秦岭成矿带Pb、Zn化探异常与铅锌矿 常无对应关系的原因

秦岭成矿带中Pb、Zn化探异常区常无铅锌矿,而铅锌矿区又常无Pb、Zn异常,这种Pb、Zn异常与铅锌矿的不对应关系,通常导致大量的Pb、Zn异常无找矿指示意义,甚至给找矿评价、勘查部署选区工作带来了某些误导。本次的大量实验研究表明,秦岭地区水系沉积物中Pb、Zn元素主要在较粗粒级(-10~+60目)组分和细粒(小于140目)组分两端粒级中富集,而在中等粒度(80~120目)中贫化。以往所采用的统一粒度(-60目)样品分析所圈定的Pb、Zn异常,主要是细粒级吸附态的Pb、Zn在远离铅锌矿源区富集的反映,强化了远离矿源“次生富集”的信息。据此建议,在秦岭地区开展的面积性化探工作中,首先通过典型矿区粒级试验,建立区内不同背景区成矿元素的合理粒级范围,使所选用的粒度组合(粗、中、细粒)对在不同粒级中富集的元素更具代表性,改变秦岭Pb、Zn等化探异常指导找矿工作的被动局面,确保化探工作能更好地指导地质找矿和勘查部署选区工作。     

河南省灵宝市朱阳盆地地热形成条件分析

地热资源是一种优质、清洁的可再生能源,开发利用地热资源有利于补充和缓解当前能源紧缺,同时也是人类实现可持续发展的需要。以河南省灵宝市朱阳盆地地热资源为研究对象,工作区为河南省灵宝市朱阳镇断陷盆地,面积约135 km2,重点调查区为朱阳镇至鱼哭寺一带,面积约30 km2。在重点调查区共完成水文地球化学测量勘测线六条,通过本次汞、氡气的测定,确定出小河断裂在朱阳盆地的位置与走向。确定出芋园村—五亩断裂在朱阳盆地的位置与走向。建议用可控源音频大地电磁(CSAMT)方法或地震勘探来查清工作区东部的深部地层岩性、结构、形态、地下热水富集情况。     

DLG数字产品的质量评定研究

随着信息化的发展,地理信息数字产品的质量特点发生了质的变化,如何科学评定DLG数字线划图的质量是本文探讨的重要问题.本文提出应用模糊数学理论,用模糊综合评价法评定DLG数字产品的质量,并且建立了该方法的数学模型,确定了质量评价体系的指标因素和权重等.结合具体实例详细阐述了DLG数字线划图的模糊综合评价方法,进一步验证此方法行之有效.     

川西坳陷中段三叠系雷口坡组—马鞍塘组油气地质条件及有利勘探目标分析

川西地区三叠系发育马鞍塘组滩相裂缝-孔隙型储层、雷口坡组顶部不整合面岩溶缝洞型储层以及雷口坡组台地边缘滩和台内滩相孔隙型储层等多套多种类型的碳酸盐岩储层,油气地质条件良好。认为川西坳陷中段孝新—合丰构造带主要以雷口坡组台内滩、不整合面岩溶储层及马鞍塘组滩相储层为主要勘探目标层系,其中孝泉、新场构造是近期该构造带最有利的勘探目标。坳陷西缘构造带主要以雷口坡组台缘滩及马鞍塘组浅滩相储层为主要勘探目标层系,圈闭面积较大的安县、鸭子河、大邑构造是该构造带风险勘探的有利目标。坳陷东坡构造带主要以雷口坡组台内滩相及不整合面岩溶储层为目标。     

九江—瑞昌地区中新生代滑脱构造研究

九江—瑞昌地区中新生代发育多层次、多期次、多形式的滑脱构造.受基底拆离断层、中新元古界/震旦系不整合面和志留系三套区域滑脱层(面)的控制,不同层次的构造变形差异明显,可概括为前震旦系基底滑脱系统、寒武—奥陶系滑脱系统、志留系滑脱系统和泥盆—三叠系滑脱系统.在不同时期不同大地构造背景下,发育了不同类型的滑脱构造:晚侏罗世至早白垩世初挤压型滑脱构造、早白垩世初(140 Ma)伸展型拆离滑脱构造及早白垩世晚期(113 Ma)重力滑脱构造.     

甘肃西和大桥金矿区复杂地层钻探施工实践

针对甘肃西和大桥金矿区地层破碎、裂隙发育,漏失、坍塌、卡钻、埋钻等钻进难点,采用金刚石单动双管钻进工艺和聚丙烯酰胺小分散低固相冲洗液护孔技术,并采用多种堵漏措施,取得了较好的技术效果。总结了该矿区复杂地层钻探施工的经验。     

河北省铁矿分布与重磁场特征的关系

在河北省铁矿资源潜力评价及成矿预测中,对重力场、磁场特征进行了总结和归纳,认为规模较大的航磁正异常主要是出露或隐伏侵入岩基的反映;大面积分布的低缓正磁异常区则主要反映了太古宙变质岩系或基底隆起的边缘,沉积变质型铁矿主要密集分布在此区域;负磁场区主要出现在中上元古界、古生界碳酸盐岩和中生界酸性火山—沉积岩系;强度高、梯度大、或有明显负值伴生的局部磁异常则可能是磁性铁矿的反映。从重力场特征看,磁性铁矿主要分布在布格重力异常的梯级带或异常扭曲处,以及正、负异常的交界处,这些地方多与地质构造强烈变形密切相关。只有对重磁场进行深入地质剖析,结合典型矿床上建立的识别标志进行对比分析,才能得出一个符合客观实际的地质解释。     

苏里格气田西区低阻气层成因分析

苏里格气田西区上古生界二叠系的主要含气目的层为盒8段及山1段,而此区域高阻气层与低阻气层共存,运用电阻率难以区分气层与水层,这给测井评价带来很大难度。因此正确认识低阻气层的成因,对准确识别储层中流体类型十分重要。本次研究从沉积背景、储层岩性、储层物性和钻井工程的角度出发,对低阻气层的成因和特点进行了分析,认为粘土矿物分布,泥浆滤液侵入是造成气层低阻的主要因素,而高不动水饱和度是引起该区气层低阻的最主要原因。另外高地层水矿化度,也是造成该区低阻的成因。通过此次研究,其成果可为该区低阻气层的正确识别和评价提供重要依据。     

黔南晚石炭世旋回珊瑚礁群落演化研究

发育于黔南地区的扁坪—岩板寨晚石炭世旋回珊瑚礁由3个旋回组成,每个旋回都具有较高的生物含量和生物多样性。根据生物的丰度和功能可识别出叶状藻-"不明管状物"群落、Ivanovia cf.manchurica群落、Tubiphytes群落和Fomitchevella群落。旋回珊瑚礁的演化过程可划分为6个阶段。分析表明,礁体形成过程中曾一度出现了高能的环境,第二、三旋回经历了迅速的环境变化。     

基于深度卷积嵌入式聚类（DCEC）的海洋环境特征提取对渔情预报模型的改进研究

In order to improve the forecasting ability of the fishery forecast model for the longline bigeye tuna (Thunnus obesus), we proposed a marine environment feature extraction method based on deep convolutional embedded clustering (DCEC), combined with generalized additive model (GAM) for forecasting the longline bigeye tuna fishing grounds in the Southwest Indian Ocean. We used the MODIS-Aqua and MODIS-Terra sea surface temperature (SST) three-level inversion image data (in days) from January to December in 2018 at 0.041 6°×0.041 6° to construct a DCEC model, determined the optimal number of clusters based on the Davies-Bouldi index (DBI), and extracted the category feature value (F_M) of each month’s sea surface temperature (SST); we used monthly 1°×1° bigeye tuna longline fishery data from January to December in 2018 generated from the Indian Ocean Tuna Commission (IOTC), and calculated the catch per unit effort (CPUE); we matched the monthly category feature value F_M and the monthly average value of Chl a concentration with the CPUE data to construct an improved GAM; we matched the monthly average SST, the monthly average Chl a concentration and CPUE data to build a basic GAM; we used the joint hypothesis test (F test) to verify the influence of model explanatory variables; we used akaike information criterion (AIC), mean square error (MSE), and draw the frequency distribution diagrams and box diagrams of measured and predicted values, etc., to analysis the improvement effect of the improved GAM compared to the basic GAM. The results showed that: (1) the category feature value (F_M) extracted based on the DCEC model could better reflect the temporal and spatial dynamic characteristics of SST in the Southwest Indian Ocean, and was related with the climatic conditions, monsoon conditions, and hydrological characteristics in the Southwest Indian Ocean; (2) the factor interpretation of F_M was higher than that of the monthly average SST in GAM, which means F_M had more significant impact on the CPUE of bigeye tuna. The high catch rate was concentrated in the areas where the F_M category was 2, 10, 24 with intersections between the warm and cold currents; (3) the AIC of the improved GAM was reduced by 9.17% than that of the basic GAM and MSE of the improved GAM was reduced by 26.7% than that of the basic GAM; the frequency distribution of the CPUE logarithmic value predicted by the improved GAM was closer to the normal distribution, and the high frequency distribution interval was closer to that of the measured value; the scatter plot showed that the CPUE predicted by the improved GAM had a significant correlation with the measured CPUE, with r equaled to 0.60. This study proves the effectiveness of the DCEC model in extracting marine environmental features, and can provide a reference for the further study on the bigeye tuna fishery forecast.