云南剑川铁腊曲铅银矿矿床地质     

施建萍  陈新敏 《云南地质》2011,30(2):141-143

铁腊曲铅银矿位于德钦—维西有色金属成矿带内,是三江成矿带中铅、锌、银矿的富集区域之一。初步认为矿床成因受构造破碎带控制,与地下热卤水溶滤作用有关的热液型铅银多金属矿床。  相似文献   

保山腊西山铜铅锌多金属矿地质特征     

杨洪  胡成军  李泉  杨勇 《云南地质》2011,30(2):144-147

腊西山矿赋存在古生界崇山群变质岩系中,受区域性崇山西侧压扭性大断裂控制,矿(化)体分布于次级北西向断裂破碎带的矽卡岩碎裂岩内,矿化类型为矽卡岩型.  相似文献   

八寨火山角砾岩筒浅表难见金刚石原因分析     

杨昌毕  刘勇 《云南地质》2011,30(3):247-254

从岩筒地质特征、组成岩石和矿物的成因类型,对岩浆源区温压条件作出判断,并与含金刚石金伯利岩筒对比,认为该区火山角砾岩筒不完全具备金刚石成矿温压条件。  相似文献   

云南富宁里达锑矿地质及找矿前景     

亓春英  杨云保 《云南地质》2011,30(3):294-298

锑矿赋存于上寒武统博菜田组中段的硅质岩和硅化碳酸盐岩的层间破碎带中,矿化受区域上的北西向构造和地层所控制。深入研究,扩大资源和寻找新的资源基地。  相似文献   

青藏高原南部雅鲁藏布江蛇绿岩带的时空分布特征及地质意义   总被引：6，自引：0，他引：6  

张万平  袁四化  刘伟 《西北地质》2011,44(1):1-9

雅鲁藏布江缝合带是青藏高原上重要的缝合带之一,位于青藏高原南部,蛇绿岩是该带的主体。雅鲁藏布江缝合带按蛇绿岩的出露规模、岩石层序以及侵位时间,大致可以分为东段、中段和西段。在蛇绿岩出露规模上存在显著差异,东段规模较小,中段次之,西段最大,并且在西段分成两支蛇绿岩带;蛇绿岩岩石层序出露比较齐全的是中段日喀则和东段罗布莎,其他地方的蛇绿岩均被肢解,不能组成完整的蛇绿岩岩石剖面;在蛇绿岩的形成和侵位时间上,也有着不同的特点,东段和西段集中形成于晚侏罗世—早白垩世,而中段形成时间较早,时代从中三叠世一直持续到早白垩世,主要集中形成于晚侏罗世—早白垩世。笔者系统研究雅鲁藏布江缝合带蛇绿岩在东西方向上所表现出来的差异性,对更全面深刻地了解新特提斯洋的产生、俯冲及其消亡过程和演化历史具有重要意义。  相似文献   

早寒武世初期沂沭断裂带地震效应   总被引：1，自引：0，他引：1  

田洪水  张邦花  祝介旺  张增奇  李洪奎 《古地理学报》2011,13(6):645-656

早寒武世初期,随着从古沂沭海峡向西海侵的发展,鲁西地区沉积了厚度不等的主要由砂岩、泥岩和碳酸盐岩组成的滨海、潟湖及浅海相沉积,其层位属下寒武统底部的李官组和朱砂洞组.在它们沉积过程中,沂沭断裂带正发生着伴有频繁海底地震的构造裂陷活动,使海底沉积物在自沂沭断裂带向西200 km范围内产生了不同的地震效应,形成了各种地震成...  相似文献   

Three dimensional application of the complementary mild-slope equation     

Yaron Toledo  Yehuda Agnon 《Coastal Engineering》2011

The complementary mild-slope equation (CMSE) is a depth-integrated equation, which models refraction and diffraction of linear time-harmonic water waves. For 2D problems, it was shown to give better agreements with exact linear theory compared to other mild-slope (MS) type equations. However, no reference was given to 3D problems. In contrast to other MS-type models, the CMSE is derived in terms of a stream function vector rather than in terms of a velocity potential. For the 3D case, this complicates the governing equation and creates difficulties in formulating an adequate number of boundary conditions. In this paper, the CMSE is re-derived using Hamilton's principle from the Irrotational Green–Naghdi equations with a correction for the 3D case. A parabolic version of it is presented as well. The additional boundary conditions needed for 3D problems are constructed using the irrotationality condition. The CMSE is compared with an analytical solution and wave tank experiments for 3D problems. The results show very good agreement.  相似文献   

A Boussinesq-type wave driver for a morphodynamical model to predict short-term morphology     

Ivo Wenneker  Ap van Dongeren  Jamie Lescinski  Dano Roelvink  Mart Borsboom 《Coastal Engineering》2011

The prediction of near-shore morphology on the time scale of a storm event and the length scale of a few surf zone widths is an active area of research. Intense wave breaking drives offshore-directed currents (undertow) carrying sediment seawards, resulting in offshore bar migration. In contrast, higher order nonlinear properties, such as wave asymmetry (velocity skewness) and velocity asymmetry, are drivers for shoreward transport. These wave processes are included in phase-resolving models such as Boussinesq-type wave models (e.g., TRITON). Short-wave averaging in the wave model yields wave-induced forces (e.g., radiation stress gradients) and a wave asymmetry term. The wave-induced forces are used in a hydrostatic model (e.g., Delft3D flow module) to drive the current and undertow, resulting in a 3D velocity profile. The wave model and hydrostatic model are coupled online with a morphodynamic model (e.g., Delft3D morphology module). The latter computes, based on the 3D flow profile and the wave asymmetry term, the sediment transport and performs the bathymetry updates. The updates are transferred directly back to the hydrodynamic models. The coupling of the wave model TRITON and the Delft3D modules is validated by comparing against extensive laboratory data sets (LIP and Boers) and a field case (Duck94), and show a good performance for the hydrodynamics and a reasonable/fair performance for the bar movements.  相似文献   

A multi-frequency Acoustic Concentration and Velocity Profiler (ACVP) for boundary layer measurements of fine-scale flow and sediment transport processes     

David Hurther  Peter D. Thorne  Mickaël Bricault  Ulrich Lemmin  Jean-Marc Barnoud 《Coastal Engineering》2011

The use of acoustics to measure sediment transport boundary layer processes has gained increasing acceptance over the past two decades. This has occurred through the development of increasingly sophisticated measuring systems and theoretical developments, which have enabled flow and suspended sediment parameters to be obtained from acoustic data with a high degree of accuracy. Until relatively recently, separate acoustic systems were used to measure flow and suspended sediment concentration. Over the past few years, however, the technology has become sufficiently advanced so that flow and sediment measurements can be integrated into a single system. This integration provides, quasi-instantaneous, non-intrusive, co-located, high temporal-spatial resolution measurements of benthic flow and sediment processes. Here the development of such an instrument, the Acoustic Concentration and Velocity Profiler (ACVP) is described. The theory underpinning its application is outlined, new approaches to velocity de-aliasing and suspended sediment inversion instabilities using multi-frequency capabilities are presented and the application of the system to sediment transport processes over a sandy ripple bed is illustrated. The observations clearly show the value of such instrumentation for studying the dynamical interaction between the bed, the flow and the sediments at and within the bottom boundary layer.  相似文献   

Improving the recreational value of Ireland's coastal resources: A contingent behavioural application     

Luke Barry  Tom M. van RensburgStephen Hynes 《Marine Policy》2011

This paper measures willingness to pay (WTP) for public access to additional beach area and trail improvements to a coastal recreational site in the west of Ireland. The Contingent Behaviour model is used to measure the increased number of trips associated with improved public access using a connecting trail between two beach areas along a stretch of Irish coastline. Results show that improving access through the use of the connecting trail increases consumer surplus by €111.15 per person per annum. It is argued that in designing new regulation such as Marine Protected Areas (MPAs) for the management of Ireland's coastline, an understanding of the values the Irish public place on coastal recreational access will be important to manage the resource in a sustainable manner.  相似文献