查询词典 Early Precambrian

Based on major and trace elements and isotope geochemical data, it is inferred that Sandouding suite is formed by magma melting of Late Archeozoic continent tholeiite source, and its geochemical variation is controlled by hornblende fractional crystallization. Besides fractional crystallization, the geochemical variation of Huanglingmiao suite is related to the mixing between dacitic magma and felsic magma. Dalaoling suite is probably derived from early Precambrian volcanics.

根据岩石化学和同位素组成推断，三斗坪岩套的源岩主要是晚太古代大陆拉斑玄武岩，母岩浆相当于英安质，岩套内的成分变化主要受角闪石分离结晶作用控制；黄陵庙岩套除受分离结晶作用影响外，成分变化主要与英安质母岩浆和某种长英质岩浆的混合有关；大老岭岩套的源岩亦为早前寒武纪火山岩。

The term ' Precambrian ' is now used mainly descriptively, and has been largely discarded as a geological term in the light of greater knowledge of the early evolution of life.

这个词现在主要用于描述性的，根据对早期生命进化的越来越多地了解，它作为地质学术语已经被丢弃。

Early Precambrian metamorphic complex, composed of khondalite series, BiHb gneiss series, granulite series and metamorphosed plutonic intrusions inside the supracrustal rocks, are well developed in Daqingshan area.

内蒙古大青山地区普遍发育由孔兹岩系、黑云角闪片麻岩系、麻粒岩系和侵位其中的变质深成岩构成的高级变质杂岩。

Four stages of granitoid plutonism took place in Precambrian, early Paleozoic （∈-D3）, late Paleozoic-early Mesozoic （D3-T3）, and late Mesozoic-Cenozoic, respectively.

该带内的花岗岩形成可以划分为4个时段，分别与4个造山旋回相对应：前寒武纪；早古生代；晚古生代—早中生代；晚中生代—新生代。

Of the five stages deformation, the exact ages of the (2) and (3) were determined by 40Ar/39Ar method as 290 and 259 Ma respectively.2. New results on the metamorphic belts and associated metamorphism of the Xiaopu metamorphic rocksBased on detailed microtextural observations and occurrence of typical metamorphic minerals, five metamorphic belts in the Xiaopu metamorphic rocks are identified. From the north to the south, they are biotite belt, garnet belt, staurolite belt, andalusite belt, and sillimanite belt. I suggested that the metamorphic belts occurred in the Xiaopu area belongs to the high temperature/low pressure series, may have resulted from the later Permian crust extension at ca. 290 Ma.3. I suggest that there may have been a Carboniferous backarc basin along the southern slope of the Harlik Mountain.Detrital Zircon SHRIMP U-Pb dating indicated that the sedimentary age of the Julideneng formation lithic sandstone must be later than late Devonian, most likely is Carboniferous rather than previously thought Precambrian. Analyses on its geologic setting, location of provenance, and sedimentary environment suggest the Carboniferous strata may form in a lagged backarc basin bounded by backarc uplifts.5. Reconstruction of the post-Paleozoic tectonic evolution history of the Harlik MountainThe tectonic evolution of Harlik mountains since the Paleozoic were reconstructed as followings:(1) arc-affinity magmative activities occurred during the middle-Ordovician to early-Silurian;(2) the middle-Silurian to late-Devonian was a back-arc uplift stage;(3) back-arc extension featured the Carboniferous period;(4) post-collisional extension and/then compression during Permian;(5) at the Mesozoic, differential uplift developed; and (6) the late Cenozoic is the intra-continental re-orogen stage.6. Primary estimation of the crust shortening is madeThe folded pre-Mesozoic strata were used to estimate crust shortening along the Harliknanshankou-Koumenzi, Shichengzi-Baishitou, and Qincheng-Xiaopu sections. Their shortening ratios are 16.2%, 19.8%, and 20.1% respectively corresponding crust shortening are 4.3, 9, and 11.3 km.

根据Ar-Ar热年代学研究，精确测定了早二叠世伸展变形和晚二叠世挤压变形的峰期时代分别为290Ma和259Ma.2、提出了关于哈尔里克山南麓小铺一带变质带和变质作用的新认识根据显微观察资料和特征变质矿物的出现，把小铺一带的变质岩由SW向NE方向依次划分为黑云母带、石榴石带、十字石带、红柱石带和矽线石带等变质带；初步确定该区的变质作用属于中温-低压型，变质作用发生的时代为290Ma左右，是该区早二叠世地壳伸展的产物。3、首次提出哈尔里克山南麓在石炭纪可能发育弧后盆地的新观点根据哈尔里克山南麓原"居里得能组"岩屑砂岩的碎屑锆石SHRIMP U-Pb定年，确认这套地层的沉积不早于晚泥盆世，很可能是石炭纪，而不是前人所说的前寒武纪；结合对其区域地质背景、源区位置和沉积环境分析，推测该区石炭纪可能为滞后弧后盆地和弧后隆起区构造背景。4、进一步证明哈尔里克山不发育与岛弧演化相关的泥盆纪岩浆活动根据对代表性闪长岩和花岗岩的锆石SHRIMP年代学研究获得的新资料，结合该区已有相关资料的综合研究，确定哈尔里克山岩浆岩分别形成于奥陶纪-志留纪和石炭纪晚期-二叠纪，不存在泥盆纪的岩浆岩，进而认为该区泥盆纪不属于岛弧环境。5、重建了哈尔里克山古生代以来的地质演化过程根据区域资料以及本次研究所获得的资料，把哈尔里克山古生代以来的构造演化划分中奥陶世-早志留世为岛弧、中志留世-晚泥盆世为弧后区、石炭纪弧后伸展、二叠纪为后碰撞伸展与挤压、中生代差异隆升和晚新生代陆内再造山过程等构造阶段。6、初步估算了哈尔里克山地壳缩短率和缩短量根据前中生代地层褶皱估算的哈尔里克山南山口-口门子、石城子-白石头和沁城-小铺三条剖面的地壳缩短率分别为16.2%、19.8%和20.1%，相应的地壳缩短量分别为4.3km、9km和11.3km。

As pyrites from Archean black shales worldwide show similar Fe iso- tope features to those from the two Chinese sulfide deposits, the enrichment of light Fe isotopes in early Precambrian ocean is likely to be regional, or even global.

导致早前寒武纪海洋富集Fe轻同位素的原因是海水中大量的Fe被氧化形成了富集Fe重同位素的磁铁矿和赤铁矿。

The high-grade metamorphic terrain of Hengshan located at the hinderland of North China Carton in northern part of Shanxi province, China, is a middle-lower crustal transition area of the typical continental crustal profiles of the Wutaishan—Hengshan—Datong—Jining of the early Precambrian etamorphic terrain in China.The Hengshan gneisses of the amphibolite—granulite facieses metamorphic terrain consist of the TTG gneisses and the horizontal adding mantle materials. The Supracrustal rocks in this area are composed of the mafic volcanic rocks and sedimentary rocks. The plenty of granitoid magma activities are the result of anatexes.

中文题名恒山中深变质岩区构造样式副题名外文题名 Tectonic styles of the high-grade metamorphic terrain of Hengshan 论文作者苗培森导师宋鸿林教授学科专业构造地质学研究领域\研究方向学位级别博士学位授予单位中国地质大学学位授予日期2001 论文页码总数88页关键词中深变质岩区构造地质恒山区域构造地质馆藏号BSLW /2003 /P548 /4 位于华北克拉通近中部的恒山中深变质岩区，亦即恒山高级变质岩区，是从五台山—恒山—大同—内蒙集宁这一浅变质岩区至中深变质岩区的我国早前寒武纪典型大陆地壳剖面代表中下地壳过渡带的地区。

We consider this transition belt being related to early precambrian basement structure and an important tectonic boundary inside the North China Craton.

本文分析认为，该坡折带代表早前寒武纪基底构造，是华北克拉通内部的重要构造边界。

This view has great significance for the study of the formation and evolution of the early Precambrian crust in western Shandong.

这一认识对探讨鲁西早前寒武纪地壳的形成和演化特征具有重要意义。

The paper presents the distribution and geologic characteristic of early Precambrian migmatitic granite and granite in Liaoning province.

研究了早前寒武纪辽宁省混合花岗岩和花岗岩的分布及岩石特征。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。