自由观测条件下共中心点抽道集叠加方法的误差分析     

徐永清邱苏  胡旭芝陈迪 《中国煤田地质》2007,19(2):59-62

常规共中心点抽道集叠加方法是以水平观测面,水平反射界面、均匀介质为条件,当前提条件不能完全具备时,会带来两个方面的误差,其一是CMP道集整体离散误差,其二是CMP道集内部各道之间的离散误差.通过建立相应数学模型并进行运算分析,界定了误差（离散量）的大小范围及分布规律：离散量与观测面反射界面之间的夹角、观测面高程、反射界面倾角及同道集炮检距等相关,其变化值越大,离散距离越大;相反离散距离会随观测面与反射点空间距离的增大而变小;另外介质波速越小,其垂直离散距离越大;中心点自激自收其离散量为0.对于CMP道集中诸道△t0.离散量常存在大于目的层反射波T/4的现象;炮距越大、观测界面倾角越大、介质波速越小,其△t0离散值越大,其中△t0离散值与炮检距呈非线性关系;相反反射界面埋深越大,其△t0离散越小.根据离散量对资料影响程度的分析,指出了目前共中心点抽道集叠加方法存在着局限性.  相似文献   

阿尔泰山诺尔特地区库马苏金多金属矿的发现及找矿前景     

张宗保努尔兰  林永全秦纪华 《地质通报》2007,26(3):299-304

库马苏金多金属矿床是最近在进行1∶2.5万土壤化探异常检查过程中发现的,位于新疆阿尔泰山北部诺尔特断陷盆地内。矿体产于下石炭统红山嘴组下亚组第一岩性段的凝灰质细—粉砂岩中,呈NW向带状展布,已控制矿体长逾500m,宽超过200m,矿体有北西翘起而向南东隐伏的可能,目前已控制储量金、铅、锌矿均达小型规模。矿体所在地区地球化学异常、矿化蚀变发育,矿点、矿化点密集,部分矿点已具有一定规模,只是限于地形和工作条件未进行系统的工程控制和详细检查,仅已评价过的20号矿点中就发现相当规模的矿体。通过与同一大地构造位置的哈萨克斯坦块状硫化物矿床特征的初步对比,并对区内地球化学异常、矿化蚀变带及其矿点分布情况进行综合分析,认为本区成矿条件优越,具有较好的找矿前景。  相似文献   

Tectonic and eustatic control on the distribution of black-shale source beds in the Wufeng and Longmaxi formations (Ordovician-Silurian),South China     

Su Wenbo  Li Zhiming  Ettensohn F. R.  Johnson M. E.  Huff W. D.  Wang Wei  Ma Chao  Li Lu  Zhang Lei  Zhao Huijing 《Frontiers of Earth Science》2007,1(4):470-481

It is known that high-quality, black-shale source rocks occur in the uppermost Ordovician Wufeng Formation and in the lowermost Silurian Longmaxi Formation in South China. Hence, it is important to understand their lithostratigraphy and the controls on their deposition. A review of lithostratigraphic criteria for subdividing the two adjacent formations provides new regional correlations between the formations and related stratigraphic successions and facies. Both the black shales and the related, overlying flysch deposits at the Ordovician-Silurian transition in South China appear to have migrated northwestward in time and space, reflecting probable flexural control in a foreland basin that developed in response to subduction-type orogeny southeast of the Yangtze block. The black shales also contain K-bentonites from explosive, felsic-intermediate volcanism, the distribution of which also supports orogeny to the southeast. Finally, the analysis of sequence stratigraphy, which shows that the initiation of transgressive system tracts (TST) and condensed section (CS) in the related third-order sequences coincided with the two black-shale horizons respectively, indicates that the main controlling factors for the deposition of the Ordovician-Silurian black shales in South China are (1) northwestwardly migrating, foreland-basin subsidence caused by deformational loading related to episodic accretion of the Cathaysia block to the Yangtze block during this period, and (2) the anoxic, sediment-starved water column caused by rapid rise of the sea-level during the two successive phases of third-order global sea-level rise near the Ordovician-Silurian transition in South China. In future exploration for hydrocarbon source rocks in the area, it is important to consider likely flexural and eustatic causes for subsiding, deep, anoxic seas in recognizing other source rock intervals, and our understanding of the Wufeng and Longmaxi formations may serve as models for future source rock exploration. __________ Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 818–827 [译自: 地球科学—中国地质大学学报]  相似文献   

Tectonogeochemical features and metallogenic prognosis in the Xiaolongtan copper mining district, Binchuan, Yunnan Province, China     

HE Mingqi SONG Huanbin SU Xunqing 《中国地球化学学报》2007,26(3):276-283

The Xiaolongtan copper mining district is an important area in Dali, West Yunnan, where porphyry copper deposits occur, and copper orebodies are controlled by fault or contact zone structures between porphyry massifs and country rocks. Based on detailed field investigation and deep-going analysis, the authors systematically studied the tectonogeochemical features of this mining district, proposed the principle and foundation of metallogenic prognosis, and delineated the most potential mineralization target area.  相似文献   

大溶隙岩溶地层的有效钻孔堵漏方法     

王发民石永泉  韩永昌 《探矿工程》2007,34(3):15-17

复杂地层钻探问题一直是地质勘探、工程勘察及工程施工钻进中的主要技术难题。分析了复杂地层钻探护壁堵漏的方法；结合宁夏六盘山区东北麓芒硝矿钻探工程，对于大溶隙岩溶地层钻探，提出采用水泥-水玻璃-布袋护壁堵漏方法。阐述了漏失通道的性质和位置的分析方法、护壁堵漏方案和原理、正确确定注浆压力及最大注浆量的方法。  相似文献   

Feature-Independent Aperture Evaluator for the Curvilinear SAR     

Su  Z. Peng  Y. Wang  X. 《Geoscience and Remote Sensing Letters, IEEE》2007,4(2):191-195

Curvilinear synthetic aperture radar (SAR), as a more practicable 3-D SAR imaging system, utilizes parametric target feature estimates extracted from the received data to reconstruct the target image. The reconstructed image quality is then impacted by the estimation accuracy of the features. In this letter, through discussing the correlation between the system parameters and the estimation performance of the curvilinear SAR, a conclusion can be drawn on how the overall location accuracy of a target is determined by the correlation between the azimuth and elevation coordinates of the flight path, compactly characterizing the curvilinear aperture. Consequently, a new index, determined only with the aperture parameters, is proposed as an aperture evaluator, which is referred to as the feature-independent aperture evaluator (FAE). FAE can be used for guiding the operational aperture design  相似文献   

DMC技术在土地利用现状调查中的应用与研究     

苏文强  王树文 《现代测绘》2007,30(6):22-24

本项目研究的是将Z／I Imaging的数字航摄相机（DMC）运用于土地详查项目，运用基于国际上先进Z／I Imaging DMC的拍摄技术获取的影像，结合影像融合技术，影像分类技术，土地信息提取技术，进行土地利用的动态监测及更新调查。  相似文献   

北京地区热度日和冷度日的变化特征   总被引：13，自引：3，他引：13       下载免费PDF全文

谢庄苏德斌  虞海燕李德平于丽萍  胡天洁 《应用气象学报》2007,18(2):232-236

应用1951—2004年北京逐日平均温度制作北京月、年的热度日 (HDD) 和冷度日 (CDD)。其中平均月HDD以1月 (687.9度日) 最大, 多年平均的年值为2922.6度日, 多年变化呈明显的下降趋势, 下降率为-99.5度日/10 a。平均月CDD以7月 (259.2度日) 最大。CDD多年平均的年值为826.7度日, 多年变化呈上升趋势, 上升率为39.0度日/10 a。1971—2004年HDD月城郊差值 (北京站-密云站) 冬季较大, 最大值为-73.8度日 (12月)。月CDD的城郊差值比HDD的差值小, 最大差值在8月 (34.0度日)。年HDD和CDD与年平均气温具有较高的相关性。年际、年代际HDD与年际、年代际平均气温具有反位相变化趋势, 随着气候增暖, 北京地区HDD将趋于减小, 冬季用于供暖的能源将减少; CDD将趋于增加, 夏季用于制冷降温的能源将增加。  相似文献   

Groundwater replenishment analysis by using natural isotopes in Ejina Basin, Northwestern China   总被引：4，自引：0，他引：4  

Yinghua Zhang  Y. Wu  J. Su  X. Wen  F. Liu 《Environmental Geology》2005,48(1):6-14

The Ejina Basin underlying complex aquifers is located in the lower reaches of the Heihe River with an arid climate and 40 mm mean annual precipitation. As the balance of the natural ecosystem in the Ejina Basin is fragile and easily upset, it is very important to estimate and rationally use the limited groundwater resources to maintain the balance. Water samples were collected from the Heihe River and wells for chemical and isotopic measurements across the basin. The Piper diagram gives two main types of hydrochemical features. Against the background of the regional geology, combining isotope ¹⁸O, tritium, and chemical analysis with groundwater flows indicated by a shallow groundwater level contour map, different kinds of groundwater sources and ways to replenish groundwater were discovered. North of the study area are artesian wells that are replenished by the mountainous area at the boundary between China and Mongolia. Replenishment for most of the groundwater resources of the Gurinai oasis comes from the Heihe River seepage flow of the highly conductive paleochannel, not from the Badain Jaran Desert as indicated by TDS and tritium analysis. The different groundwater ages which are younger than 35 years were approximately estimated by radioactive isotope tritium (T). By such efforts, groundwater resources can be effectively evaluated with the engineering impact of the Heihe River Project.  相似文献   

现代企业与数字信息化管理     

苏志军 《化工矿产地质》2005,27(3):173-177

数字信息化管理是企业实现现代化管理的基础,它包括企业资源分析系统和企业决策分析系统。推进数字信息管理的关键因素有管理模式的转换,量化体系的建立,"以人为本"的管理模式以及逐步将数字化管理的观念自然融入到企业文化这几个方面。建立安全、实时的企业数字化管理系统,是现代企业亟待解决的问题。  相似文献