缅北中部脉金矿带控矿因素及成矿作用浅析     

何文举 《云南地质》2001,20(3):279-288

缅北中部，印缅岛弧及弧后盆地东侧、新生代造山带的前缘推覆构造带中，分布有许多脉金矿床及矿点，构成金矿带。矿带、矿田、矿床及矿体的形成、分布及其规模，受不同级别的近南北向逆冲断裂，及其间派生的北东向张性扩容断裂组成的剪切断裂带控制。可渗透的下麦尔组下部中一粗粒砂岩，起着很好的容矿作用。下麦尔组上部泥岩、细砂岩、粉砂岩和页岩互层单元，在携金热液的迁移、氧化硅的沉淀和矿质沉积定位等方面，可能起到圈闭作用。  相似文献   

Palynostratigraphy and palynofacies indications of depositional environments and source potential for hydrocarbons: the mid Cretaceous Nahr Umr and lower Mauddud formations, Iraq   总被引：1，自引：0，他引：1  

T. K. Al-Ameri  T. K. Al-Najar  D. J. Batten 《Cretaceous Research》2001,22(6):735

Palynomorphs recovered from core and cuttings samples from five boreholes in the East Baghdad Oilfield indicate a mid Albian–early Cenomanian age-range for the Nahr Umr Formation and the lower part of the overlying Mauddud Formation. Two palynomorph zones and four types of palynofacies have been identified. The latter are interpreted to indicate delta-top swamp and marsh, silty–muddy deltaic, inner silty and carbonate-rich platform, and limestone-platform environments. The palynofacies of the two types of platform accumulations suggest that these are potential sources of biogenic methane and condensates, and may yield more liquid hydrocarbons in areas where the formations are at greater depths than within the region studied.  相似文献   

GPS工程控制网的若干特殊问题   总被引：9，自引：1，他引：9  

卓健成 《测绘工程》1996,5(1):1-7

根据ＧＰＳ定位技术的优点，讨论了建立ＧＰＳ工程控制网在踏勘、设计、观测及数据处理方面的若干特殊问题，并提出高精度工程控制网ＧＰＳ数据处理方案。  相似文献   

SPECTRUM期间目标台风移动的数值试验   总被引：2，自引：1，他引：2  

罗哲贤  马镜娴  王咏青 《气象学报》1996,54(2):166-174

在目标台风Ｙａｎｃｙ的移动过程中，选择４个时段进行预报数值试验。模式初始场系根据ＳＰＥＣＴＲＵＭ和ＴＣＭ－９０加强观测资料确定。结果表明：实际大气中目标台风移动的若干特征在模式大气中能够显示出来，如Ｙａｎｃｙ在１９９０年８月２０日００时移向的转折现象等；台风非对称结构的低频振荡是产生移向转折现象的一个重要原因。  相似文献   

冀东地区油气微渗漏地植物的遥感基础研究     

黄秀华  张磊 《遥感学报》1992,(2)

本文通过已知含油区及背景区地植物及地表土壤多种微量金属元素和吸附烃的综合分析,并利用遥感资料与物探资料作复合评价,讨论了冀东油气微渗漏地区的遥感植物地球化学标志。  相似文献   

Field compaction control studies on road bases in a new settlement area in Ghana     

E. M. Frempong 《Geotechnical and Geological Engineering》1995,13(4):227-241

Summary Among the major causes for failure of roads in the tropics is inadequate compaction during construction. There is, therefore, the need to strictly control the compaction of the pavement layers if the design life of the road is to be attained; thereby eliminating large maintenance costs.This note reports on pavement compaction control studies undertaken on the road bases of service roads in a new settlement area in Ghana. These roads were to be provided with bituminous surfacing immediately after compaction. Studies concerning particle breakdown during field compaction by two contractors executing the works under the same conditions have been made, together with an assessment of contractor efficiency.It was found that the placement moisture contents varied greatly from the optimum. One contractor was compacting the gravels on the dry side of optimum, consequently achieving relatively high densities. The other contractor was compacting on the wet side and achieving lower density levels. This was still the case even after initial test sections were found to have been undercompacted.Compaction levels achieved in the crowns were generally found to be higher than those at the shoulders of the road test sections. The breakdown of coarse particles due to compaction was quite significant. There is therefore the need for highway material engineers to ensure that in addition to meeting the grading requirements, road base materials must adequately meet the requirements on weathering and mechanical strength properties.  相似文献   

通过对调查数据的趋势和多变量分析确定宏观场     

Vala.  DR 郑鹄 《山西地震》1993,(3):43-50

通过多变(相关分析)和趋势分析等统计方法对宏观调查数据进行了解释.这种方法使我们通过评定不同宏观效应叠加的程度、估计调查数据的不确定性更客观地评定烈度.通过滤波确定烈度场的区域分量,使我们消除观测中的局部变化.给出了选取适当滤波参数的准则.本文应用这一方法对发生在意大利的一次地震的调查数据进行了处理.  相似文献   

兰州—天水地区三维重力反演及其地质解释          下载免费PDF全文

李渭娟  梁桂培  姚政生 《地震工程学报》1993,(4)

本文利用重力资料对兰州—天水地区的深部构造进行了研究。在计算中,采用Parker-Oldenbarg三维位场反演方法,反演前对重力资料进行了地形改正和中新生代沉积层校正。根据反演结果,综合分析了有关资料,认为该区为青藏块体过渡带,并且提出了陇中盆地为断块型构造盆地的新认识。  相似文献   

Meso-scale testing and development of test procedures to maintain mass balance     

Bonner J  Page C  Fuller C 《Marine pollution bulletin》2003,47(9-12):406-414

The Conrad Blucher Institute for Surveying and Science (Texas A&M University––Corpus Christi) has conducted numerous petroleum experiments at the Shoreline Environmental Research Facility (Corpus Christi, Texas, USA). The meso-scale facility has multiple wave tanks, permitting some control in experimental design of the investigations, but allowing for real-world conditions. This paper outlines the evolution of a materials balance approach in conducting petroleum experiments at the facility. The first attempt at a materials balance was during a 1998 study on the fate/effects of dispersant use on crude oil. Both water column and beach sediment samples were collected. For the materials balance, the defined environmental compartments for oil accumulation were sediments, water column, and the water surface, while the discharge from the tanks was presumed to be the primary sink. The “lessons learned” included a need to quantify oil adhesion to the tank surfaces. This was resolved by adhering strips of the polymer tank lining to the tank sides that could be later removed and extracted for oil. Also, a protocol was needed to quantify any floating oil on the water surface. A water surface (oil slick) quantification protocol was developed, involving the use of solid-phase extraction disks. This protocol was first tested during a shoreline cleaner experiment, and later refined in subsequent dispersant effectiveness studies. The effectiveness tests were designed to simulate shallow embayments which created the need for additional adjustments in the tanks. Since dispersant efficacy is largely affected by hydrodynamics, it was necessary to scale the hydrodynamic conditions of the tanks to those expected in our prototype system (Corpus Christi Bay, Texas). The use of a scaled model permits the experiment to be reproduced and/or evaluated under different conditions. To minimize wave reflection in the tank, a parabolic wave dissipater was built. In terms of materials balance, this design reduced available surface area as a sink for oil adsorption.  相似文献   

Development of airborne oil thickness measurements     

Brown CE  Fingas MF 《Marine pollution bulletin》2003,47(9-12):485-492

A laboratory sensor has now been developed to measure the absolute thickness of oil on water slicks. This prototype oil slick thickness measurement system is known as the laser-ultrasonic remote sensing of oil thickness (LURSOT) sensor. This laser opto-acoustic sensor is the initial step in the ultimate goal of providing an airborne sensor with the ability to remotely measure oil-on-water slick thickness. The LURSOT sensor employs three lasers to produce and measure the time-of-flight of ultrasonic waves in oil and hence provide a direct measurement of oil slick thickness. The successful application of this technology to the measurement of oil slick thickness will benefit the scientific community as a whole by providing information about the dynamics of oil slick spreading and the spill responder by providing a measurement of the effectiveness of spill countermeasures such as dispersant application and in situ burning.

This paper will provide a review of early developments and discuss the current state-of-the-art in the field of oil slick thickness measurement.  相似文献