年代学

The techyte, formed during the time of ES3 (38.0~43.0 Ma) and with better stored property for oil and gas, has the characters of high alkalies (K2O+Na2O=10.22%~12.47%), high potassium (K2O/Na2O=0.69~1.88), high aluminium (Al2O3=17.82%~19.44%) and low titanium (TiO2=0.19%~0.67%), and belongs to the typical shoshonite series.

粗面岩的K-Ar年代学和地球化学表明，它们形成于沙三时期(38.0~43.0Ma)，具有富碱(K2O+Na2O=10.22%~12.47%)、富钾(K2O/Na2O=0.69~1.88)、高铝(Al2O3=17.82%~19.44%)、低钛(TiO2=0.19%~0.67%)的特点，属于典型的钾玄岩系。

For the Sibao group is got here by Sm-Nd isochron method dating the mafic-ultramafic whole rocks.

用Sm-Nd同位素年代学方法测得四堡群成岩时代为2412Ma。

In this his dissertation, the field geological work and modern analysis were finished on the Qulong ore-bearing porphyries. The mineralization chronology, petrology, element and isotopic geochemistry were studied on the porphyries. This dissertation also compare this work in Qulong ore-bearing porphyries with other ore-bearing porphyries in Gangdese belt, in order to probe into dynamical background and mineralization features of the ore belts in the condition of India-Eurasia collision.

在充分搜集、利用前人资料及成果的基础上，本论文力求以地球动力学和现代成矿理论为指导，采用先进的分析测试手段和野外地质工作相结合的方法，通过重点研究驱龙斑岩铜矿床的岩石学、同位素地球化学、常量与微量元素地球化学及成矿年代学，并与冈底斯其它斑岩矿床对比，探讨在印度—欧亚大陆碰撞条件下，冈底斯斑岩铜矿带的大陆动力学背景及成矿规律。

The 40Ar/39Ar isotopic dating of amphiboles collected from different depths of core samples in No. 3 intrusion gave a (228.2±3.0) Ma plateau age and a (230.1±7.1) Ma isochron age.

本次工作对采自不同深度岩心样品中的单矿物角闪石进行40Ar/39Ar同位素年代学研究，得到(228.2±3.0)Ma的坪年龄和(230.1±7.1)Ma的等时线年龄。

This paper demonstrates that the shading image of caliche lamination can be obtained by using an ordinary scanner, and then the characteristic curve of the image can be automatically est

初步研究表明，这种方法是可行的，它不仅提高了定年的精度和时间跨度，同时也拓宽了沉积物年代学方法在古环境及古气候研究中的应用

Short-lived radionuclides and long-lived isotope systems are normally used to date chondrites; the former systems can provide only relative ages while the later can provide absolute formation ages of chondrules, in contrast.

陨石年代学研究中常用定年工具包括短半衰期和长半衰期放射性同位素体系，其中前者可以给出陨石形成的相对年龄，而后者则可以给出绝对形成年龄。

These data provide new information to better understand the thermotectonic event of ca. 1800 Ma and the Precambrian crustal evolution of the North China Craton.

这为深人理解华北陆块1800Ma左右的热构造事件和华北早前寒武纪构造演化提供新的年代学资料。

A single zircon U-Pb age of 3605±43 Ma from the oldest granite-gneiss was reported in Aketashtage, eastern Altyn Tagh, which is located on the southeastern margin of the Tarim Platform.

在阿尔金山阿克塔什塔格曾测得3605±43 Ma的单颗粒锆石U-Pb年龄数据，获得了古老地壳存在的同位素年代学信息。

The new approach of phylochronology, combining molecular dating techniques and the fossil appearance data, makes it possible to explore the origin and early divergence times of myriapods as well as the event of animal landing.

谱系年代学综合了化石记录和分子定年两方面的优势，为更加精确地讨论多足动物起源、内部类群分歧时间及其地质背景奠定了基础。

Combined with previous studies, we suggest that the 1100-2200 Ma zircons perhaps originate from the China North Craton, while the zircons of 520 Ma may stem from Jiamusi massif.

根据目前有关年代学研究成果，推断1100~2200 Ma碎屑锆石可能来源于华北克拉通，而样品中的520 Ma的碎屑锆石则可能来源于佳木斯地块。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了