攀西地区铁钛氧化物矿物的显微结构

本文用矿石显微镜及单晶X射线分析方法,研究了攀枝花—西昌地区铁钛氧化物矿物的显微结构共生组合特点、各出溶相间的关系和分布方位以及不同岩石和矿石显微结构共生组合上的差异。业已查明它们受岩浆旋回和岩石类型所控制。本文指出了磁铁矿-钛铁晶石固溶体显微出溶结构可能是拐点分解经调制结构后的终期产物。     

海南戈枕韧性剪切带微观构造研究

韧性剪切带的定性－定量分析。能更清晰、直接地揭示构造运动生发发展过程应力、应变的状况。作者对海南戈枕韧性剪切带从显微构造角度作了系统研究工作。通过矿物粒度、形态比统计，在纵横方向上更明确了内部的复杂分带性；通过显微批向构造、矿物组权及变形变晶分析了探讨了构造活动的方式、方向；通过古应力值、剪应变、总位移量、弗林系数的测算，定量表述了该带变形机制及应力、应变速率大小。     

Rock-magnetic proxies of climate change in the loess-palaeosol sequences of the western Loess Plateau of China

Results of the first detailed study of the climate proxy record in the loess-palaeosol sequence at Xining-one of the few palaeoclimate sites in the currently arid western Loess Plateau of China-illustrate the importance of making many types of rock-magnetic measurements other than susceptibility. A multiparameter approach yielded confirmation that here, as elsewhere in the Loess Plateau, the susceptibility enhancement in palaeosols was caused primarily by ultrafine magnetite and maghaemite. Nevertheless, magnetic enhancement was caused not exclusively by changes in relative grain size, but also by variations in concentration and mineralogy of the magnetic fraction.
The effects of concentration variations were removed through normalization of susceptibility and anhysteretic remanence with saturation magnetization and saturation remanence, respectively. the resulting signal was ascribed more confidently to variation in magnetic grain size, which in turn was interpreted as a better proxy of pedogenesis than simple susceptibility. Variations in magnetic mineralogy were also determined to constrain interpretations further. the data were then used to discuss climate history at Xining. Finally, results from Xining were compared with other western sites and contrasted with eastern sites.
In summary: (1) data is presented from a new Loess Plateau site which also appears to yield a global climate signal; (2) a demonstration is made of a more rock-magnetically robust way to separate concentration, composition and grain-size controls on susceptibility and other magnetic parameters; and (3) models are provided for inter-regional comparisons of palaeoclimate proxy records.     

过去2．5百万年间黄土与深海古气候变化周期的对比分析

过去２．５Ｍａ间宝鸡黄土粒度记录和深海氧同位素曲线的Ｆｏｕｒｉｅｒ功率谱分析结果表明：在１．６Ｍａ以上部分，两者的周期性相当一致；但在２．５-１．６Ｍａ时段，两者的周期记录差异很大．深海氧同位素曲线记录的全球大陆冰量变化周期以与地轴倾斜度有关的０．０４１Ｍａ为主，而黄土粒度曲线记录的内陆风力强度变化周期则以与偏心率有关的０．４Ｍａ和０．１Ｍａ为主．造成这种异同的原因是：在２．５-１．６Ｍａ时段，内陆风力强度变化主要受地球轨道变化驱动，而从１．６Ｍａ前开始，转而主要受全球大陆冰量变化驱动．     

SOIL SHEAR STRENGTH: AN INDICATOR FOR ERODIBILITY OF THE LOESS SOILS

ＳＯＩＬＳＨＥＡＲＳＴＲＥＮＧＴＨ：ＡＮＩＮＤＩＣＡＴＯＲＦＯＲＥＲＯＤＩＢＩＬＩＴＹＯＦＴＨＥＬＯＥＳＳＳＯＩＬＳＷＡＮＧＧｕｉｐｉｎｇ；ＷＥＩＺｈｏｎｇｐｉｎｇａｎｄＺＨＡＮＧＺｈｉｇｕｏＡｂｓｔｒａｃｔ：ＦｉｅｌｄｅｘｐｅｒｉｍｅｎｔＳｕｎｄｅ...     

山东埠后古火山机构显微构造研究

埠后古火山机构由早白垩世陆相火山岩和次火山岩组成,铅、锌、铜、硫矿与后者有关。为了圈定火山通道的大致位置,在熔岩中采制定向切片,进行显微构造分析。通过变形、压密、阻挡、涡流等显微构造标志确定流动方位;利用长条状晶体的长轴方向确定流动线理。根据流动方位和流动线理圈出古火山口位置,进而指出在环火山颈的大断裂一侧,可能具区域找矿前景。     

安太堡露天煤矿排土场基底黄土的微结构演化与弱层的形成机理

本文根据安太堡露天煤矿排土场基底黄土的粘土矿物组成的微结构及其在分级荷载下微结构变化的研究，论述了排土场基底黄土内弱层的形成机理，提出弱层是在上覆排土压力下由于黄土的微结构变化而形成的演化弱层。并指出弱层的形成是导致排土场失稳滑坡的主要控制因素，这种弱层在新排土场设计时期并不存在，极具隐蔽性，但在设计时必须考虑在排土增至一定高度后，弱层的形成对排土场稳定性的影响，否则必将会存在重大滑坡隐患。     

豫西东部黄土工程特性研究

豫西东部堆积了第四纪不同时期的风成黄土及冲积、冲洪积黄土状土,全新统黄土、上更新统黄土具有湿陷性,为弱—中等湿陷。中更新统黄土一般不具有湿陷性。黄土的微观结构与土的形成时代、成因类型关系密切,全新统黄土颗粒间为开放或次开放式架空结构,具有较高的湿陷性,上更新统黄土接近接触式胶结,存在粒间架空孔隙,潜在弱—中等湿陷性;中更新统黄土为不等粒基底胶结结构,存在骨架接触式孔隙,一般不具有湿陷性;同时,黄土的渗透性又具有各向异性。     

山东长岛黄土沉积物的磁性与碳酸盐特征及其环境意义初探

通过对长岛沉积物采样和磁性测试,分析和讨论了长岛黄土沉积物的磁性特征:该剖面磁性矿物的含量并不是很高,且以亚铁磁性矿物为主,磁性矿物的粒度主要以细粒为主,亚铁磁性矿物的变化在沉积物磁性变化中占主导地位.通过对沉积物磁性特征和碳酸盐特征的对比发现:该剖面沉积物磁化率和碳酸盐具有很好的对应关系,并且明显表现出4个阶段的主要变化,对应了暖湿和冷干的气候旋回.根据沉积物的磁化率与古气候环境的内在联系,结合碳酸盐含量变化情况,对该地区风成沉积物的物源变迁及环境演变也进行了初步探讨和分析.