The Inclusions in Superdeep Diamonds: Indication and Response to Deep Mantle Physical and Chemical Environment

Superdeep diamonds and their inclusions are important samples to probe the physical and chemical environment and constitution of Earth’s deep mantle. By combining the studies of high-precision in-situ analysis and HPHT synthetic diamond experiments, and by reviewing the new discovery of classical mineral inclusions and their combinations, the ranges of different inclusion combinations, as well as the relationship between trace elements and temperature-pressure conditions were reoriented. The so-called nominally anhydrous minerals combinations, metal phases and redox environments in superdeep mantle were also affirmed. Meanwhile,the recent findings of inclusions and isotopes in superdeep diamonds support the fact that the remaining subduction ocean crust may be a significant reservoir of the deep mantle’s water and the deep mantle carbon cycle is closely related to oceanic subduction. Furthermore, although Chinese scholars have discovered some kinds of superdeep inclusions in diamonds from North China Craton and Yangtze Craton, and made considerable progress in the study of the formation of UHP diamonds and the genesis of ophiolite diamonds, there are still many scientific questions about superdeep diamonds that require further research.     

轮古西奥陶系潜山洞穴型岩溶储层发育特征与充填规律

洞穴型岩溶储层是塔里木盆地轮古油田缝洞型碳酸盐岩油藏的主要储集空间类型,多数高效井均钻遇大型洞穴型岩溶储层。依据轮古西奥陶系潜山大量单井资料分析,洞穴型岩溶储层可分为充填洞穴、半充填洞穴和未充填洞穴三种类型。结合古地貌精细刻画与岩溶垂向分带成果,认为古地貌位置由岩溶台地向岩溶缓坡和岩溶盆地逐渐降低,而洞穴发育和充填程度在逐渐增高。未充填与半充填洞穴主要发育在岩溶台地和岩溶缓坡的溶峰边坡、溶丘边坡及沟槽谷洼地边坡等地貌单元。表层岩溶带、径流溶蚀带洞穴型岩溶储层发育频率最高,其次为垂直渗滤带和潜流溶蚀带。未充填与半充填洞穴型岩溶储层主要发育在表层岩溶带。     

地质雷达在公路路面检测中的应用

探讨了地质雷达在公路路面无损检测中的应用,重点介绍了野外资料采集时的参数设置和室内数据处理,以及处理后资料的解释,并给出了应用实例。     

多伦地区晚侏罗世火山活动节律研究

多伦地区的晚侏罗世火山岩地层,可划分为满克头鄂博、玛尼吐、白音高老三个火山活动小旋回,通过对其岩石组成、岩相、结构构造及其变化的研究,从地球历史演化的阶段性、周期性和不可逆性的角度,探讨了该区晚侏罗世火山活动节律特征,进而从时空尺度对火山活动节律的级别和特征进行了划分和厘定,并探讨了不同级别节律的成因。     

四川冕宁冶勒变质火山沉积岩系中微古植物的发现及意义

位于扬子地台西缘康滇地轴中段的冶勒变质杂岩体中分布的变质火山沉积岩系,首次发现微古植物化石,计有１１个属３６个种,时代确定为中新元古代蓟县系—青白口系,为岩系的划分及归属提供了依据,证实有褶皱基底的存在。     

京源口隧道开挖对赖邦村水源的影响

通过对赖邦村取水区、京源口隧道区的水文地质与工程地质条件,以及断水时间与隧道开挖的对应部位的调查,得到的结论是隧洞开挖揭穿了赖邦村取水区的主要补给源--构造裂隙含水系统,使其改变了原有的排泄条件,导致地下水向隧道集中渗漏,是造成取水区水量不断减少的主要原因.     

The investigation of ultra-long-distance concrete pipe stuck in quartz sandstone formation using numerical simulation

During mountainous area construction by long-distance pipe jacking, the pipe stuck encountered. To reveal the cause of the pipe stuck, this paper investigates the pipe surface frictional resistance corresponding to different burial depths and surrounding rock parameters by ADINA finite element analysis. Parameter sensitivity analysis results show that the cohesion effect on the frictional resistance was small, the frictional resistance tended to decrease markedly with the increasing other rock mechanical parameters and the decreasing burial depth and friction coefficient of the pipes. After continuing to consider the prerequisite of simultaneously changing the elastic modulus, internal friction angle and burial depth conditions, a solution of the maximum number of pipes driven by a single intermediate jacking station (IJS) was reduced from 59 to 40 was proposed based on an integration of simulations with the field monitoring results. Finally, the pipe jacking project was successfully completed after adopting the improvement proposals.     

藏北蛇绿岩中尖晶石类矿物的化学成分

本文根据东巧蛇绿岩中镁铁质-超镁铁质杂岩的尖晶石化学成分特征,讨论了该区变质橄榄岩产生的构造位置、上地幔部分熔融程度等。东巧蛇绿岩组合代表一种过渡型岩石圈物质,这已为岩石学和地球化学的研究所支持。本文从矿物学方面又提供了新的论据。     

Tourmaline geochemistry and boron isotopic variations as a guide to fluid evolution in the Qiman Tagh W-Sn belt,East Kunlun,China

The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report chemical and boron isotopic compositions of tourmaline from wall rocks, monzogranites, and quartz veins within the belt, for studying the evolution of ore-forming fluids. Tourmaline crystals hosted in the monzogranite and wall rocks belong to the alkali group, while those hosted in quartz veins belong to both the alkali and X-site vacancy groups. Tourmaline in the walk rocks lies within the schorl-dravite series and becomes increasingly schorlitic in the monzogranite and quartz veins. Detrital tourmaline in the wall rocks is commonly both optically and chemically zoned,with cores being enriched in Mg compared with the rims. In the Al-Fe-Mg and Ca-Fe-Mg diagrams,tourmaline from the wall rocks plots in the fields of Al-saturated and Ca-poor metapelite, and extends into the field of Li-poor granites, while those from the monzogranite and quartz veins lie within the field of Li-poor granites. Compositional substitution is best represented by the MgFe_(-1), Al(NaR)_(-1), and AlO(Fe(OH))_(-1) exchange vectors. A wider range of δ~(11)B values from -11.1‰ to -7.1‰ is observed in the wall-rock tourmaline crystals, the B isotopic values combining with elemental diagrams indicate a source of metasediments without marine evaporates for the wall rocks in the Qiman Tagh belt. The δ~(11)B values of monzogranite-hosted tourmaline range from -10.7‰ and-9.2‰, corresponding to the continental crust sediments, and indicate a possible connection between the wall rocks and the monzogranite. The overlap in δ~(11)B values between wall rocks and monzogranite implies that a transfer of δ~(11)B values by anataxis with little isotopic fractionation between tourmaline and melts. Tourmaline crystals from quartz veins have δ~(11)B values between -11.0‰ and-9.6‰, combining with the elemental diagrams and geological features, thus indicating a common granite-derived source for the quartz veins and little B isotopic fractionation occurred. Tourmalinite in the wall rocks was formed by metasomatism by a granite-derived hydrothermal fluid, as confirmed by the compositional and geological features.Therefore, we propose a single B-rich sedimentary source in the Qiman Tagh belt, and little boron isotopic fractionation occurred during systematic fluid evolution from the wall rocks, through monzogranite, to quartz veins and tourmalinite.     

中昆仑造山带钾玄岩质火山岩的地质、地球化学和时代

 本文论述了中昆仑(北坡)4个地区第四纪火山岩的地质产状、岩石学、地球化学特征及时代。这一套岩石以安粗岩类为主,普遍含有普通辉石和斜长石斑晶,少数还有橄榄石、紫苏辉石或石英、透长石、黑云母斑晶。在化学上以富碱尤其富钾为突出特点,K₂O/Na₂O≥1,而且 Rb、Sr、Ba 等低场强元素和 LREE 也强烈富集,构成一个连续的钾玄岩系列(Shoshoaite Serics)。区域构造,地球化学和深源捕虏体的证据表明,本区钾玄质岩浆来自于上地幔的低度部分熔融,并受到地壳的同化和污染。火山活动大致从晚第三纪开始一直延续到第四纪,特别是中、晚更新世最为剧烈,是昆仑山及青藏高原快速隆升的新构造运动表现形式之一。