开发尺度的曲流河储层内部结构地震沉积学解释方法

曲流河地层内部结构复杂,岩性界面具有穿时性,传统的地震相分析法不能满足油藏开发地质研究中对储层内部结构精细解释的需要,急需探索有效的地震解释方法。采用基于探地雷达的露头探测、点坝复合体三维正演模拟和实际地震资料相结合的方法,分析了地震资料频率和地层厚度对曲流河内部结构地震反射特征的影响,研究了利用地层切片解释曲流河沉积结构的原理和方法,建立了开发尺度的曲流河内部结构地震沉积学解释技术。研究发现:(1)高频地震资料中地震反射能够反映曲流河侧积复合体边界,而低频地震资料中反射同相轴与岩性界面一致;(2)不同厚度的点坝侧积单元地震反射特征存在差异,造成反射剖面的多解性。同时指出曲流河内部结构地震沉积学解释的技术关键:(1)发挥地震资料平面与剖面信息的相互约束和补充;(2)将地质体作为三维空间发育的成因体,利用其平面与剖面特征的成因联系指导解释;(3)级次化解释方法,在不同级次上采用针对性的解释方法。将该方法应用于墨西哥湾新近系地震沉积学解释,实现了曲流河点坝复合体内部结构的三维刻画。     

伽玛能谱参数与金矿找矿

γ能谱测量方法是一种简便、有效、快速的间接找金的方法,不同类型的金矿其伽玛能谱特征并不相同。与深成脉岩活动有关的脉状金矿,具有明显的伽玛能谱Ｋ／Ｕ参数异常;与中浅成中酸性侵入发杂岩体有关的金矿,具有Ｋ／Ｕ,Ｋ／Ｔｈ参数正异常;而与浅成－超玫成偏碱性杂岩体有关的隐爆角砾岩型金矿,则具有一致的Ｕ,Ｔｈ,Ｋ及Ｆ参数正异常。本介绍了在山东东部乳山地区及临沂西部地区,利用没的伽玛能谱参数进行不同类型的金矿     

赣北修水观音阁砾岩特征及其构造意义

有关赣北地区双桥山群内角度不整合和地壳运动存在与否问题,一直争论不休。论文以较丰富的详细野外调查资料为基础,并结合前人研究成果和室内各类样品测试结果,围绕这个赣北地区重要的基础地质问题进行了讨论。作者认为“修水运动”不能成立,并提出了砾岩的沉积模式。     

海上钻孔灌注桩成孔施工技术

介绍了东海大桥钻孔灌注桩基础的施工技术 ,对一些关键技术做了详细说明 ,还讨论了海上钻孔灌注桩施工成孔设备的选择及所用的淡水泥浆的配制     

郴桂地区中大比例尺成矿预测的方法与效果

郴桂地区是南岭多金属成矿带的重要地段，地质矿产工作研究程度较高，我院在此开展了大中比例尺成矿预测研究。本文扼要介绍了本区成矿预测的基本做法和预测方法，以及其主要成果和验证效果。     

Geochemical characteristics and genetic types of crude oils from Qinjiatun and Qikeshu oilfields in the Lishu Fault Depression,Songliao Basin,northeastern China

The Qinjiatun and Qikeshu oilfields are new Mesozoic petroleum exploration targets in Lishu Fault Depression of Songliao Basin, northeastern China. Currently, researches on geochemistry of crude oils from Qinjiatun and Qikeshu oilfields have not been performed and the genesis of oils is still uncertain. Based on bulk analyses, the crude oils in the Qinjiatun and Qikeshu oilfields of Lishu Fault Depression from the Lower Cretaceous can be classified as three types. TypeⅠoils, from Quantou and Denglouku formations of Qikeshu oilfield, are characterized by high C24tetracyclic terpane/C26tricyclic terpanes ratios, low gammacerance/C30hopane ratios, tricyclic terpanes/hopanes ratios, C29Ts/C29norhopane ratios and 17α(H)-diahopane/17α(H)-hopane ratios, indicating a brackish lacustrine facies. TypeⅡoils, from Shahezi Formation of Qikeshu oilfield show low C24tetracyclic terpane/C26tricyclic terpanes, high gammacerance/C30hopane ratios, tricyclic terpanes/hopanes ratios, C29Ts/C29 norhopane and C30diahopane/C30hopane ratios, thus suggesting that they originated from source rocks deposited in a weak reducing brackish lacustrine environment, or clay-rich sediments. Type oilsⅢ, from some wells of Qikeshu oilfield have geochemical characteristics intermediate between those two types and may be mixture of typeⅠand Ⅱoils.     

A method for mineral prospectivity mapping integrating C4.5 decision tree,weights-of-evidence and m-branch smoothing techniques: a case study in the eastern Kunlun Mountains,China

In this study, a novel method that integrates C4.5 decision tree, weights-of-evidence and m-branch smoothing techniques was proposed for mineral prospectivity mapping. First, a weights-of-evidence model was used to rank the importance of each evidential map and determine the optimal buffer distance. Second, a classification technique that uses a C4.5 decision tree in data mining was used to construct a decision tree classifier for the grid dataset. Finally, an m-branch smoothing technique was used as a predictor, which transformed the decision tree into a probability evaluation tree. The method makes no conditional independence assumption and can be applied for class imbalanced datasets like those collected during mineral exploration for prospectivity mapping of an area. The traits of comprehensibility, accuracy and efficiency were derived from the C4.5 decision tree. In addition, a case study for iron prospectivity mapping was performed in the eastern Kunlun Mountains, China. Sixty-two Skarn iron deposits and eight evidential maps related to iron mineralization were studied. On the final map, areas of low, moderate and high potential for iron deposit occurrence covered areas of 71,491, 14,298, and 9,532 km², respectively. For the goodness-of-fit test, 91.94 % of the total 62 iron deposits were within a high-potential area, 8.06 % were within a moderate-potential area and 0 % were within a low-potential area. For ten-fold cross-validation, 82.26 % were within a high-potential area, 14.52 % were within a moderate-potential area and 3.22 % were within a low-potential area. To evaluate the predictive accuracy, Receiver Operating Characteristic (ROC) curves and Area Under ROC Curve (AUC) were employed. The accuracy of the goodness-of-fit test reached 97.07 %, and the accuracy of the ten-fold cross-validation was 95.10 %. The majority of the iron deposits were within high-potential and moderate-potential areas, which covered a small proportion of the study area.     

黔东南地区新元古代下江群的地层年代及其地质意义

黔东南地区下江群是分布在江南造山带西段的一套前寒武纪浅变质陆源碎屑岩夹火山碎屑岩组合, 其地层时代归属与划分特别是区域地层对比一直未能得到很好解决.在对该区前寒武纪地层广泛而详细的剖面测制和地质调查基础上, 运用LA-ICP-MS技术, 对地层中沉凝灰岩、含凝灰质碎屑岩和碎屑岩进行锆石U-Pb年代学测试, 获得一批高精度的年龄.四堡群河村组顶部的碎屑岩和下江群乌叶组第1段顶部的含凝灰质碎屑岩、清水江组底部与中部的沉凝灰岩、平略组中上部的含凝灰质碎屑岩、隆里组中下部的碎屑岩等样品中锆石U-Pb最小年龄组的加权平均年龄分别为819.8±6.4Ma和779.5±4.7Ma、764.0±6.3Ma与(756.8±7.6Ma、756.0±13.0Ma)、733.9±8.8Ma及725.0±10.0Ma.这些数据将四堡群和下江群的时代限制为新元古代.结合研究区隆里组与长安组整合接触关系和全球低纬度南华系冰期起始年龄(717.4Ma)的地质事实, 将下江群沉积时限约束在815~717Ma之间.根据区域岩浆事件进一步约束了下江群各组段的地层时限, 并开展江南造山带下江群及其相当层位的地层划分与对比, 认为新元古代岩浆作用制约着黔东南下江群盆地的演化.      

贵州六盘水地区水城矿区晚二叠世煤的煤质特征及其控制因素

本文中研究概括了六盘水地区水城矿区晚二叠世煤的煤岩学、煤化学和煤地球化学的研究结果,探讨了煤质的控制因素。研究结果表明水城矿区煤具有适合于炼焦用煤的煤岩煤质特征（中挥发分烟煤和高挥发分烟煤Ａ,适中的显微组分比例,４９．９％～８１．８％镜质组,１１．９％～３１．９％惰性组,０．４％～１６．９％壳质组,中－低的硫含量,０．３４％～１．５％）。水城煤的煤级主要受深成变质作用的影响。水城煤的岩石学特征主要受晚二叠世水城三角洲的控制。将水城矿区煤的微量元素含量与世界平均的微量元素进行比较,水城煤具有Ｓｅ、Ｚｒ、Ｃｒ、Ｃｏ、Ｕ和Ｔｈ稍高富集,Ｃｓ、Ａｓ和Ｂａ低富集的特点。煤中Ｂｒ和Ｃｌ具有亲有机性     

准噶尔盆地基底火山岩中的辉石及其对盆地基底性质的示踪

根据钻井和航磁资料，准噶尔盆地基底可划分为西、北、南三区。3个地区火山岩中辉石的化学成分、种属名称各不相同。辉石化学成分反映出来的寄主岩的碱度、碱度演化趋势以及寄主岩形成的构造环境、构造环境演化史均各有差异，佐证了准噶尔盆地基底是由哈萨克斯坦板块东南缘、西伯利亚板块西南缘和塔里木板块北缘增生大陆拼合而成。其中西、北两区拼合较早，早石炭世末的早海西运动时抬升成陆；南区成陆较晚，晚古炭世末的晚海西运动使南区与西、北两区联合大陆对接，形成完整的准噶尔盆地海西褶皱基底。