship between deformation and dehydration has been investigated in Hercynian regionally metamorphosed rocks exposed on NW Sardinia. Two episodes of prograde mineral growth (M₁ & M₂) involving dehydration are recognized: growth of chlorite/phengite porphyroblasts at anchizone metamorphic conditions, contemporaneous with the first phase of deformation, D₁, and growth of biotite from chlorite and phengite coincident with the second phase of deformation, D₂. Deformation during both episodes of dehydration is characterized by penetrative axial planar foliations defined by well-developed phyllosilicate preferred orientations quantified by XRD textural goniometry, tight to isoclinal similar folds (interlimb angles <40°), and mineral-filled veins (hydrofractures) orientated parallel to axial planar foliations, that formed contemporaneously with the development of the penetrative foliations. No prograde mineral growth occurred during D₂ at chlorite-zone conditions. D₂ deformation in the absence of dehydration is characterized by non-penetrative crenulation cleavages, poorly developed phyllosilicate preferred orientations, relatively open (interlimb angles >40°), low-strain similar folds and minor brittle deformation. Systematic variations in macrofold interlimb angles, with respect to the timing of mineral growth, indicate that enhanced shortening (c. 80%) occurred during dehydration. Microfabrics show that the onset of dehydration is associated with the transition from a crenulation cleavage to a penetrative foliation. The presence of axial planar hydrofractures that formed coevally with dehydration and fabric development requires that supralithostatic fluid pressures and low differential stresses (<c. 20 MPa) accompanied dehydration. These features demonstrate a connection between the timing of dehydration and the style of deformation.