查询词典 basaltic rocks

The activities of Wangtian′e volcano lasted for three periods:①The Changbai period volcanic rocks consisting mainly of trachybasalt with small amount of alkalic basalt and basaltic trachyandesite;② The Wangtian′e period can be further divided into early and late periods, the early period volcanic rocks consisting of basaltic trachyandesite and trachyte, the late period volcanic rocks cosisting of alkalic rhyolite;③The Hongtoushan period volcanic rocks consisting of alkalic rhyolite.

望天鹅火山活动从早到晚分为三期：①长白期以粗面玄武岩为主，少量碱性玄武岩和玄武质粗安岩；②望天鹅期又分早晚两个亚期，早期玄武质粗安岩和粗面岩，晚期碱性流纹岩；③红头山期碱性流纹岩。

The Middle Devonian Beitashan Formation consists of a series of intermediate-basic volcanic rocks intercalated with more than 100 m thick picritic layer at the bottom, whereas the Middle Devonian Yundukala Fm. is composed of a series of shallow-sea fine-clastic rocks interbedded intermediate rocks and intermediate-basic rocks. The Late Devonian Jiangzierkuduke Fm. includes pyroclastic rocks intercalated with intermediate-basic and intermediate-acid rocks, whereas the Late Carboniferous Batamayineishan Fm. consists chiefly of basalts and basaltic andesites intercalated with tuff, siltstone and carbonaceous shale.

其中中泥盆世北塔山组为一套中基性火山岩，并且底部含有厚度超过100m的苦橄岩；中泥盆世蕴都喀拉组为一套浅海相细碎屑沉积岩夹中性、中基性火山岩；晚泥盆世江孜尔库都克组为火山碎屑岩夹中基性和中酸性火山岩组合；而晚石炭世巴塔玛依内山组以玄武岩和玄武安山岩为主，夹凝灰岩、粉砂岩和炭质页岩。

According to the variation in the components of intermediateacid igneous rocks coming from the lower crust, it is possible to restrain the depth of the source area and the minimum thickness of the crust, and thus to provide important information for the study of the deep process of the continental intraplate mineralizationGlobally, many world level porphyry copper deposits and metallogenic systems formed by hypabyssal hot liquid have their close relationship with the synchronous adakite in spacetime and genesis; domestically, the adakitelike rocks have been identified to be related to the metallogenesis in the main metallogenic areas in ChinaThe recognition of adakitelike rocks having no relationship with the process of subduction makes it possible to construct a metallogenic model of continental intraplate porphyry metal deposits by combining other geological evidences, and this model is totally different from the metallogenic model of porphyry copper deposits with Bsubduction setting constructed by Sillitoe (1972)The existence of adakitelike rocks may be the necessary condition but not the sufficient one for forming the largescale porphyry deposits and the hypabyssal hotliquid deposits, whose metallogenic elements mainly came from the mantleThe metallogenic potential of adakitelike rocks is achieved by the entering of the mantle material, and the metallogenic specialization of adakitelike rocks is decided by the distribution characteristics of the metallogenic elements in the upper mantleAn important reason for the adakitelike magma related to subduction being advantageous to mineralization is that there were abundant high pressure and high temperature liquid coming from the subducted platepieces and the magma of high fO2 coming from the melting of subducted platepiecesHowever, for those adakitelike rocks, whose occurrence has continental plate background but does not relate to the subduction, their metallogenic mechanism is not clear yetBased on the concept of modern mineral exploration and combined with the analysis of integrated geological information, we may better realize the practical prospecting significance of the adakitelike rocks

根据起源于下地壳的中酸性岩浆岩的成分变化，可以约束其源区深度以及地壳最小厚度，为大陆板内成矿作用的深部过程研究提供重要信息。全球范围内，许多世界级斑岩铜矿和浅成热液矿化系统与同期的埃达克质岩存在密切的时空与成因联系，在国内主要成矿区带也识别出与金属成矿作用有关的埃达克岩。与俯冲过程无关的埃达克质岩的识别，使我们有可能结合其他地质证据构建完全不同于Sillitoe(1972)B型俯冲环境的斑岩铜矿成矿模式的大陆板内斑岩型金属矿床成矿模式。对于规模巨大、矿质主要源自地幔的热液矿床的形成，埃达克岩可能是必要条件，但不是充分条件。埃达克岩的成矿潜力通过地幔物质加入而获取，埃达克岩的成矿专属性由上地幔成矿元素分布特征决定。与俯冲有关的埃达克质岩浆之所以有利于成矿，重要的原因是存在大量来自俯冲板片的高压、高温流体以及俯冲板片熔融形成高氧逸度(fO2)的熔体，但产出在大陆板内背景、与俯冲无关的埃达克岩的成矿机制还不清楚。根据现代资源勘查理念，结合综合地质信息分析，埃达克质岩具有实际找矿意义。

The authors think that the magmas of the intermediate-acid volcanic rocks were derived from basaltic magmas of the lower crust and are mixed magmas produced by the increase of geothermal gradients due to diapiric injection of basaltic magmas and partial melting of intermediate-basic metamorphic igneous rocks in the lower crust,and that they resulted from a series of tectonomagmatic activities that took place when the closing of the Mongolian-Okhotsk sea trough and continent-continent collision caused crustal thickening and brought about the formation of the Hinggan-Mongolian orogenic belt in the process of oblique subduction of the Paleo-Pacific plate beneath the Siberian plate.

中文摘要：通过对大兴安岭北段晚侏罗世吉祥峰组中酸性火山岩的岩石地球化学研究，发现其中存在高Sr低Y型火山岩，即文献上所称的埃达克质岩，笔者认为中酸性火山岩的岩浆起源于下地壳玄武质岩浆，为玄武质岩浆底辟上侵引起地热梯度增加、下地壳中基性变质火成岩石部分熔融的之混合岩浆，是古太平洋板块向西伯利亚板块斜向俯冲过程中，蒙古鄂霍次克海槽封闭，陆壳碰撞使地壳加厚，形成兴蒙造山带时所引起的一系列构造岩浆活动。

According to the literatures about the gold contents in crust, rocks and sediments published in recent 15 years and a huge amount of reliable analytical data in the study about crust and rocks accumulated, it is recommended that the gold abundance in the crust and in the exposed crust are 1.0 and 0.8 ng/g, the average contents of gold in rocks, igneous rocks, sedimentary rocks and metamorphic rocks are 0.9, 0.6, 1.0 and 1.0 ng/g, the average contents of gold in stream sediments, flood plain sediments, shallow sea sediments and soils in China are 1.4, 1.6, 1.2 and 2.0 ng/g, respectively.

根据近15年来发表的大量有关金在地壳、岩石和沉积物中含量的文献，结合作者在地壳与岩石研究中积累的金的大量可靠数据，综合给出金的地壳丰度为1.0ng/g，出露地壳丰度为0.8ng/g，金在岩石、火成岩、沉积岩和变质岩中的平均含量分别为0.9、0.6、1.0和1.0ng/g，金在中国水系沉积物、泛滥平原沉积物、浅海沉积物和土壤中的平均含量分别为1.4、1.6、1.2和2.0ng/g。

The Mesozoic volcanic rocks are mainly located in Huoshiling Formation and Yingcheng Formation. The former consists of basaltic andesite, trachyandesite and dacite, the latter is composed of basaltic trachyandesite, trachyandesite and rhyolite. The cathodoluminesence images and high Th/U ratios of the zircons suggest their magmatic origin.

松辽盆地南部中生代含火山岩地层主要包括火石岭组和营城组，其中火石岭组火山岩由玄武安山岩－粗安岩－粗面英安岩组成，营城组火山岩由玄武质粗面安山岩－粗面安山岩－流纹岩组成。

Among other things, paleovolcanic rocks at Shizuitang may be subdivided into olivine phenocryst-bearing basaltic komatiite and clinopyroxene phenocryst-bearing basaltic komatiite.

其中石咀塘古火山岩可进一步分为含橄榄石斑晶玄武质科马提岩和含单斜辉石斑晶玄武质科马提岩2种类型。

In contrast, the depth of mineral crystallization in the shallow part, which represents the condition of basaltic magma chamber, is in the range of 37~41 km, indicating that the basaltic magma might have been an mineral chemistry of the clinopyroxenes shows that the volcanic rocks in this area belong to subalkaline series and were probably formed in and island arc setting.

基于单斜辉石的成分和演化，确定了该地区火山岩属亚碱性系列，其构造背景为岛弧环境。

The SiO2 content of the dike swarms varies from 50.22% to 61.10% and they are basic-intermediate rock series, mainly basic. The Al2O3 content is generally higher than 15% and they are high aluminum basaltic rocks. The lower magnesium index (Mg#=42.77~62.28) and TiO2 content (0.97~2.41%) illuminate that they suffered magnesium-iron minerals' fractional crystallization and that they did not crystallize from original basaltic magma. The values of Na2O/K2O are all above 1, indicating lower K character. Chemically discriminated, these dike swarms are sub-alkaline rock series.

岩墙群的SiO2含量为50.22~61.10%，属于基性和中基性岩类，以基性为主；它们的A12O3含量普遍高于15%，属高铝玄武岩类；具有较低的镁指数（Mg#=42.77~62.28）及TiO2含量（0.97~2.41%），说明它们经历了镁铁质矿物的结晶分异作用，也指示它们不是由原始玄武岩浆结晶；Na2O/K2O都大于1，显示出低钾的特点；岩石化学判别，岩墙群岩石属亚碱性系列。

With regard to the basaltic lavas, the felsic rocks resulted from partial melting of continental crust, which closely related to basaltic underplating.

古亚洲洋俯冲板块对古老岩石圈的交代作用在岩石圈减薄和置换过程中起了很重要的作用。

The United Kingdom has pledged to provide technical assistance to the peacekeeping effort in Darfur, including airlifting supplies and equipment to assist the African peacekeepers.

英国承诺为达佛的維和努力提供技术帮助，包括提供非洲的維和部队空运补給和裝备。

Results: The level of ET-1mRNA in placental villus was significantly higher in pre-eclamptic women than that in control group.

结果：妊高征组患者胎盘绒毛组织ET-1 mRNA的表达较正常妊娠组明显增高。