中国锡矿床时空分布特征与潜力评价

锡矿是中国传统优势矿种,但是近年来遇到了找矿潜力区不足和找矿方向不明等问题,急需进一步分析和总结其地质特征、成矿规律和资源潜力,为今后地质找矿工作提供借鉴。文中采用矿床模型综合地质信息预测方法,在各省区锡矿资源潜力预测成果的基础上,以MapGIS为平台,进行数据库汇总与综合分析研究。首先,基于全国893处锡矿产地数据的统计分析,初步总结了中国锡矿时空分布特征,岩浆岩、构造和地层等控矿因素。其次,根据锡矿床及预测区的空间分布和大地构造单元,划分了44个锡矿成矿区带。再次,将锡矿的预测类型划分为石英脉型、锡石硫化物型、夕卡岩型、云英型、伟晶岩型、火山岩型和砂矿型,并建立了主要锡矿类型的预测模型。最后,在全国范围累计圈定1 179个最小预测区,累计预测资源量1 861.13×104 t。根据锡矿区域成矿特征,将最小预测区归并为405个二级预测区,并进一步合并为109个锡矿三级预测区,其中找矿潜力大的湖南香花岭-千里山和塔山-大义山、云南个旧和薄竹山-都龙、内蒙古黄冈梁等5个三级预测区可优先部署锡矿勘查工作。预测结果还表明锡矿在500 m以浅的找矿空间里仍有很大资源潜力,因此,找矿工作应注重深浅结合,在重视老矿山深部外围找矿的同时,还应重视覆盖区和非传统锡矿类型等新领域的找矿勘查。     

黑龙江省金属矿产资源经济战略分析

阐述了黑龙江省所有探明金属矿种的资源状况和勘查开发利用现状,以及矿山当前的经营状况、经济效益等,并从经济战略上对黑龙江省金属矿产资源的预测、找矿、勘查、开发进行了长远规划,为省政府决策机构对省内外金属矿产资源经济战略布局提供依据。     

华北地区镍矿床特征及资源潜力

华北地区镍矿床(点)主要分布在内蒙古、河北省及河南省等地,已发现镍矿床(点)19处,其中大型矿床1处,中型矿床3处,小型矿床8处,矿点7处.新元古代和晚古生代是华北地区镍矿床形成的2个高峰期.矿床类型以岩浆型为主,其次为风化壳型和沉积变质型.沉积变质型镍矿床主要产在华北陆块区内,形成环境与裂陷盆地有关;岩浆型和风化壳型...     

A review of mineral resources in Malawi: With special reference to aluminium variation in mineral deposits

The lithology of Malawi is characterized by Precambrian metamorphic and igneous rocks which form part of the polyphase East African Orogen. Rift-related sedimentation and igneous activity during the late Paleozoic (Karoo System) and the late Mesozoic (Chilwa Province) have produced a great variety of rocks that underwent strong chemical weathering and erosion when the entire region received its final shape by peneplanation and fluvial incision during the Cenozoic under (sub)tropical climatic conditions. Aluminum is a dominating element in minerals (e.g., corundum, kyanite, beryl, gibbsite) in this region. Some minerals were concentrated in deposits bound to Al-enriched host rocks (zircon, pyrochlore, eudialyte, uranium minerals) with high A/CNK ratios, whereas others, e.g., asbestos, chalcedony, monazite, kaolinite, ilmenite and garnet have host rocks of a low A/CNK ratio. Aluminum was used to categorize these various mineral deposits. The abundance of aluminum and accumulations of Nb, Zr, Ti, REE, Sr and Ba point for some mineralisations to similar subcrustal carbonatite-forming systems that were operative during periods of the Precambrian and the Mesozoic in Malawi. Aluminum variation does not only reflect differentiation in the various igneous rock series but it is also visible in the sedimentary realm during transport and weathering. In context with other elements such as Ti and P, Al provides an opportunity to reveal chemical relationships between rocks and mineral deposits. Spinel and Al-enriched silicate minerals can be used as pathfinder minerals in the stream sediments to guide the exploration geologist to non-metallic deposits.     

山东省矿产资源类型和时空分布特点

山东省矿产资源丰富,矿业工业总产值居全国第4位。文章通过对矿产资源类型、分布、成矿地质体和成矿时代等的分析与归纳,概要总结了山东省主要矿产资源成矿规律。将矿床成因类型划分为岩浆型、伟晶岩型、斑岩型、接触交代型、热液型、陆相火山岩型、海相沉积型、陆相沉积型、沉积变质型和风化壳型10种;在全国Ⅰ-Ⅲ级成矿区带划分的基础上,按照山东省矿产资源分布规律将其划分了6个成矿亚区(Ⅳ)、14个成矿小区(Ⅴ级)和52个矿床集中区(Ⅵ级),概略分析了各成矿亚区地质、矿产资源简况;将成矿时代划分为新太古代、古元古代、古生代、中生代和新生代5个主要成矿期,总结了各成矿期的矿产资源类型。对成矿的关键科学问题进行了初步讨论,尤其是针对具有全球意义的胶东金矿成矿的特殊性进行了分析,提出了中生代斑岩型铜、钼矿床和热液型金矿床的找矿新思路。     

Possible ways to decipher spatial distribution of mineral resources

Regularity of structural patterns can be connected to planetary disjunctive systems (paleosystems). A computerized universal model of these systems should be developed that may be helpful to predict unknown localities of mineral resources controlled by tectonic processes. The specific character of tectonic phenomena is to be respected in geomathematical models. Some suggestions for applications are given.     

几内亚优势金属矿产地质特征、成矿作用及开发现状

几内亚大地构造位置处于西非克拉通南部,主要受Libérien、Eburnéen及泛非三次大的造山运动影响,主要的地质单元包括东部太古宙—古元古代马莱地盾、西部古生代博法(Bove)盆地和西南部泛非期Rokelide造山带。在广泛调研文献的基础上,着重介绍了几内亚铝土矿、铁、金等矿产资源的开发现状。结合区域地质背景和典型矿床分析,剖析了这3种优势金属矿产的成矿作用,认为几内亚超大规模的铝土矿资源是地质历史时期区域构造、成矿母岩、气候、地形地貌、水文地质等多种因素耦合作用的结果。几内亚拥有世界上规模最大的未开发BIF型铁矿资源,主要分布在几内亚东南部宁巴山和西芒杜2条绿岩带上,BIF型铁矿经历了太古宙至今漫长的沉积-变质/变形-风化富集作用。几内亚金矿以造山型金矿为主,形成于Eburnean造山运动晚期(2102~2085 Ma),主要分布在北部锡几里盆地内,具有明显的构造和岩性控矿特征。     

Metallic mineral deposits

Except for the fringing reef, the limestones of Christmas Island in the Indian Ocean are of Late Eocene (Tertiary “b") and Early Miocene (Tertiary “e” to “f") age. The Upper Eocene limestone is an algal limestone containing Discocyclina, Nummulites, and Heterostegina. The Lower Miocene limestone is an algal limestone containing in its lower part species of Lepidocyclina (Eulepidina) followed by Miogypsinoides dehaarti. Miogypsinoides dehaarti extends into the zone of Flosculinella bontangensis. No rocks younger than Burdigalian were identified other than on the fringing reef which contains an assemblage of Pliocene‐Pleistocene Foraminifera.     

The exploitation of off-shore mineral resources

The exploitation of offshore mineral wealth is generally higher cost than from land based developments. Given the availability of adequate resources relative to expected demand, interest in the exploitation of most offshore minerals seems likely to remain minimal. There are two exceptions, viz. first, sands and gravels and second, hydrocarbons. Offshore exploitation of the former is restricted to shallow sea floor deposits close to nearby onshore areas of high demand. Their extraction is a highly localised phenomenon. Offshore hydrocarbons production had similar locational characteristics as extensions of pre-existing onshore developments. Recently, however, offshore hydrocarbons have been increasingly exploited in their own right: in areas where market opportunities made such higher-cost operations economically and/or geo-politically attractive. The North Sea stands out in significance. Here, development has been highly pro-active, in terms of political, technological and entrepreneurial considerations. This has produced a unique geographical phenomenon in the maritime environment which will continue to be important for two more decades, and be extended to other north-west European offshore locations. What remains to emerge is the strength of its demonstration effect elsewhere, where the combination of the highly favourable circumstances of Western Europe for such intensive offshore hydrocarbons activities may not reoccur.     

加拿大拉布拉多地区主要金属矿床地质特征及其时空分布

拉布拉多是加拿大大西洋成矿域中具地质多样性的最大的成矿省,区域成矿地质条件优越,产有Superior型含铁建造、岩浆硫化物、铂族元素、火山成因块状硫化物、铀、稀有稀土等多种金属矿床。文章介绍了拉布拉多铁、铀、稀有稀土、镍多金属等优势金属矿床的成矿背景、成矿特征、矿床(点)分布、典型矿床地质特征及最新勘探成果,分析了区域地质演化作用与区域内主要金属矿床的时空分布。     

吉林省东部贵金属、有色金属矿床的时空分布规律

将吉林省东部地区的贵金属、有色金属矿床在成矿作用时间上与全球性成矿事件及区域性成矿事件对比分析,总结成矿的相似性和本区成矿的特点及具中国特色的燕山期成矿的重要性,提出区内大型矿田(或矿集区)的空间分布特点及主控因素,对成矿预测具指导意义。     

中南部非洲的地质构造演化与矿产分布规律

中南部非洲优势矿产资源有金、铜、铁、铬、金刚石,锰、铀、镍、钒、钴、铂、锑的储量也居世界前列。主要的矿产集中分布于前寒武纪地体内,中南部非洲前寒武纪地体的形成演化决定了矿产的种类和主要成矿类型。文章总结了中南部非洲的地质构造演化以及其主要矿产资源的成矿类型和分布规律,并划分成矿区带至三级。探讨了部分主要成矿区带的成矿规律:太古宙的矿产主要与花岗-绿岩地体有关;古元古代的矿产主要分布于陆缘盆地,与岩浆作用有关;中元古代的矿产主要与岩浆作用有关,次为沉积变质作用;新元古代的矿产主要与沉积变质作用有关,次为岩浆作用。     

闽西南地区大地构造演化和矿床时空分布规律

在充分吸收前人工作成果的基础上,讨论了闽西南地区的主要矿床类型及其特征,将闽西南地区的矿床划分为三个矿床成矿系列:晋宁期与海相火山作用有关的铅、锌、银多金属块状硫化物矿床成矿系列;海西-印支期与火成岩有关的铁、铜、铅、锌多金属矿床成矿系列;燕山期与中酸性火成岩有关的铁、铜、铅、锌、钼、钨、锡、金、银、铀等多金属矿床成矿系列。其中,与燕山期有关的矿床成矿系列可进一步划分为侏罗纪早期与壳幔混合源I型花岗闪长岩有关的铁、铜、铅、锌矿床成矿亚系列;侏罗纪晚期与壳源S型花岗质岩体有关的钨、锡、钼、铋多金属矿床成矿亚系列;早白垩世与壳源型中酸性侵入岩有关的层控矽卡岩型铁、铜、铅、锌、钼多金属矿床成矿亚系列;早白垩世与壳幔混合源型中酸性侵入岩-次火山作用有关的金、银、铜、钼、铅、锌、铀等多金属矿床成矿亚系列。总结研究提出了各成矿(亚)系列的形成背景、时空分布规律,初步认为晋宁期VMS型多金属矿床形成于华南联合陆块拉张裂解形成的政和-大埔海底双峰式火山盆地环境,海西-印支期岩浆热液-斑岩型金属矿床形成于陆内伸展与挤压环境交替出现的岩浆侵入过程中,而燕山期成矿(亚)系列则形成于太平洋构造域时期的陆内伸展与挤压环境交替出现的岩浆侵入与火山喷发的过程中。     

北非重要矿产资源时空分布与典型矿床地质特征

北非地处冈瓦纳与特提斯两大构造域的交汇部位,经历了泛非、海西和阿尔卑斯等多期造山运动,构造、岩浆、变质、热液活动剧烈,为成矿作用创造了优越的地质条件,形成了丰富的金、铜、磷、铁、铬、铅锌、银、铌钽等矿产资源。通过对已有研究成果的梳理总结,发现北非地区最重要且最集中的矿床类型为花岗伟晶岩型矿床、造山带型金银多金属矿床、沉积型磷矿床、MVT型铅锌矿床以及VMS型铜锌金矿床。空间上分布阿特拉斯褶皱带和努比亚造山带,呈现聚集分布的特征。除沉积型矿床成矿时代集中在中生代以外,其他类型矿床主要形成于新元古代。区内典型矿床中,造山型金矿主要与泛非构造运动有关,沉积型磷矿主要受控于海相沉积环境,锡铌钽等稀有金属成矿主要与新元古代晚期花岗伟晶岩密切相关。

     

The concept of multi-criteria mineral resources protection

The author deals with a complex, multi-criteria system of protection of mineral resources, based on the evaluation of their deposits, both with identified and inferred reserves, and perspective areas, i.e., the areas where mineral deposits may occur. The purpose of valorization is to compare different deposits using the same, uniform criteria, and then assign them to particular groups with the intention of protecting the most valuable deposits and highly perspective areas more efficiently. The criteria represent three separate groups: geological and mining assets, the level of certainty (the degree of our knowledge on the mineral raw material and its deposit), as well as environmental and spatial planning constraints. Inclusion of the prognostic areas (the D₁ category of resources in Poland) to the procedure of deposit valorization forms the basis for their legal protection, especially when they have not been protected until now.     

Stochastic modelling of mineral deposits

Mineral deposits are characterized by certain continuity of assay values, thickness and top and bottom surfaces of ore zones etc., which are amenable to stochastic modelling with respect to spatial coordinates. The French School (Matheron, 1963) introduced rather difficult terminology of semi-variogram, kriging etc. for quantitative assessment of reserves and average grade of mining property under the assumption of second-order stationarity of first differenced (d=1) data. A more general, powerful and well-known time-domain (spatial) stochastic models (ARIMA (p, d, q); based on Box and Jenkins, 1970, 1976; Anderson, 1976) are introduced herein which include Matheron Model (d=1) as a special case.     

Marine mineral resources

Oceanic manganese nodules, for long the cornucopia of sea floor mineral deposits, have lost much of their economic attractiveness in recent years as a result of depressed metal prices and difficulties surrounding their potential extraction under the Law of the Sea Convention. In their place, commerical interest in mineral deposits within Exclusive Economic Zones has increased, while the scientific world is enamoured with the black smokers discharging at mid–ocean ridges and the polymetallic sulphides that precipitate from them.