Jurassic Period

Jurassic Period的基本解释

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侏罗纪

与Jurassic Period相关的网络例句 [注：此内容来源于网络，仅供参考]

During early middle Jurassic period, Quemocuo formation in NQB was offshore lake deposition with marine feature, in SQB was shelf deposition, which indicted that an intense rifting and sea level rising with more large range, and consequently, eroding area was shrunk and deposition area was expanded.4. According to the result of stratigraphic surface features, division and correlation, and the paleographic characteristic, Qiangtang Basin during late Triassic -early middle Jurassic period could be divided into two basin developing stages with difficult tectonic nature, remnent epicontinental basin stage in Carian -early Norian of late Triassic and rifting basin stage in middle Norian of late Triassic - early middle Jurassic period respectively.

雀莫错组在羌北盆地为近海湖泊沉积，更具海相色彩：南羌塘主要为外陆棚沉积，反映羌塘盆地再次发生较强烈的裂陷作用和较大幅度的海平面上升，形成陆源剥蚀区缩小，沉积覆盖面增大的古地理面貌。4、根据地层界面特征、地层划分与对比结果和岩相古地理演化特征可将晚三叠世—中侏罗世早期羌塘盆地划分为两个不同构造性质的盆地发展时期，分别为晚三叠世卡尼期—若利早期的残留内陆表海沉积盆地发展与消亡时期和晚三叠世若利期中晚期—中侏罗世早期的裂陷盆地的形成与发展时期。

This dissertation was focused on the research about the formation and evolution of NQB from the Late Triassic to the early middle Epoch of Jurassic Period, including integrated analyzing the characteristic of the key stratigraphic surfaces, the time of the key stratigraphy, regional rock straigraphy, biostratigraphy and chronostratigraphy, sedimentary system and depositional facies. On basis of these analysis, a tectonic evolution model have been established for NQB during from the Late Triassic to the early middle Epoch of Jurassic Period.1. After the systematic surface analysis about main stratigraphy units, we found that:(1) the bottom of Xiaochaka formation was comformity with the middle Triassic in the basin, and in the north margin it was deposited and overlapped on the different period stratigraphy before Triassic.(2) The top surface of Xiaochaka formation developed regionally karst and paleo-karst breccia, and was uncomformity with Nadigangri Formation, these things suggest that NQB in Xiaochaka depositing stage was developed from middle Triassic basin, and then an extensive regression occurred, the deposition was over and erosion come into being.(3) The lithologic assemblage, geochemistry, mixed fossils, and stratigraphy overlapping characteristic of Quemocuo Formation in early middle Jurassic indicted that the uncomformity surface was an extension-unconformity.2. Integrated analysis about stratigraphy division and correlation indicted that:(1) the paleontologic assemblage of Xiaochaka formation show its time was Carian -Norian stage of late Triassic. According to it was overlapped by late Triassic Nadigangri Formation, so Xiaochaka formation should be Carian - early Norian stage.(2) the SHRIMP Zircon U-Pb age of Nadigangri formation volcanic rocks wear vary form 216 to 205 Ma, so its time should be Norian, but maybe extended into Rhaetian Stage.(3) The age of its bottom volcanic rocks, the fossil assemblages of its middle and upper members and overlapped by lower Jurassic, indicted the age of Riganpeicuo Formation was Norian - Rhaetian stage. And the same time, the volcanic rocks geochemistry of Nadigangri and Riganpeicuo formation both reflected that they wear formed in rift tectonic settings. The lower lithologic and surface characteristic, fossil assemblages and its upper maybe was conformity with lower Jurassic, all reflected that the age of Tumengela Formation in Tumen area should be Norian - Rhaetian stage.

论文对晚三叠世—中侏罗世早期盆地的形成与演化开展了研究，包括关键地层界面特征分析、关键地层时代归属分析、区域岩石地层、生物地层和年代地层的综合对比分析、区域沉积体系与沉积相分析、岩相古地理分析，最终建立晚三叠世—中侏罗世早期羌塘盆沉积—构造动力演化模式。1、系统的对各地层单元的界面分析发现：(1)肖茶卡组底界在盆地内部与中三叠统整合关系，在盆地北缘为沉积超覆于不同时代的前三叠系之上：(2)肖茶卡组顶界面发育古岩溶角砾岩，与上覆那底岗日组为岩溶不整合接触，说明肖茶卡组沉积时期的羌塘盆地是在早中三叠世的盆地基础发展起来的，后期出现了广泛的海退事件，使盆地结束沉积并遭受风化剥蚀作用；(3)中侏罗统雀莫错组的岩性组合特征、岩石化学特征、古生物化石混积和地层的沉积超覆现象均表现出裂陷环境下形成的伸展不整合面的特征。2、综合地层划分与对比分析认为：(1)肖茶卡组古生物化石组合反映其时代为晚三叠世卡尼期—若利期，根据其上被上三叠统那底岗日组不整合覆盖，将其时代厘定为卡尼期—若利期早期；(2)那底岗日组火山岩SHRIMP锆石U-Pb年龄在216～205 Ma之间，其时代主要为若利期，可能包含有瑞替期：(3)日干配错组底部火山岩的年龄、中上部化石组合及其被下侏罗统整合覆盖，综合反映的时代为晚三叠世若利期—瑞替期，而且那底岗日组火山岩和日干配错组火山岩的地球化学成分分析反映两者均为引张构造背景下的产物；土门地区的土门各拉组的下部岩性及界面特征、化石组合和上部可能被下侏罗统整合覆盖，综合反映其时代为若利期—若利期。

The south-north united tectonic environment and tectonic pattern does not exist. The east-west trend thrusting Nappe structure of Majiatan and Hengshanpu can not represent the whole western margin of Ordos. The attempt to solve the regional tectonic problem with simple tectonic pattern is against the geological theory, especially in the Helan Mountain region.(2) After the geochemical data analysis of Ruqigou basalt in Helan Mountain, the article illustrates that it belongs to continental rift basalt which appeared in the late-Triassic and early middle Jurassic. Meanwhile the article states that the region is located in the rift environment of an extension background and Rudigou is located in the central part of the rift.(3) The article illustrates that the western ridge of Helan Mountain used to be on a slope and topography slowly declines from west to east after analysis and demonstrations of the distribution under XiaoSongshan bedding fault. Through comprehensive analysis of the no-strong deformation and bedding fault features, the article states that the Xiaosongshan bedding fault used to be gravity slip detachment structure and it represents the extension from the east to the west. Based on the above and analysis and demonstrations of isotope age and track datting, the article illustrates that the ? characteristic of the east of the western ridge of Helan mountain being higher than the west is the result of its late tectonic reverse.(4) Through comparison between Rujigou region Mesozoic Era late Triassic period-early and middle Jurassic period deposit and that of Ordos Basin and the analysis of the late Triassic period extension and early -middle Jurassic Period deposit povenevance it sets forth that during the period, Rujigou region was part of a large deposit basin which was closer to the northern povenevance and farther from the western povenevance.

以马家滩和横山堡为代表的东西向逆冲推覆构造模式，在整个鄂尔多斯盆地西缘不具有全区统一性，那种试图用单一的构造模式解决本区构造问题的尝试，无疑是与地质实际相悖的，尤其是对贺兰山地区；(2)通过对贺兰山汝箕沟玄武岩地质地球化学测试分析，提出其为大陆裂谷玄武岩，其形成时代为晚三叠—早中侏罗世，并通过该玄武岩的稀土和微量元素的测试分析资料进行了多种判别分析，最终确定该区处于拉张背景下的裂谷环境，汝箕沟地区大致处于当时裂谷的中心部位；(3)通过对小松山断层面之下地层分布规律，结合其变形特征的分析论证，认为当时贺兰山西麓处于一个由东向西平缓抬高的斜坡环境，并通过小松山断层面之下地层的非强烈变形及顺层断层特征等的综合分析，认为贺兰山西麓的小松山断层原本是一重力滑覆断层，它代表了近东西向的拉张，在此基础上通过裂变径迹测试资料的分析论证对其做了进一步认定，目前贺兰山西麓东高西低的剖面特征是该区后期构造反转的结果；(4)通过对汝箕沟地区中生代晚三叠世—早中侏罗世沉积与鄂尔多斯盆地内部的对比、晚三叠世延长组及早中侏罗世沉积物源和水流向分析，认为该时期汝箕沟地区为一更靠近北部物源，而距西部物源明显较远的沉积环境，是一更大型沉积盆地的一部分。

与Jurassic Period相关的网络解释 [注：此内容来源于网络，仅供参考]

Jurassic period：侏罗纪

侏罗纪(Jurassic Period)得名于法,瑞边境的侏罗山(现名汝拉山),开始于大约一亿九千万年. 当时的地球温暖潮湿,适宜动物生存,爬行动物在陆地和海洋继续发展并成功占据了天空. 直到侏罗纪晚期,翼龙类在天空才有了竞争者-鸟类,

Jurassic period：<地>侏罗纪

iso-return period 等重现周期 | Jurassic period 侏罗纪 | low-flow period 枯水期,低水期,枯季

Jurassic period：<地>侏罗纪

iso-return period 等重现周期 | Jurassic period <地>侏罗纪 | low-flow period 枯水期,低水期,枯季