会泽金牛厂铅锌矿成矿地质条件

铅锌矿体赋存于下寒武统筇竹寺组八道湾段（∈1q^1）灰黑色中厚层状泥质粉砂岩中;筇竹寺组玉案山段（∈1q^2）灰黄色、灰黑色泥质页岩夹薄层状细砂岩为矿区成矿的隔挡层。北东向的关仓箐逆断裂为矿区的导矿构造,北西西向次级张扭性断裂和北北东向层间断裂为矿区的容矿构造。     

云南双江白水河金矿成矿地质特征

白水河金矿属断裂构造控制的热液蚀变型金矿床,金矿体产于新元古界澜沧群变质岩区多期断裂的次级分支断裂破碎带内。沿构造带有辉绿岩脉、石英斑岩脉、煌斑岩脉侵入,首次在临沧地区新元古界澜沧群变质岩区找到金矿。     

Geochemical Characteristics and Genetic Significance of Datangpo‐Type Manganese Ore Deposits during the Cryogenian Period

The Datangpo‐type manganese ore deposits, which formed during the Nanhuan (Cryogenian) period and are located in northeastern Guizhou and adjacent areas, are one of the most important manganese resources in China, showing good prospecting potential. Many middle‐to‐large deposits, and even super‐large mineral deposits, have been discovered. However, the genesis of manganese ore deposits is still controversial and remains a long‐standing source of debate; there are several viewpoints including biogenesis, hydrothermal sedimentation, gravity flows, cold‐spring carbonates, etc. Geochemical data from several manganese ore deposits show that there are positive correlations between Al₂O₃ and TiO₂, SiO₂, K₂O, and Na₂O, and strong negative correlations between Al₂O₃ and CaO, MgO, and MnO in black shales and manganese ores. U, Mo, and V show distinct enrichment in black shales and inconspicuous enrichment in Mn ores. Ba and Rb show strong positive correlations with K₂O in manganese ores. Cu, Ni, and Zn show clear correlations with total iron in both manganese ores and black shales. ∑REE of manganese ores has a large range with evident positive Ce anomalies and positive Eu anomalies. The Post Archean Australian Shale (PAAS) normalized rare earth element (REE) distribution patterns of manganese ores present pronounced middle rare earth element (MREE) enrichment, producing “hat‐shaped” REE plots. ∑REE of black shales is more variable compared with PAAS, and the PAAS‐normalized REE distribution patterns appear as “flat‐shaped” REE plots, lacking evident anomaly characteristics. δ¹³C values of carbonate in both manganese ores and the black shales show observable negative excursions. The comprehensive analysis suggests that the black shales formed in a reducing and quiet water column, while the manganese ores formed in oxic muddy seawater, which resulted from periodic transgressions. There was an oxidation–reduction cycle of manganese between the top water body and the bottom water body caused by the transgressions during the early Datangpo, which resulted in the dissolution of manganese. Through the exchange of the euphotic zone water and the bottom water, and episodic inflow of oxygenated water, the manganese in the bottom water was oxidized to Mn‐oxyhydroxides and rapidly buried along with algae. In the early diagenetic stage, Mn‐oxyhydroxides were reduced and dissolved in the anoxic pore water and then transformed into Mn‐carbonates by reacting with HCO₃^? from the degradation of organic matter or from seawater. In the intervals between transgressions, continuous supplies of terrigenous clastics and the high productive rates of organic matter in the euphotic zone resulted in the deposition of the black shales enriched in organic matter.     

云南富宁地区铜镍矿成矿地质条件分析

铜镍是富宁地区主要矿种。成矿母岩为"安定型"基性岩。岩体具有明显的分异现象,自边缘至中心可分成致密状辉绿岩相、中细粒橄榄辉长苏长岩相、中粒辉长苏长岩相、中粒闪长岩相四个相带。铜镍矿主要产于中细粒橄榄辉长苏长岩相中,其次产于中粒辉长苏长岩相中。对富宁地区铜镍矿成矿地质条件进行分析。     

西藏尼木斑岩铜多金属矿区后续地质勘查思考

根据前期勘查结果,岗讲Ⅰ号矿体品位偏低,矿体厚度、产状变化较大,形态较复杂,应加强矿区基础地质工作,综合地质研究工作,总结铜、钼空间富集规律,建立成矿模式,指导矿区深部及外围找矿的合理化布局。     

差异流动变形破坏研究

工程岩体出现许多流变现象, 它最突出的特点是差异流动变形破坏。本文从流变现象及变形量测结果论述差异流动变形破坏特征, 并且根据蠕变流动变形破坏与时间的关系进行了差异流动变形分类, 这些类型同时存在于一个岩体或岩块内。     

呵叻盆地钾镁盐矿沉积特征及成因探讨

充分收集已有地质成果基础上，分析呵叻盆地沉积特征和成钾条件。详细论述呵叻盆地钾盐矿的赋存条件和产出特征，初步探讨钾盐矿的形成机理。     

云南省施甸县摆田铅锌矿矿床地质特征及成因

矿体赋存于上三叠统大水塘组顶部与中三叠统河湾街组底部断层接触带中,严格受构造控制.矿体呈透镜状～似层状,厚度变化较大.为一早期形成于断裂破碎带中后经地表长时间氧化淋滤叠加形成的热液—风化淋滤型铅锌矿床.     

云南大理洱源腊坪岩浆岩风化壳型钛铁砂矿

腊坪地区TiO2区域高值,有利于钛铁矿形成富集。对三类主要岩浆岩中TiO2含量与重砂淘洗砂矿样含矿率比照,认为辉长岩是钛铁砂矿含矿母岩,且与地形地貌及风化次生堆积条件有关。     

地电前兆异常特征及澜沧—耿马7.6级等地震预报问题

深入研究了全国地电台网内M_s≥5.0的45次地电前兆震例,用统计方法按大震、强震、中强地震分别研究其地电前兆特征。 通过研究得到:大震地电阻率异常范围,其半径超过200km,在700km以内,异常时间在12—20个月内发震的概率最高,为97.8％;强震地电阻率异常范围大多在300km以内,趋势异常的时间在12个月以内发震的概率最高,为86.5％;中强地震地电阻率异常范围,半径一般在200km以内,趋势异常时间在180天之内发震的概率最高,为95.0％。大震、强震、中强地震地电趋势异常时间似乎存在着20个月、12个月、6个月三个不同的异常时间段。 临震异常类型一般可分为加速型、转向型和波动型三类。对7级和7级以上大震能观测到临震异常前兆的震例只有33.3％、强震和中强地震能观测到临震异常前兆的震例均为50.0％。出现临震异常后1—20天发震的概率最高,达94.4％。 1988年11月以来,西部地区先后发生澜沧-耿马7.6、巴塘6.7、天祝6.2级地震。震前都曾依据地电前兆短临异常特征,作过某种程度的监测预报工作,取得了较好的短临预报效果。