三层倾斜电性层模型的电测深曲线反演

本文根据对三层倾斜电性层模型的电测深曲线反演结果,解释了地电台址的电测深曲线的复杂性,对如何较精确地确定各电性层的埋藏深度作了探讨。     

南黄海海域中生代前陆盆地形成的构造背景

南黄海盆地占据了下扬子板块的主体,自元古宙以来经历了多期构造运动,受到华北板块、扬子板块、华南板块、太平洋板块多个板块相互作用的影响,形成多期盆地演化阶段的叠合盆地。分析了南黄海盆地前人钻井资料及最新二维地震资料,并与下扬子苏北盆地地层及构造特征进行对比,认为整个下扬子区域受华北—扬子板块碰撞的影响,经历了中生代前陆盆地演化阶段。下扬子陆域部分地区发育相对完整的中生代沉积,记录了华北—扬子板块之间洋壳消减、陆陆碰撞、前陆盆地发育及碰撞后活动。而在下扬子对应海域延伸部分的南黄海盆地中,仅在盆地北部烟台坳陷东北缘通过钻井证实有侏罗纪前陆盆地地层,钻遇地层仅发育侏罗系上部陆相沉积,在地震剖面中可以解释出侏罗系下部海陆交互相地层,向上转变为陆相沉积地层。对比下扬子陆域与海域地层发育情况,华北—扬子板块碰撞造山过程对于下扬子整个区域的影响因地而异,在三叠纪末期—侏罗纪时期南黄海盆地内沉积缺失,南黄海海域区处于广泛抬升状态,印支运动期间地层挤压活动强烈,烟台坳陷内海相地层中逆冲断层广泛发育。在南黄海盆地东北缘,前陆盆地侏罗系地层发育于南倾边界断层的上盘,认为南黄海盆地侏罗纪前陆盆发育的构造背景受到同期北侧千里岩超高压变质带从深部折返影响,随着千里岩隆起带的快速抬升,为南黄海盆地北缘提供了沉积空间及物源,沉积了大套的侏罗系前陆盆地地层。     

折劈发育条件的分析——以鞍山附近元古宙地体之折劈(S2)为例

 本文以辽宁省鞍山附近元古宙千枚岩和片岩中的折劈S₂为论述的基础。按照简单剪切原理计算出发育折劈的岩石中的γ(剪应变)值。通过γ等值线图及断面图、T_M/T_QF-α相关图和变形标志(石英)形态比的研究,初步认为,折劈岩石中矿物组成、结构、微构造和α角等的明显“分异”现象,主要由剪应变和伴随发生的物质迁移所造成。有限应变状态的特点是:剪应变高的带(M)和剪应变较低的带(QF)相间排列。相邻带剪应变差异控制着扩散物质迁移机制,对微构造(如微褶皱)的生成,有重要作用。折劈生成于T低于500℃,P 约为5kb 左右的绿片岩相变质环境,它标志着地壳处于区域性抬升状态,相继产生的共轭折劈和膝折带(属于 D,构造),则表明已抬升到足以引起岩石总体体积扩张的高度。     

南极长城站潮间带丝藻和底栖硅藻色素组成和吸收光谱的分析

本文对 1 989年 2月采集长城站前高潮区岩石上附着的丝藻 ,以及在中潮区小石块和水沼边生长的底栖硅藻 ,进行吸收光谱分析、分离。鉴定出底栖硅藻的色素种类有 6种 ,它们分别是胡萝卜素、叶绿素 a、岩藻黄质、叶绿酸、新黄素、叶绿素 c。丝藻的色素种类有 9种 ,分别为胡萝卜素、脱镁叶绿素 a、叶绿素 a、叶绿素 b、叶绿酸、脱酯基叶绿酸、新黄素、叶绿素 c和脱镁叶绿素 c。潮间带底栖硅藻和丝藻有各自特定的吸收光谱 ,它们所含色素种类也有明显差异。藻类色素对不同波长光的吸收能力是不同的 ,因此可以利用吸收光谱来鉴定藻类的种类     

雪峰山区韧性剪切构造带

雪峰山区存在着三条与山脉步向一致的北东向弧形韧性剪切带(Fl、F_2、F_3),F_1以左旋剪切为主,F_2、F_3以右旋剪切为主,但均系同一次构造剪切力所致。由变形岩石中的旅转应变体估算出剪切中心地带的剪切应力值大约是7-8,有限应变沿X最大拉伸量195％,沿Z方向最大缩短量为62％。其深部韧性剪切发生于加里东构造期,这之后又遭受浅部脆性应变叠加而构成断裂构造综合实体。     

夏季对流和环流10-25天季内变化-5西太平洋暖池热力状况的关系

主要讨论了西太平洋暖池热力状况年际变化相联系的10－25天季内振荡的特征。在西太平洋暖池处于“暖”夏季和“冷”夏季两种状态时，10－25天季内振荡呈现出明显差异，在所讨论的亚洲－太平洋大部分区域，“暖”夏季时对流活动的10－25天季内变化和“冷”夏季时对流活动的10－25天季内变化表现出显的反相关关系，表明对流活动的年际变化与季内变化的相互作用。当西太平洋暖池上空对流活动的10－25天季内振荡处于最强和最弱阶段时，低层大气表现为Gill型环流响应，即气旋式（反气旋式）环流出现在最强（最弱）对流活动的西北，这种对流和环流关系在西太平洋暖池出于“暖”夏季和“冷”夏季两种状态时均成立。而当西太平洋暖池上空对流活动的10－25天季内振荡处于除此以外其他阶段时，就看不到Gill型环流响应。     

四川会理小青山铜矿床地球化学特征

小青山铜矿床产于中元古界会理群小青山组中，主矿体严格受地层层位控制。通过对主要类型岩矿石（矿物）的常量、微量元素、矿物包裹体成分、稀土元素分析及不同矿物的硫、铅同位素和矿物包裹体氢氧、碳同位素测试研究，认为该矿床具有沉积、变质作用，尤其是岩浆热液叠加改造作用的特征。     

Nonlinear local Lyapunov exponent and atmospheric predictability research

Because atmosphere itself is a nonlinear system and there exist some problems using the linearized equations to study the initial error growth, in this paper we try to use the error nonlinear growth theory to discuss its evolution, based on which we first put forward a new concept: nonlinear local Lyapunov exponent. It is quite different from the classic Lyapunov exponent because it may characterize the finite time error local average growth and its value depends on the initial condition, initial error, variables, evolution time, temporal and spatial scales. Based on its definition and the at-mospheric features, we provide a reasonable algorithm to the exponent for the experimental data, obtain the atmospheric initial error growth in finite time and gain the maximal prediction time. Lastly, taking 500 hPa height field as example, we discuss the application of the nonlinear local Lyapunov exponent in the study of atmospheric predictability and get some reliable results: atmospheric predictability has a distinct spatial structure. Overall, predictability shows a zonal distribution. Prediction time achieves the maximum over tropics, the second near the regions of Antarctic, it is also longer next to the Arctic and in subtropics and the mid-latitude the predictability is lowest. Particularly speaking, the average prediction time near the equation is 12 days and the maximum is located in the tropical Indian, Indonesia and the neighborhood, tropical eastern Pacific Ocean, on these regions the prediction time is about two weeks. Antarctic has a higher predictability than the neighboring latitudes and the prediction time is about 9 days. This feature is more obvious on Southern Hemispheric summer. In Arctic, the predictability is also higher than the one over mid-high latitudes but it is not pronounced as in Antarctic. Mid-high latitude of both Hemispheres (30°S―60°S, 30°―60°N) have the lowest predictability and the mean prediction time is just 3―4 d. In addition, predictability varies with the seasons. Most regions in the Northern Hemisphere, the predictability in winter is higher than that in summer, especially in the mid-high latitude: North Atlantic, North Pacific and Greenland Island. However in the Southern Hemisphere, near the Antarctic regions (60°S―90°S), the corresponding summer has higher predictability than its winter, while in other areas especially in the latitudes of 30°S―60°S, the prediction does not change obviously with the seasons and the average time is 3―5 d. Both the theoretical and data computation results show that nonlinear local Lyapunov exponent and the nonlinear local error growth really may measure the predictability of the atmospheric variables in different temporal and spatial scales.     

21世纪中国城市海洋灾害防御战略研究

我国有漫长的海岸线,沿海地区是我国经济发展最快的地区,但是海洋灾害的频繁发生及其造成的经济损失年均增长率的不断提高,已经成为制约我国海洋经济和沿海经济持续稳定发展的重要因素.基于海洋灾害的特殊性、海洋对社会发展与日俱增的重要性,对影响我国沿海地区的海洋灾害及其危害性进行了系统、详细的探讨,并根据我国对海洋灾害的防御能力提出了防灾减灾的战略措施.     

Experimental study on the influence of hydro-chemical erosion on morphology parameters and shear properties of limestone fractures

Acta Geotechnica - Hydro-chemical erosion has a great effect on the micro-structure morphology and macroscopic mechanical properties of the rock mass. In this paper, direct shear test system was...