查询词典 Precambrian

These cycles plus two first-order cycles in the Phanerozoic successions have disclosed that a genetic link may be postulated for individual Earth shells and galactic precessional cycles.The stratigraphic records of the above-mentioned cycles are significant especially for the division of the Precambrian strata with lower stratigraphic resolutions.

尽管对地层记录中隶属不同级别沉积层序的间断面所代表的间断时限的绝对年限还难以精确估价，而建立在岩相及相序基础之上的旋回性地层记录的研究，是从复杂而不完整的地层记录中寻找出更多规律性的有效途径，特别是对生物地层分辨率不高的前寒武纪地层，尤其显得更加重要。

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。

Fail to execute a hard right turn immediately, and you smash into a face of Precambrian rock.

不要立刻执行一个坚硬正确的轮，和您抽杀入全寒武纪的岩石的面孔。

Northern Guangxi is an ideal region not only for research of Precambrian stratigraphy but also for ...

桂北是华南前寒武纪地层研究的理想地区之一，同时也是研究华南地壳演化和前寒武纪大地构造性质的最佳地区之一。

The major rock unit that forms the syncline is a red to maroon Precambrian quartzite.

The主要岩石单元，形成了向斜是红色，栗色的前寒武纪基底中寒武世地层包括quartzite。

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。

These dyke swarms are undeformed and unmetamophosed with beautifull flow structure to show the characteristics of Precambrian magma activity, which is rare in the world.

这些岩墙群未变形和未变质，保存了清晰完好的流动构造，完整地反映了前寒武纪岩浆活动的特征和流动构造，这在世界上是罕见的。

Some other older zircons with 206Pb/238U ages of 932 to 2443Ma were brought from Precambrian basement rocks at depth by strong submarine volcanic eruption and then deposited in quartz albitite together with hydrothermal fluids.

其他较老年龄锆石是由强烈的海底火山喷发作用从深部基底物质中带出的，并与热水流体一起沉积下来，赋存在石英钠长石岩中。

Molar tooth structures are episodically located in Precambrian subtidal shallow marine environment, and their temporal and spatial characteristics indicate incompatibility with stromatolites.

臼齿构造多产出于正常浅海潮下环境，并且呈幕式特点产出于前寒武纪地层记录中，其时空发育特点似乎表明与叠层石发育的不相容性。

The fault that appears to have broken in the earthquake is at or very near the boundary between the Precambrian rocks of the Pengguan Massif and the Mesozoic foredeep sediments of the Sichuan Basin .

在地震中被断裂层位于或者接近于彭观山丘前寒武纪岩石与四川盆地中生代前缘沉淀层的边界地带。该断裂带大多情况下向右横向

Warden: That's a beautiful dog, but don't bring her again.

那是条漂亮的狗，但是不要再把她带来了。

You get up in the morning – no hangover!

你第二天早上起来的时候—不会宿醉！