宁蒗铜厂河铜矿床成矿条件研究

宁蒗铜厂河铜矿床系喜马拉雅期隐伏斑岩体外接触带玄武岩系热液型铜矿床，其主要含矿层位为上二叠统玄武岩组三段（P2β^3）与黑泥哨组（P2h)，主干控矿构造为南北向断裂体系，铜矿化均产于NW向F1断裂的下盘（南盘）。矿区具显著的成矿多期，多阶段性和矿化体水平，垂直分带性规律，通过对碳，氧，硫等稳定同位素和包裹体分析及成矿热液演化特征探讨，建立了铜矿热液成矿模式。     

中间主应力对共轭平移断层中各序次应力场和断裂等构造形迹相互关系的影响

从数学力学的角度定量分析了考虑中间主应力的影响时各类构造结构面之间的空间组合规律,并推导出相关的公式。首次提出了考虑中间主应力的影响时在预测或预报对区域稳定性或岩体稳定性具有重大影响的断裂构造的产状要素和派生构造应力场的方位和大小的方法。计算结果表明:中间主应力对构造结构面之间的空间组合规律具有重要影响。     

Master of the Obscure—Automated Geostatistical Classification in Presence of Complex Geophysical Processes

The topic of this paper is the retrieval of hidden or secondary information on complex spatial variables from geophysical data. Typical situations of obscured geological or geophysical information are the following: (1) Noise may disturb the signal for a variable for which measurements have been collected. (2) The variable of interest may be obscured by other geophysical processes. (3) The information of interest may formally be captured in a secondary variable, whereas data may have been collected for a primary variable only, that is related to the geophysical process of interest. Examples discussed here include mapping of marine-geologic provinces from bathymetric data, identification of sea-ice properties from snow-depth data, analysis of snow surface data in an Alpine environment and association of deformation types in fast-moving glaciers from airborne video material or satellite imagery. Data types include geophysical profile or trackline data, image data, grid or matrix-type data, and more generally, any two-dimensional or three-dimensional discrete or discretizable data sets. The framework for a solution is geostatistical characterization and classification, which typically involves the following steps: (1) calculation of vario functions (which may be of higher order or residual type, or combinations of both), (2) derivation of classification parameters from vario functions, and (3) characterization, classification or segmentation, depending on the applied problem. In some situations, spatial surface roughness is utilized as an auxiliary variable, for instance, roughness of the seafloor may be derived from bathymetric data and be indicative of geological provinces. The objective of this paper is to present components of the geostatistical classification method in a summarizing and synoptical manner, motivated by applied examples and integrating principal and generalized concepts, such as hyperparameters and parameters that relate to the same physical processes and work for data in oversampled and undersampled situations, parameters that facilitate comparison among different data types, data sets and across scales, variograms and vario functions of higher order, and deterministic and connectionist classification algorithms.     

Megacrysts from the Grib kimberlite pipe (Arkhangelsk Province, Russia)

The megacryst suite of the Grib kimberlite pipe (Arkhangelsk province, Russia) comprises garnet, clinopyroxene, magnesian ilmenite, phlogopite and garnet-clinopyroxene intergrowths. Crystalline inclusions, mainly of clinopyroxene and picroilmenite, occur in garnet megacrysts. Ilmenite is characterized by a wide range in the contents of MgO (10.6–15.5 wt.%) and Cr₂O₃ (0.7–8.3 wt.%). Megacryst garnets show wide variations in Cr₂O₃ (1.3–9.6 wt.%) and CaO (3.6–11.0 wt.%) but relatively constant MgO (15.4–22.3 wt.%) and FeO (5.2–9.9 wt.%). The pyroxenes also show wide variations in such oxides as Cr₂O₃, Al₂O₃ and Na₂O (0.56–2.95; 0.86–3.25; 1.3–3.0 wt.%, respectively). The high magnesium and chromium content of all these minerals puts them together in one paragenetic group. This conclusion was confirmed by studies of the crystalline inclusions in megacrysts, which demonstrate similar variations in composition. Low concentration of hematite in ilmenite suggests reducing conditions during crystallization. P–T estimates based on the clinopyroxene geothermobarometer (Contrib. Mineral. Petrol. 139 (2000) 541) show wide variations (624–1208 °C and 28.8–68.0 kbars), corresponding to a 40–45 mW/m² conductive geotherm. The majority of Gar-Cpx intergrowths differ from the corresponding monomineralic megacrysts in having higher Mg contents and relatively low TiO₂. The minerals from the megacryst association, as a rule, differ from the minerals of mantle xenoliths, but garnets in ilmenite-bearing peridotite xenoliths are compositionally similar to garnet megacrysts. The common features of trace element composition of megacryst minerals and kimberlite (they are poor in Zr group elements) suggest a genetic relationship. The origin of the megacrysts is proposed to be genetically connected with kimberlite magma-chamber evolution on the one hand and with associated mantle metasomatism on the other. We suggest that, depending on the primary melt composition, different paragenetic associations of macro/megacrysts can be crystallized in kimberlites. They include: (1) Fe–Ti (Mir, Udachnaya pipes); (2) high-Mg, Cr (Zagadochna, Kusova pipes); (3) high-Mg, Cr, Ti (Grib pipe).     

福建福清黄塘硅质岩时代讨论及其意义

前人区调资料将福清黄塘地区发育的硅质岩划分为晚侏罗世长林组,但没有确切的时代证据。经调查研究,从岩石面貌、岩性组合、地球化学特征及沉积背景等方面进行区域对比,将该套硅质岩划为早三叠世溪口组角岩段。该地区早三叠世地层的发现对重新认识福建沿海乃至台湾海峡地区古生代一早三叠世的地质构造背景意义重大。     

超镁铁岩建造中的非金属矿床组合及其形成条件的研究

超镁铁岩建造中赋存着以镁质非金属矿物为主的多种非金属矿产和丰富多样的矿床共生组合。本文讨论了我国三种主要类型超镁铁岩建造或杂岩(蛇绿岩套中的超镁铁岩建造、碱性超镁铁杂岩、碱性玄武岩及其深源超镁铁岩包体)中产出的非金属矿床及其组合与特征,以及它们的形成条件等,提出了进一步从不同层次深入探讨非金属矿床共生组合的有关问题。     

罗布泊富钾卤水矿床地球化学空间分布特征

罗布泊是我国最重要的成盐成钾盆地之一,富钾卤水资源丰富。在14年的工业开采过程中,不同矿层卤水的地球化学特征持续处于变化中。为了加强对不同矿区富钾卤水的地球化学空间分布特征的认识,合理开发利用卤水资源,本文应用克里金插值法,对2017年采集的89个常观孔卤水样品进行了空间分析,绘制了K~+、Cl~-、Na~+、Mg~(2+)、Li~+、B~(3+)、SO_4~(2-)等值线图,并对其空间分布特征进行了综合分析,结果显示:K~+、Cl~-、Mg~(2+)、Li~+、B~(3+)等离子具有较为一致的分布趋势,其高值区主要分布在罗北凹地及腾龙矿区北部,低值区主要分布于罗北凹地北部及矿区西南部,而SO_4~(2-)分布趋势则相反;由于受周缘地区淡水补给的影响,矿区西南部、北部及东南部出现淡化现象,但是淡水只影响到W_1、W_2层,W_3层未见明显淡化现象;2017年罗布泊矿区K~+平均含量为8.83g/L,除受淡水影响区域外,矿区内大部分地区样品KCl品位均高于1%的工业单独开采品位,与开采前KCl品位相比,目前罗北凹地W_1储层KCl平均品位约下降了9.7%左右。     

内蒙古阿拉善左旗乌兰尚德地区志留系圆包山组笔石化石的发现及其地质意义

阿拉善盟阿拉善左旗杭乌拉山以北哈日奥布日格断凹陷盆地两侧,北东向出露770km2的哑地层,前人将其划为二叠系双堡塘组,但该套地层的岩性和岩石组合及层序特征,与内蒙古岩石地层所述的双堡塘组的现在定义和地质特征及区域变化完全相悖。采用现代沉积学理论和层序地层学方法,开展岩石组合、基本层序、沉积构造与沉积环境研究,划分出3个段级填图单元。根据发现的笔石化石和被晚泥盆世中粗粒黑云母花岗闪长岩侵入的关系,将地层时代确定为早志留世,改划为志留系圆包山组。泥盆纪区域变质变形作用使其发生浅变质和片理化变形,并形成轴向北东的复式向斜构造。后期叠加构造变形,形成紧闭倒转褶皱。志留系圆包山组的确定对本区地层划分和区域构造演化研究有重要意义。     

土壤水溶性有机物吸着系数及其影响因素研究

测定了中国中、东部地区17种土类45个表土样品中水溶性有机物的吸着系数、分子量分布、腐殖酸含量、粘土含量以及土壤pH值，分析了水溶性有机物吸着系数的分布、地域分异和影响吸着系数的主要因素。结果表明，中国中、东部主要天然土壤类型A层水溶性有机物吸着系数在0．0014－0．0284L/g，中位数为0．0062L/g；研究区吸着系数具有自北向南和自西向东递降的一般趋势。水热的地域分异是影响土壤A层Ks地域分异的根本因素，pH和WSOC分子量分布是直接影响Ks值的两个重要因素。     

新疆县域经济空间格局演化特征

通过ESDA空间分析,研究1985年以来新疆县域经济格局在空间上的变化及其特征.结果表明:1985年以来新疆县域经济发展水平表现出较弱的空间自相关性,但集聚作用总体不断增强.热点区的空间结构主要集中在以奎-克-乌为核心的圈形结构,2000年以后热点区显著增加,不断向北疆中部、东疆以及南疆东北部集聚;南疆西南部处于经济发...