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961.
新疆金地球化学块体内资源潜力预测及找矿方向探讨 总被引:1,自引:1,他引:1
新疆地域广大,成矿地质和地球化学条件极好,有着巨大的找矿潜力.据统计,在新疆已知岩金矿床中。有70%是通过区域化探直接或间接发现的.本以谢学锦院士1995年提出的地球化学块体理论为指导,利用区域化探信息系统和新疆已有区域化探数据,从地球块体角度对新疆金矿进行了资源潜力预测和找矿方向探讨.全疆共圈定金地球化学块体27个,并对各金地球化学块体基本特征及其与已知金矿的对应关系进行了剖析.研究表明。金地球化学块体规模及浓集度越大、块体结构越复杂,其金资源量和资源潜力就越大;反之越小.在综合研究基础上。按金资源量由大到小的顺序,将新疆各地区金资源潜力大小和金矿主攻地区排序为西天山、东天山、西准噶尔、阿尔泰、西昆仑、东准噶尔和阿尔金地区. 相似文献
962.
赣东北横路——赋春成矿带的金矿成矿条件及找矿方向 总被引:4,自引:0,他引:4
本文详细阐述了赣东北横路—赋春成矿带的金矿成矿条件及成矿规律,重点对可望突破的金矿床(点)作了较为详细具体的论述,提出了今后的找矿方向。 相似文献
963.
西昆仑造山带北西向拉伸线理特征及其地质意义 总被引:1,自引:0,他引:1
初步研究了西昆仑造山带广泛发育的一组NW—NWW向拉伸线理的矿物组成、产状、分布层位等特征,探讨了其成因。认为该组线理为区内第三主变形期的“陆内榨挤”阶段导致西昆仑造山带逆冲推覆断层系被激发转变为大规模NW—NWW向右旋平移走滑的产物。 相似文献
964.
阿舍勒铜锌矿床的开合构造特征及找矿方向 总被引:6,自引:1,他引:6
在总结该矿床形成的开合构造环境,火山-沉积建造序列,变形序列,成矿序列,裂谷带发展多旋回,开合构演变特征,矿床成矿规律,找矿方向的基础上,提出了6点基本结论。 相似文献
965.
Several issues considered to be fundamental in quantitative estimation of mineral resources and selection of mineral targets are addressed. Integration of multiple data sets, either by experts or by statistical methods, has become a common practice in estimation of mineral potential. Several major problems in data integration must be solved to significantly improve mineral resource estimation. Issues related to randomness of mineral endowment, basic statistical tools, exceptionalness of ore, and economic truncation and translation are discussed in the first part of the article. A number of important technical problems in data integration are also identified; they include data compilation, information enhancement, information synthesis, and target selection. 相似文献
966.
本文利用迭代目标转换因子分析光度法,用高灵敏显色剂水扬基萤光酮(SAF).在CTMAB存在的强酸性介质中,对标准合成试样及合金标样中Ti、Zr、Nb的同时测定进行了研究.结果表明,相对误差一般都在10%以内,相对标准偏差<5%,获得满意结果. 相似文献
967.
饮用天然矿泉水是近来来国内外市场上走俏的一种新型天然保健饮料。陕西省已发现78处矿泉水。本文据全省矿泉水产出的地质一水文地质条件,分析了矿泉水的形成原因,指明了进一步寻找矿泉水的靶区,并为全省矿泉水资源的开发与保护提供了经验。 相似文献
968.
Three nonparametric techniques for the optimum discretization of quantitative geological features are proposed and demonstrated. The three methods are: isolated weight, entropy information, and rank correlation. Optimum discretization plays important roles in solutions to the following geoscience problems: (1) signal/noise separation and delineation of meaningful anomalies and other geofields related to mineral targets; (2) selection of those geological variables that explain variations in mineral resources; (3) determination of the best subintervals of values for a variable with respect to mineralization; (4) enhancement of certain complex and concealed information of a geofeature about its correlation with magnitude of mineralization; and (5) unification of diverse geodata so that these data can be integrated and analyzed. 相似文献
969.
Multiple deformation in all the Precambrian metamorphic-migmatitic rocks has been reported from Rajasthan during the last
three decades. But, whereas the Aravalli Group and the Banded Gneissic Complex show similarity in the style and sequence of
structures in all their details, the rocks of the Delhi Group trace a partly independent trend. Isoclinal folds of the first
generation (AF1) in the rocks of the Aravalli Group had gentle westerly plunge prior to later deformations. These folds show reclined, inclined,
and upright attitude as a result of coaxial upright folding (AFla). Superposition of upright folds (AF2) of varying tightness, with axial plane striking N to NNE, has resulted in interference patterns of diverse types in the
scale of maps, and deformation of earlier planar and linear structures in the scale of hand specimens. The structures of the
third generation (AF3) are either open recumbent folds or reclined conjugate folds with axial planes dipping gently towards NE or SW. Structures
of the last phase are upright conjugate folds (AF4) with axial planes striking NNE-SSW and E-W.
The Banded Gneissic Complex (BGC) underlies the Aravalli Group with a conglomerate horizon at the contact, especially in southern
Rajasthan. But, for a major part of central and southern Rajasthan, migmatites representing BGC show a structural style and
sequence identical with those in the Aravalli Group. Migmatization, broadly synkinematic with the AF1 folding, suggests extensive remobilization of the basement. Very rare relict fabric athwart to and overprinted by structures
of AF, generation provide tangible evidence for a basement.
Although the structures of later phases in the rocks of the Delhi Group (DF3 and DF4) match with the late-phase structures in the Aravalli Group (AF3 and AF4), there is a contrast in the structural history of the early stages in the rocks of the two groups. The folds of the first
generation in the Delhi Group (DF1) were recumbent to reclined with gentle plunge towards N to NNE or S to SSW. These were followed by coaxial upright folds
of varying tightness (DF2). Absence of westerly trending AF1 folds in the Delhi Group, and extreme variation in plunge of the AF2 folds in contrast with the fairly constant plunge of the DF2 folds, provide evidence for an angular unconformity between the Aravalli and the Delhi Groups.
Depending on the importance of flattening attendant with and following buckling during AF2 deformation, the lineations of AF1 generation show different patterns. Where the AF1 lineations are distributed in circular cones around AF2 axes because of flexural-slip folding in layered rocks with high viscosity contrast, loci of early lineations indicate that
the initial orientation of the AF1 axes were subhorizontal, trending towards N280°.
The orientation of the axial planes of the earlier folds has controlled the development of the later folds. In sectors where
the AF, axial planes had N-S strike and gentle dips, or E-W strike with gentle to steep dips, nearly E-W horizontal compression
during AF2 deformation resulted in well-developed AF2 folds. By contrast, where the AF, axial planes were striking nearly N-S with steep dips, E-W horizontal compression resulted
in tightening (flattening) of the already isoclinal AF1 folds, and probably boudinage structures in some instances, without the development of any AF2 folds. A similar situation obtains when DF4 deformation is superposed on earlier structures. Where the dominant S-planes were subhorizontal, N-S compression during DF4 deformation resulted in either chevron folds with E-W striking axial plane or conjugate folds with axial plane striking NE
and NW. In zones with S-planes striking E-W and dipping steeply, the N-S compression resulted in flattening of the earlier
folds without development of DF4 folds. 相似文献
970.
作者在总结黄山东铜镍矿床地质、地球化学特征的基础上,提出了该区地质、地球化学找矿指标,并对土墩—黄山成矿带1528km~2范围内的39处异常进行了初步评价,提出了找矿靶区. 相似文献