孟连回林低温热液构造角砾岩型金多金属矿

对矿化蚀变带进行分析研究,矿床位于中-下石炭统接触裂隙破碎带中,总结成矿规律,建立找矿标志,为该区的地质找矿指明方向。     

地面高精度磁测在印尼滨海型磁铁矿应用

综合运用低纬度化极与建立模型正演等数据处理手段进行隐伏矿体预测,发现与成矿有关的磁异常,显示良好成矿前景。钻孔证实有工业矿体。     

云南安宁禄脿小村锰铁矿矿床成因及找矿标志

昆阳群美党组军哨段中亚段第二层砂质板岩为铁锰矿源层,严格受地层层位控制,具有后期改造特征,属沉积—改造—层控矿床。     

黑色岩系中海底热液SEDEX矿床的研究概况

黑色岩系是含硫化物和有机质较高的暗色泥质岩、硅岩、碳酸盐岩组合,黑色岩系中以海底热液喷流作用形成的矿床是国际研究热点。因为海陆变化、壳幔作用以及全球构造变动均导致黑色岩系和SEDEX矿床的演化,所以研究湘黔张家界—遵义地区有机物从保存、埋藏、生烃、排气到过成熟,均与微生物的生命代谢、内生地质作用、成矿机制同步谐动,地球化学影响和生物成矿作用与全球性的气候变迁、缺氧事件相关联,而且以上研究集中体现在事件地质学的成因解释、热水喷流沉积作用、生物矿化与金属矿化、矿物成因与环境影响、铂族元素矿物、黑色页岩石煤与金属矿化、元素地球化学影响等方面。研究数据充分显示了特定的地质背景、成矿环境、生物作用机制在黑色岩系SEDEX矿床成岩成矿中的作用。     

矿床学研究思路的变化与进展综述

矿床学的发展突破在很大程度上取决于其研究思路的发展变化上。矿床学从传统的对单一矿种、单一矿床和单一成矿模式的研究发展到对成矿系列、成矿系统的全面探讨和整体认识,妥善处理了局部与整体、片面与全面、个体与群体、定性与定量、时间与空间等种种复杂关系,这种研究思路上的变化体现了系统的、辨证的哲学思维方法。     

广西龙州地区双层含铝岩系地质特征与找矿意义

对龙州地区合山组和都安组铝土岩（矿）层进行系统采样分析，并与堆积铝土矿进行对比研究，结合含铝岩系岩性与矿物特征发现，合山组、都安组铝土岩（矿）矿石矿物无显著差异，主要为一水硬铝石、高岭石、（鲕）绿泥石，其次为赤铁矿（针铁矿）集合体和碎屑物（岩屑、玻屑、砾屑），普遍存在大量（铁）凝胶。常量、微量、稀土元素特征及相关图解显示，合山组、都安组铝土岩（矿）均可能为该区堆积铝土矿的矿源层。Ni-Cr图解显示合山组铝土岩（矿）可能来自与火山物质有关的玄武岩，都安组铝土岩（矿）来源于卡斯特岩溶，堆积铝土矿除部分落入玄武岩、碳酸盐岩区以外，大多位于页岩、板岩内，表明该区堆积铝土矿存在多源性。微量元素Be、Ga、Sr、Ba含量与Sr/Ba、V/Zr、Zr/Cu含量比值等沉积环境元素特征表明该区原生铝土岩（矿）沉积环境为陆相；δCe分析显示铝土岩（矿）沉积环境有所差异，合山组表现为氧化环境，都安组则表现为还原环境。Th、U含量及Th/U含量比值显示该区铝土岩（矿）成矿以混合作用为主，并经历了较强的风化作用；δEu分析表明合山组、都安组铝土岩（矿）分别形成于被动大陆边缘与活动大陆边缘。合山组、都安组含铝岩系均发育不同程度的铝土岩（矿）层，都安组铝土岩（矿）部分样品已达工业边界指标，可作为沉积铝土矿勘查的主要目的层。     

Timing and duration of growth hiatuses in mid Holocene massive Porites corals from the northern South China Sea

Growth hiatuses in massive corals are usually indicative of past ecological or environmental stresses. Among 37 fossil Porites colonies surveyed from the reef flat of Dadonghai fringing reef at Sanya, Hainan Island, northern South China Sea, seven of them were found to show clear evidence of past mortality, representing a population of ～19%. Among these samples, two of them (SYO‐13 and SYO‐28) display clear growth hiatuses reflecting mortality followed by subsequent recruitment, and five others exhibit a well‐preserved mortality surface and no subsequent recruitment. The growth hiatuses were dated using high‐precision thermal ionisation mass spectrometry U‐series techniques. The age results suggest all the dated corals formed and died in the mid Holocene. Multiple dates below the growth hiatuses suggest that SYO‐13 and SYO‐28 died at 6298 ± 11 and 6929 ± 19 a BP (i.e. years before AD 1950), respectively. Multiple dates above the growth hiatuses indicate that growth in SYO‐13 and SYO‐28 resumed at 6257 ± 14 and 6898 ± 20 a BP, respectively. The calculated durations of growth hiatuses are therefore 41 ± 18 a for SYO‐13 and 31 ± 28 a for SYO‐28, respectively, implying growth resumed within decades after the mortality events. U‐series dating of four other samples with dead heads suggests that they died at 6035 ± 53, 6059 ± 23, 6127 ± 22 and 6474 ± 24 a BP, respectively. In addition, using solution inductively coupled plasma mass spectrometry (ICP‐MS), monthly resolution Sr/Ca and Mg/Ca ratios were determined for the annual growth bands below and above the growth hiatuses for three of the dated samples. The Sr/Ca and Mg/Ca profiles indicate that the three corals probably died in different seasons (from spring to autumn), and the mortality appears to be unrelated to anomalous sea surface temperature‐induced bleaching. Copyright © 2010 John Wiley & Sons, Ltd.     

Collocation-PECE�㷨�ڵ͹����Ǿ��ܶ����е�Ӧ��

???????????У?PECE????????????????????????????Collocation????????????????幫??????????μ?PECE???????????????????ж??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????Adams-PECE????????PECE?????????????????????????????,???????????Collocation-PECE??????????????н???????????????Ч??     

赣南中生代橄榄玄粗岩系列厘定的地质证据

本文对赣南会昌地区赣州群茅店组底部的中基性火山岩的矿物岩石-地球化学进行了系统研究对比。根据岩石具高K_2O/Na_2O值(>1.0)、Na_2O+K_2O(>5％)含量、氧化系数(O_x>0.5),低TiO_2含量(<1％)、SiO_2饱和度(CIPW标准矿物Q<3％),贫铁,以及富集亲石元素(Rb、Sr、Ba、Th等)和轻稀土元素等特征,结合岩石基质中存在大量钾长石微晶、斜长石斑晶具钾长石环边及偶见橄榄石斑晶等矿物学特点,确定会昌地区火山岩属橄榄安粗岩系,岩石为橄榄玄粗岩-安粗岩-粗面岩组合。采用Rb-Sr等时线法厘定火山岩的同位素年龄为108Ma。首次证实在华南板块内部存在中生代橄榄玄粗岩系。