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51.
通过因子分析、相关分析和聚类分析,研究了巴彦温多尔金矿矿石和围岩样品12种元素的组合特征。结果显示,矿石中金与其他11种元素的相关程度很低,而围岩中金与银有较强的相关性。围岩和矿石的元素组合也有明显差别,围岩样品代表控矿构造带的矿化背景,矿石样品代表成矿时的元素组合。 相似文献
52.
磁力勘探与岩性测深理论基础的对比 总被引:1,自引:0,他引:1
首先概括了岩性测深技术的理论基础和物性基础要点,强调电偶极子场是岩性测深技术的基本理论。然后通过电偶极子场与磁偶极子场的类比,以及岩性测深与磁力勘探的对比,提出了一条研究岩性测深技术理论基础及正演计算的思路。 相似文献
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交会图和Carbon软件在火山碎屑岩识别中的应用 总被引:1,自引:0,他引:1
针对火山岩储层的特殊性(复杂性、离散性和随机性),应用交会图及Carbon软件对火山岩测井解释中岩性识别问题进行了研究。该方法的技术关键是交会图的选取,以交会图和Carbon软件为基础实现对岩性的识别。将研究方法应用在海拉尔地区火山碎屑岩岩性识别问题中,取得了很好的效果,岩性解释符合率80%。 相似文献
55.
胶南造山带榴辉岩中的高压、超高压变质矿物主要有绿辉石、镁铝榴石、柯石英、金刚石、金红石等。柯石英、金刚石均呈微晶状包裹于石榴子石、绿辉石中。柯石英多已转化为石英聚晶,并使包裹它的矿物产生放射状胀裂纹;金刚石呈近等轴八面体等,其形成压力达3.5GPa以上。榴辉岩围岩中的高压、超高压变质矿物主要有辉石类(透辉石、霓石、暗硬玉)、钠钙质钠质角闪石(钠闪石、镁钠闪石)、多硅白云母(3T型)、钠长石、绿帘石等。高压、超高压变质矿物的广泛出现指示区内存在两期高压变质作用:早期为超高压榴辉岩相变质作用;晚期为高压绿片岩相榴辉岩相变质作用。华北板块与扬子板块的多次碰撞是区内高压、超高压变质作用产生的主要原因。 相似文献
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内蒙额尔古纳在矿带中生代火山岩浆活动与金属成矿的关系 总被引:1,自引:0,他引:1
在岩石学和微量元素地球化学研究的基础上,通过对不同类型矿床的成矿岩体及围岩条件的分析,探讨了中生代火山岩浆活动与金属成矿的关系。认为晚侏罗世火山岩浆活动为成矿提供了有利的围岩的构造空间;早白垩世岩浆活动提供了成矿岩体及热力学条件,该期次火山岩浆的侵入并作用于不同的围岩、形成了由斑岩型Cu、Mo矿,浅成熟液型Ag、Pb、Zn矿等组成的一系列矿床组合。 相似文献
58.
The Kos Plateau Tuff consists of pyroclastic deposits from a major Quaternary explosive rhyolitic eruption, centred about 10 km south of the island of Kos in the eastern Aegean, Greece. Five main units are present, the first two (units A and B) were the product of a phreatoplinian eruption. The eruption style then changed to `dry' explosive style as the eruption intensity increased forming a sequence of ignimbrites and initiating caldera collapse. The final waning phase returned to phreatomagmatic eruptive conditions (unit F). The phreatomagmatic units are fine grained, poorly sorted, and dominated by blocky vitric ash, thickly ash-coated lapilli and accretionary lapilli. They are non-welded and were probably deposited at temperatures below 100°C. All existing exposures occur at distances between 10 km and 40 km from the inferred source. Unit A is a widespread (>42 km from source), thin (upwind on Kos) to very thick (downwind), internally laminated, dominantly ash bed with mantling, sheet-like form. Upwind unit A and the lower and middle part of downwind unit A are ash-rich (ash-rich facies) whereas the upper part of downwind unit A includes thin beds of well sorted fine pumice lapilli (pumice-rich facies). Unit A is interpreted to be a phreatoplinian fall deposit. Although locally the bedforms were influenced by wind, surface water and topography. The nature and position of the pumice-rich facies suggests that the eruption style alternated between `wet' phreatoplinian and `dry' plinian during the final stages of unit A deposition.Unit B is exposed 10–19 km north of the inferred source on Kos, overlying unit A. It is a thick to very thick, internally stratified bed, dominated by ash-coated, medium and fine pumice lapilli in an ash matrix. Unit B shows a decrease in thickness and grain size and variations in bedforms downcurrent that allow definition of several different facies and laterally equivalent facies associations. Unit B ranges from being very thick, coarse and massive or wavy bedded in the closest outcrops to source, to being partly massive and partly diffusely stratified or cross-bedded in medial locations. Pinch and swell, clast-supported pumice layers are also present in medial locations. In the most distal sections, unit B is stratified or massive, and thinner and finer grained than elsewhere and dominated by thickly armoured lapilli. Unit B is interpreted to have been deposited from an unsteady, density stratified, pyroclastic density current which decelerated and progressively decreased its particle load with distance from source. Condensation of steam during outflow of the current promoted the early deposition of ash and resulted in the coarser pyroclasts being thickly ash-coated. The distribution, texture and stratigraphic position of unit B suggest that the pyroclastic density current was generated from collapse of the phreatoplinian column following a period of fluctuating discharge when the eruptive activity alternated between `wet' and `dry'. The pyroclastic density current was transitional in particle concentration between a dilute pyroclastic surge and a high particle concentration pyroclastic flow. Unidirectional bedforms in unit B suggest that the depositional boundary was commonly turbulent and in this respect did not resemble conventional pyroclastic flows. However, unit B is relatively thick and poorly sorted, and was deposited more than 19 km from source, implying that the current comprised a relatively high particle concentration and in this respect, did not resemble a typical pyroclastic surge. 相似文献
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60.
为分析谷胱甘肽硫-转移酶M基因(glutathione S-transferases M,GSTM)与鱼类低温耐受性的相关性,本实验运用PCR-SSCP技术研究了130尾斑马鱼(Danio rerio)GSTM基因5?UTR、3?UTR和第一内含子序列的单核苷酸多态性(Single nucleotide polymorphisms,SNPs),同时分析了筛选到的基因型与其低温耐受性状的关联性。结果显示,在其5UTR区域检测到AB、BC、AC 3种基因型个体,共A、B、C 3个等位基因,其观测杂合度和期望杂合度分别是1.000和0.570,多态信息含量为0.472,所检测群体在该座位偏离了Hardy-Weinberg平衡;第1内含子中检测到DD、DE和EE 3种基因型个体,共D、E两个等位基因,其观测杂合度和期望杂合度分别为0.408和0.477,多态信息含量为0.362,群体在该座位符合Hardy-Weinberg平衡。3'UTR区域中没有发现多态性。上述2个SNP座位与斑马鱼低温耐受性状的关联分析结果表明,5'UTR区3种基因型与低温耐受性状均没有显著相关性(χ2=4.029,P0.05)。而第1内含子3种基因型与低温耐受性状显著相关(χ2=8.498,P0.05):DD基因型在耐低温群体中占优势(50.00%),并表现为对受低温胁迫斑马鱼的保护性因素(OR=0.520,95%CI=0.255–1.061),而DE基因型在不耐低温群体中占优势(51.31%),表现为低温胁迫下斑马鱼的危险因素(OR=3.012,95%CI=1.413–6.419)。研究结果为GSTM基因SNPs位点与斑马鱼低温耐受性能关联分析提供了依据,也将为海水经济鱼类抗寒标记筛选育种提供参考。 相似文献