矿物材料学的内涵与特征

经过20余年的研究与发展,矿物材料学已经成为材料科学与工程中一个相对独立和完善的组成部分,由于其定义、内涵与特征等基本问题与材料科学的从属性和独特性,多年的研究认为:矿物材料学是研究矿物材料的组成与结构、制备与合成、性能和使用效能以及矿物原料性质与特点等五要素及其相互关系和规律的一门学科.这五要素是具有内部互相联系和作用的有机整体,研究这五要素并了解它们之间的相互关系和规律构成了矿物材料学的内涵.矿物原料性质与特点是其他四要素的基本前提或重要基础,矿物原料及其与其他四要素的关系以及矿物在其他四要素中的关键性都体现了矿物材料学的矿物科学属性,正是因为兼具材料科学属性和矿物科学属性的矿物材料学这一重要特征使其有别于其他学科,而具有了理论及实用价值.     

长江流域河水和悬浮物的锂同位素地球化学研究

深入理解流域侵蚀过程中的锂同位素分馏对于运用锂同位素来示踪化学循环和气候变化是十分必要的。研究集中在长江干流和主要支流的水体和悬浮物的锂及锂同位素组成。长江流域水体的锂及锂同位素组成（δ⁷Li）分别为150~4 570 nmol/L和+7.6‰~+28.1‰,两者沿上游至下游的变化趋势相反。悬浮物锂同位素组成（δ⁷Li）变化比较稳定,分别为41~92 μg/g和-4.7‰~+0.7‰,而且总是低于相应水体的锂同位素组成。悬浮物和流体之间的锂同位素分馏系数在0.977和0.992之间,与悬浮物的量及组成存在明显相关性,反映了粘土矿物的吸附和化学风化的程度。锂含量与锂同位素组成之间良好的负相关性表明流域水体的锂来自2个端元混合：其一可能是蒸发盐岩,并伴有深部热泉水;其二可能是硅酸岩。     

江苏危机矿山深部及外围潜力资源找矿

介绍了危机矿山的定义.对江苏省主要固体矿产矿山的危机程度进行了综合分析.叙述了能源矿产、金属矿产和其他非金属矿产等矿山所属的危机程度.指出了危机矿山存在的主要问题,即矿产资源保证程度低;资源潜力依据充分,但找矿难度大.就江苏危机矿山深部及外围潜力资源找矿工作,提出了一些建议.     

“标贯”确定粘性土承载力标准值简易计算法

标准贯人（“标贯”）试验锤击数,要确定粘性土地基承载力标准值简易计算公式。将经杆长修正的标准贯人击数N进行统计分析,再把修正击数平均值带人相关方程,计算粘性土的承载力标准值fk,从而简化了计算过程。     

超高压变质岩矿物中的显微构造缺陷:来自TEM和FTIR研究的证据

超高压变质矿物的某些显微构造缺陷可能指示了岩石短暂和快速抬升过程。文中报道了中国大别山双河地区超高压硬玉石英岩矿物显微构造缺陷的透射电镜(TEM)和Fourier变换红外光谱(FTIR)的研究结果。用TEM研究方法,在硬玉石英岩中硬玉包裹体内发现了亚微米级天然蒙钠长石(MA,C2/m)、高钠长石(HA,C)和低钠长石(LA,C)三种多形变体。表明岩石在折返过程经历过高温变质作用(>930℃),以及退变质过程的快速冷却;在石英包裹体内发现了纳米级柯石英和石盐子矿物,提供了柯石英转变为石英以及峰期变质条件下高盐流体存在的证据。"名义上无水矿物"(NAMs)的结构水(OH/H2O)是以缺陷形式赋存于矿物结构中。FTIR分析结果显示硬玉、石榴石、金红石和石英中结构水的平均含量分别为1000×10-6、(900~1600)×10-6、>2000×10-6和<4×10-6,硬玉石英岩全岩含水量为(490~600)×10-6,表明在高压-超高压变质作用过程中,地壳或原岩中的水可以通过这些NAMs携带到地球深部。该类显微构造缺陷可能是大陆碰撞造山带在高应变速率下的局部弱化和深部断层作用的结果。     

碎屑岩自生粘土矿物的沉淀作用及其对储层的影响——以川西坳陷上三叠统须家河组砂岩为例

粘土矿物是影响碎屑岩储层物性的重要因素.本文以川西坳陷孝泉-新场-合兴场地区上三叠统须家河组砂岩为例,应用铸体薄片、普通薄片、X射线衍射分析和扫描电镜分析,研究了在成岩过程中自生粘土矿物的沉淀作用及其对储层的影响.结果表明自生绿泥石对储层原生孔隙的保存和次生孔隙的发育有利,自生高岭石的含量反映了次生孔隙的发育程度,而伊利石对储层的影响是负面的.     

黔北后槽下石炭统含铝岩系的粘土矿物

为揭示黔北下石炭统含铝岩系的沉积环境,本文利用贵州遵义县后槽TC718剖面系统试样的粘土矿物进行x一射线衍射测试及特征分析。含铝岩系粘土岩与下伏桐梓组粘土页岩在矿物组合和成分上均有明显的差异,水云母的结晶度指数、开形指数在剖面纵向上有三个变化拐点：一是含铝岩系与下伏桐梓组粘土页岩分界处;二是含铝岩系上、下段的接触带;三是含铝岩系顶部含炭质粘土岩出现的临界面。其变化特征表明,本区下石炭统含铝岩系粘土岩段为海相或海陆过渡相,铝质岩段为残积一坡积相,顶部为大陆湖沼相;下奥陶统桐梓组页岩段为海相。     

西藏罗布莎蛇绿岩铬铁矿中的超高压矿物和新矿物(综述)

近十余年来的研究,在西藏雅鲁藏布江缝合带中的罗布莎蛇绿岩型铬铁矿中,发现可能来自深部(>300km深度)异常地幔矿物群.该矿物群中具有深部成因指示意义的矿物有:①呈斯石英假象的柯石英;②微粒金刚石和产在锇铱矿中的原位金刚石;③铬铁矿和饿铱矿巾发现硅尖晶石;④铬铁矿中发现硅金红石;⑤呈八面体假象的蛇纹石和绿泥石,并具有清晰的爆炸结构;⑥方铁矿和自然铁矿物组合.此外,罗布莎铬铁矿中有4个新矿物获批准,并在极地乌拉尔蛇绿岩铬铁矿中也发现了大最微粒金刚石和碳硅石等地幔超高压矿物.蛇绿岩铬铁矿中发现来自地幔深部的超高压矿物,提供了铬铁矿可能深部成因的重要信息,该发现有可能改变传统的蛇绿岩铬铁矿的形成于俯冲带上的浅部环境(<50 km深度)的认识以及蛇绿岩成因的概念.     

Provenance of late Palaeozoic metasediments of the Patagonian proto-Pacific margin (southernmost Chile and Argentina)

In this provenance study of late Palaeozoic metasediments of the Eastern Andean Metamorphic Complex (EAMC) along the south Patagonian proto-Pacific margin of Gondwana, the palaeogeological setting of the continental margin in Devonian–Carboniferous and Permian times is reconstructed. The study is based on detrital heavy mineral contents, chemical compositions of tourmaline grains, and whole rock element and Nd-Sr isotopic compositions. Element and isotopic compositions reveal that Devonian–Carboniferous metaturbidites deposited before the development of a Late Carboniferous–Permian magmatic arc along the margin were mainly fed from felsic, recycled, old continental rocks. The last recycling phase involved erosion of metasediments that were exposed in Patagonia. Feeder systems to the basin cut either through epidote-rich or garnet-rich metasediments. In Permian time, EAMC metaturbidites were deposited next to the evolving magmatic arc and were derived from felsic, crustal rocks. Two provenance domains are recognised. The metasediments of the northern one are chemically similar to those of the Devonian–Carboniferous metasediments. This domain was fed from the metasedimentary host rocks of the magmatic arc. The southern domain probably was fed from the arc proper, as indicated mainly by the dominance of metaplutonic lithic fragments, abundant detrital biotite, and the major element composition of the metasediments.     

Out-of-sequence thrusts and paleogeography of the Rhenodanubian Flysch Belt (Eastern Alps) revisited

The Oberstdorf nappe of the Western and the Laab nappe of the Eastern Rhenodanubian Flysch (ERF) were independently identified as out-of-sequence thrust units by facies studies (Mattern 1999) and zircon analyses (Trautwein et al. 2001a, b, c), respectively. A new look at both areas reveals mutual similarities and new evidence for the out-of-sequence concept. Paleocurrent and heavy mineral data make it possible to reconstruct the sediment influx directions. From the Barremian to the mid-Campanian, the western and eastern basin segments were fed with south-derived garnet and north-derived zircon/”ZTR” (i.e., zircon, tourmaline, and rutile). Because both out-of-sequence units are relatively rich in zircon/ZTR they must have occupied the northernmost basin position. In the Western Rhenodanubian Flysch segment, the Sigiswang nappe occupied the central and the Üntschen nappe the southernmost basin position. In the ERF segment the central basin is represented by the Greifenstein nappe and the southernmost basin by the Kahlenberg nappe. Both out-of-sequence units do not occur in the northernmost and tectonically lowest position in their respective nappe piles as they were thrust over the other nappes. The reconstructed basin positions of the thrust units are suggested by the observation of a gradient in heavy mineral content in the thrust units. This paleogeographic arrangement is least problematic and renders models with differently positioned thrust units, requiring debris-shedding intrabasinal ridges, as unnecessarily complicated. Instead, we suggest that gradual changes in heavy mineral composition existed in across-basin direction. Garnet may stem from the Central Gneiss Complex of the Tauern window and formerly exposed lateral equivalents, all representing the southern Mid-Penninic zone. We assign the Falknis/Tasna nappe and formerly exposed lateral equivalents to the northern Mid-Penninic zone which served as the zircon/ZTR source. Interpreting Ebbing’s (Ph.D. thesis, Freie Universität Berlin, pp 1-143, 2002; Fig. 6.10) density section, we suggest that Mid-Penninic crust exists beneath the Central Gneiss Complex. During the latest Cretaceous much garnet was also N-derived. This may reflect processes related to the consumption of the North Penninic basin.