地下水采样技术及《地下水采样技术规程》的编制

地下水取样是地下水调查、监测中的一项关键技术工作,必须要根据调查场地的条件和调查的目的选择合适的采样方法,并严格按照操作规程进行采样,以取得真实、有代表性的样品。本文在梳理常用地下水采样方法和采样器具的基础上,介绍了行业标准《地下水采样技术规程》的编制过程及其主要内容。该规程内容涉及地下水现场测试样品、无机检测样品、有机检测样品、气体检测样品、同位素检测样品、专项样品（包括地热水样品和饮用矿泉水样品）等的采集要求、采样方法、样品保存、质量控制等。     

德兴朱砂红矿床含辉钼矿岩石样品Re_Os定年及地质意义

辉钼矿中Re、Os含量高且几乎不含普通Os,通常被认为是开展金属矿床定年的理想对象。然而,在一些矿床中辉钼矿常以浸染状产出,矿物颗粒微小,挑纯难度较大,本文尝试使用含辉钼矿的岩石样品进行测年实验。选择研究程度较高、年龄数据较多的德兴斑岩铜矿田朱砂红矿床的4件含辉钼矿岩石样品进行了Re_Os同位素定年,结果获得等时线年龄为172.6±2.6 Ma,与前人已获得的年龄数据基本一致,说明该年龄数据可靠,样品中的硅酸盐矿物对定年结果没有影响。德兴斑岩铜矿田中3个矿床的辉钼矿Re_Os年龄与花岗闪长斑岩的锆石U_Pb年龄相一致,表明其矿化与斑岩侵入体直接相关。而前人获得的Rb_Sr年龄及K_Ar年龄与近年得到的Re_Os、U_Pb年龄数据存在差别的原因可能是后期热液蚀变及热事件破坏或重置了Rb_Sr和K_Ar同位素体系。     

发射光谱法同时测定地球化学样品中微量银铍硼锡铋钼

采用垂直电极装样,二米平面光栅交流电弧摄谱测定地质样品中的微量元素银、铍、硼、锡、铋、钼,以三氧化二铝、焦硫酸钾、氟化钠、碳粉和硫粉作缓冲剂,锑、锗作内标。方法检出限为:银0.019μg/g、铍0.11μg/g、硼0.85μg/g、锡0.26μg/g、铋0.031μg/g、钼0.12μg/g。各元素12次测定的相对标准偏差(RSD)均小于10%。用水系沉积物、土壤、岩石国家一级标准物质进行验证,测定值与标准值基本一致,符合多目标地球化学填图的质量要求。     

Assessing volcanic origins within detrital zircon populations——A case study from the Mesozoic non-volcanic margin of southern Australia

Detrital zircon U/Pb geochronology is a common tool used to resolve stratigraphic questions,inform basin evolution and constrain regional geological histories.In favourable circumstances,detrital zircon populations can contain a concomitant volcanic contribution that provides constraints on the age of deposition.However,for non-volcanic settings,proving isolated detrital zircon grains are from contemporaneous and potentially remote volcanism is challenging.Here we use same grain(U-Th)/He thermochronology coupled with U/Pb geochronology to identify detrital zircon grains of contemporary volcanic origin.(U-Th)/He ages from Cretaceous zircon grains in southern Australia define a single population with a weighted mean age of 104±6.1 Ma.indistinguishable from zircon U/Pb geochronology and palynology(～104.0-107.5 Ma).Detrital zircon trace-element geochemistry is consistent with a continental signature for parent rocks and coupled with detrital grain ages,supports derivation from a2000 km distant early-to mid-Cretaceous Whitsunday Volcanic Province in eastern Australia.Thus,integration of biostratigraphy,single-grain zircon double-dating(geochronology and thermochronology)and grain geochemistry enhances fingerprinting of zircon source region and transport history.A distal volcanic source and rapid continental-scale transport to southern Australia is supported here.     

加速溶剂萃取技术在油气化探样品稠环芳烃测定前处理中的应用

油气化探样品测定芳烃物质的提取方法通常采用振荡提取,在实际的样品测试过程中,这种前处理方法效率较低,得到的提取液用于分析测定的结果重现性较差。本文对油气化探样品稠环芳烃的提取方法进行改进,采用加速溶剂萃取技术,对实际样品进行试验,考察了压力、静态萃取时间和萃取温度对稠环芳烃萃取效率的影响,确定最佳的萃取条件为: 萃取压力8.3 MPa,静态时间5 min,萃取温度80 ℃。对比了加速溶剂萃取与传统振荡提取应用于油气化探样品前处理的提取效率,证实了加速溶剂萃取技术可以显著提高萃取效率,稠环芳烃的荧光强度提高60.5%~152.6%,方法的稳定性好,测定结果的精密度高,相对标准偏差(RSD, n=7)低于4%。加速溶剂萃取技术优于传统振荡法,更能满足油气化探样品分析测试的准确度与精密度要求,可以应用于油气化探样品前处理过程。     

广东省金属矿床成矿系列及成矿历史演化

广东省金属矿床划分为５个矿床成矿系列,分别论述各成矿系列的基本特征和主要成矿元素在地质历史中的演化特点,并分析了区域成矿物质来源和成矿演化与区域变质作用、重熔岩浆活动、构造演化的关系。     

Magmatic changes during the stabilisation of a cordilleran fold belt: the Late Carboniferous–Triassic igneous history of eastern New South Wales, Australia

In a 60 Ma interval between the Late Carboniferous and the Late Permian, the magmatic arc associated with the cordilleran-type New England Fold Belt in northeast New South Wales shifted eastward and changed in trend from north–northwest to north. The eastern margin of the earlier (Devonian–Late Carboniferous) arc is marked by a sequence of calcalkaline lava flows, tuffs and coarse volcaniclastic sedimentary rocks preserved in the west of the Fold Belt. The younger arc (Late Permian–Triassic) is marked by I-type calcalkaline granitoids and comagmatic volcanic rocks emplaced mostly in the earlier forearc, but extending into the southern Sydney Basin, in the former backarc region. The growth of the younger arc was accompanied by widespread compressional deformation that stabilised the New England Fold Belt. During the transitional interval, two suites of S-type granitoids were emplaced, the Hillgrove Suite at about 305 Ma during an episode of compressive deformation and regional metamorphism, and the Bundarra Suite at about 280 Ma, during the later stages of an extensional episode. Isotopic and REE data indicate that both suites resulted from the partial melting of young silicic sedimentary rocks, probably part of the Carboniferous accretionary subduction complex, with heat supplied by the rise of asthenospheric material. Both mafic and silicic volcanic activity were widespread within and behind the Fold Belt from the onset of rifting (ca. 295 Ma) until the reestablishment of the arc. These volcanic rocks range in composition from MORB-like to calcalkaline and alkaline. The termination of the earlier arc, and the subsequent widespread and diverse igneous activity are considered to have resulted from the shallow breakoff of the downgoing plate, which allowed the rise of asthenosphere through a widening lithospheric gap. In this setting, division of the igneous rocks into pre-, syn-, and post-collisional groups is of limited value.     

沧参1井热历史及成油气环境研究

本文通过Ｕ－Ｐｂ同位素地质年代学研究，指出沧参１井沉积地层中的物质来源是华北古陆；隐伏花岗岩侵位年龄为９９Ｍａ，来源于具下地壳特征的太古宙岩石的重熔。对奥陶系碳酸岩流体包裹体特征研究指出沧参１井流体包体类型可分为３大类、８个亚类，本区碳酸盐类岩石有机质丰富，应为一套生油储油较好的岩系。特别是通过不同深度１０个磷灰石样品裂变径迹表观年龄和径迹长度特征的研究，论述了本区古地温的变化，约在１４３Ｍａ前石炭二送纪地层中的磷灰石经历过完全的退火，这是二迭纪以下地层的第１次生油作用；９９Ｍａ花岗岩侵位，岩浆热对围岩中有机质的转化和油气的形成起了促进作用，这可作为第２次生油期；第三纪时因地壳下降，沉积了巨厚的第三系地层，这时磷灰石退火带范围（大致相当于生油带）约为１７００—３９００ｍ，古地温梯度为３．１℃／１００ｍ，这是本区第３次生油阶段。     

冻土断裂韧度KIC尺寸效应实验研究

采用三点弯曲试验研究了冻土断裂韧度ＫＩＣ的尺寸效应，应用Ｗｅｉｂｕｌｌ脆性破坏统计理论获得了反映冻土ＫＩＣ尺寸效应的材料常数，即尺寸效应系数α。应用α值进行ＫＩＣ值理论预测，与实测值相比，其最大误差不超过５％。