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81.
库米什盆地的硝酸盐型钾盐矿床   总被引:1,自引:0,他引:1  
库米什盆地的硝酸盐型钾盐矿床,是利用~(40)K具有放射性特点,通过航空、地面伽玛能谱测量发现的。本文介绍了具有代表性C矿床的一般地质特征,总结了乌尊布拉克硝酸盐型钾盐矿床地质特征。矿床按其赋存状态可分为固体矿和卤水矿两类。水硝碱镁矾为最主要的工业矿物,共生矿物有钾硝石、钠硝石、杂卤石、芒硝、钠镁矾、石膏、石盐、极少量的泻利盐等。  相似文献   
82.
This paper discusses geological-geophysical-geochemical models of such typical deposits as the Tieshan-type Fe-Cu deposit, the Tonglushan-type Cu-Fe deposit, the Yehuaxiang-type Cu deposit, the Jiguanzui-type Cu-Au deposit, and the Tongshankou-type Cu (Mo) deposit. The models were established based on practical data of the polymetallic deposits dominated by copper ore in southeastern Hubei. These models, which are graphically illustrated in the paper, systematically summarize the metallogenic geological conditions and the geophysical-geochemical characteristics of copper deposits in this area. The models are of practical significance for studying copper deposits, predicting mineral resources, choosing exploration methods, and searching for ore deposits based on existing ones in the study area.  相似文献   
83.
Monthly consumption forecasts for U.S. oil, natural gas, and coal are made using state space and multiple regression applied to the same data. These forecasts are compared with actual consumption for a test period. The forecasts made using state space are preferred to those made using multiple regression models for both expost and exante cases. The state space forecasts track data cycles better than do the regression forecasts. Average absolute forecast errors are less for the state space models than they are for the multiple regression models.  相似文献   
84.
本文采用同时具有识別、分解、解释异常三重作用的三元解释法■,在黄沙坪异常负值区有效地提取了由未知的深源磁性体引起的剩余异常。该异常与已知的中、浅源磁性体分处于极为类同的成矿地质背景中。后者与隐伏岩体、铅锌多金属盲矿体之间有着密切的成生联系。这为前者间接找矿提供了有力的依据。定量解释结果中,两者间的磁矩等效关系,论证了已知矿床西侧深部空间里,仍存在找到又一个大型矿床的前景。  相似文献   
85.
本矿物为新发现的钇易解石族的端员矿物-钛钇易解石,产于江西省龙南县足洞燕山期中粒白云母花岗岩及其风化壳中。矿物属斜方晶系,常呈板状或短柱状,为天然晶质体,浅黄色,粒度为0.075mm,硬度4.7,比重4.73,二轴正晶,Ng=2.248,Nm=2.212,Np=2.194,Ng-Np=0.054,2V=70°。空间群为D^162h-Pmnb,a0=0.750nm,b0=1.092nm,C0=0.5  相似文献   
86.
华北地区重力场与沉积层构造   总被引:12,自引:2,他引:12  
位于中朝准地台的华北地区是由几个不同的断块组成的,重力异常场的分布具有很强的浅部效应、块状分布和深浅叠加场的特点。重力的高程效应很复杂,不同波长的起伏变化有不同的影响系数。本文对布格改正的有关问题进行了讨论,指出华北如区表浅层的密度值偏低(2520kg/m3),该区合理的布格改正公式为△g2=-0.0879H。将重力场的垂直导数和向上延拓结合起来,有利于揭示地壳上部构造特征。本文搜集整理了由第四系到寒武系的沉积层资料,给出了沉积层总厚度和视密度的分布。对深部重力异常的分析表明,华北沉积层的形成有深源性质,在均衡调节中起着一定的内载荷作用。  相似文献   
87.
This paper discusses the Cretaceous-Tertiary magnetic polarity sequence of the the Hengyang Basin on the basis of magnetostratigraphic study. The age of each stratigraphic unit has been determined with the magnetic polarity time scale combined with 39Ar/40Ar dating, thus providing evidence for determining the geological ages of different formations. The authors assign the age of the Dongjing Formation of the Hengyang Basin to Early Cretaceous, the Shenhuangshan Formation to Early-Late Cretaceous, the Daijiaping Formation to Late Cretaceous, and the Dongtang and Xialiushi formations to Palaeocene.  相似文献   
88.
Physicochemical parameters of mineralization such as temperature, pressure, salinity, density, composition and boiling of ore fluids as well as pH, Eh, fo2 and reducing parameter in theprocess of mineralization of major ore deposits in the study district have been obtained by the authors through systematic observation and determination of characteristics and phase changes of fluid inclusions at different temperatures and analysis of gaseous and liquid phase compositions of the inclusions, thus providing a scientific basis for the division of mineralization-alteration stages, types of mineral deposits and minerogenetic series and the deepening of the knowledge about the ore-forming processes and mechanisms of mineral deposits. It is indicated that the deposits of the same type have similar fluid inclusion geochemical features and physicochemical parameters though they belong to different minerogenetic series, while the compositions of inclusions are not conditioned by deposit types but closely related to  相似文献   
89.
l. IntroductionGranite distributes widely in western KunlunMts. Many researches have been conducted byscientists (Wang Yuzhen et.al., l987; Zhang Yuquanet.al., l989, Fang Xilian et.al., I990, Jiang Chunfaet.al., 1992; Pan Yusheng, l992, Xu Ronghua et.al.,l 994; Jing Daogui et.al., l996, Zhang Yuquan et.al.,l998). But all of the researches have been donealong Sino-Pakistan road and Xinjiang-Tibet roadt"ith fOcus on isotopic dating of the intrusion andconducted a few on origin and tect…  相似文献   
90.
The genetic analysis of the deep-buried reservoirs of the Lower Paleozoic carbonate rocks in the Tarim basin is a difficult task involving many factors. Firstly, the object of study is carbonate rocks, which have undergone a long term of modification. Secondly, the rocks are deeply buried with depths of 3800-7000 m in the Tarim basin. The primary reservoir properties formed in the deposition have been strongly modified during the deep burial process. Concurrently, the different burial depths in different areas result in diversities of burial temperature, pressure, underground water, hydrochemistry and various physicochemical changes, which further lead to differences in the diagenetic type, diagenetic property, diagenetic degree and their impacts on the reservoir properties. The Lower Paleozoic Cambrian and Ordovician carbonate reservoirs in the Tarim basin can be grouped into four types, i.e., paleo-weathered-crust reservoirs, reef reservoirs, buried karst reservoirs and dolomite reservoirs. This paper  相似文献   
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