甘南 零度等温线上的人间仙境

甘南藏族自治州是全国十个藏族自治州之一．地处青藏高原东北边缘,南与四川阿坝州相连,西南与青海黄南州、果洛州接壤,东面和北部与本省陇南、定西、临夏毗邻。以物产丰富、环境优美被称作人间仙境——香巴拉。     

《中国行政区划通史·唐代卷》评述

正周振鹤先生主编的《中国行政区划通史》,涵盖先秦至民国,共分十二卷,部分卷次已陆续出版。2012年,终于等到了由郭声波教授执笔的"唐代卷"的问世。陶潜有句,"奇文共赏",阅读之余,有几点想法与学界诸君共享。     

在加利福尼亚收获阳光

在美国加利福尼亚州的莫哈韦沙漠保护区内靠近内华达州界、距离拉斯维加斯约65公里的地方,有一个面积为13平方公里的世界上最大的太阳能热力发电系统,名为“艾文帕太阳能发电系统”（Ivanpah Solar Electric Generating System）。这里每年大约有330-350天都拥有充足的阳光,因而是太阳能发电的理想之所。     

波浪谷

帕里亚峡谷（Paria Canyon）跨越美国犹他州和亚利桑那州,在这片由悬崖、峡谷,山丘组成的区域里,隐藏着一个名叫波浪谷的大自然砂岩雕塑艺术品。     

黔东南从江隐伏似花岗斑岩的发现及其找矿意义

贵州省黔东南州从江县境内构造-岩浆活动极为发育,出露有基性-超基性岩(分布在大弄-加棒-大花孖一带)、基性火山岩(分布在雨田山-帮富山及党扭-平正一带)、中性闪长侵入岩(分布在大弄一带)、酸性花岗岩(分布在摩天岭一带),其中摩天岭花岗岩体(桂北称三防岩     

美国蒙大拿州惊现恐龙木乃伊

近日,在美国蒙大拿州出土一具7700万年前的恐龙木乃伊,这只命名为莱昂纳多（Leonardo）的恐龙为鸭嘴龙 （brachylophosaurus）,它的出土震惊了整个古生物界,令人惊讶的是,其骨骼化石的外围包有软组织——     

http://www.sciencedirect.com/science/article/pii/S167498711200148X

The Earth was born from a giant impact at 4.56 Ga. It is generally thought that the Earth subsequently cooled, and hence shrunk, over geologic time. However, if the Earth's convection was double-layered, there must have been a peak of expansion during uni-directional cooling. We computed the expansion-contraction effect using first principles mineral physics data. The result shows a radius about 120 km larger than that of the present Earth immediately after the consolidation of the magma-ocean on the surface, and subsequent shrinkage of about 110 km in radius within about 10 m.y., followed by gradual expansion of 11 km in radius due to radiogenic heating in the lower mantle in spite of cooling in the upper mantle in the Archean. This was due to double-layered convection in the Archean with final collapse of overturn with contraction of about 8 km in radius, presumably by the end of the Archean. Since then, the Earth has gradually cooled down to reduce its radius by around 12 km. Geologic evidence supports the late Archean mantle overturn ca. 2.6 Ga, such as the global distribution of super-liquidus flood basalts on nearly all cratonic fragments (>35 examples). If our inference is correct, the surface environment of the Earth must have undergone extensive volcanism and emergence of local landmasses, because of the thin ocean cover (3–5 km thickness). Global unconformity appeared in cratonic fragments with stromatolite back to 2.9 Ga with a peak at 2.6 Ga. The global magmatism brought extensive crustal melting to yield explosive felsic volcanism to transport volcanic ash into the stratosphere during the catastrophic mantle overturn. This event seems to be recorded by sulfur mass-independent fractionation (SMIF) at 2.6 Ga. During the mantle overturn, a number of mantle plumes penetrated into the upper mantle and caused local upward doming of by ca. 2–3 km which raised local landmasses above sea-level. The consequent increase of atmospheric oxygen enabled life evolution from prokaryotes to eukaryotes by 2.1 Ga, or even earlier in the Earth history.     

声学地层剖面探测技术在金州湾人工岛场址勘察中的应用

声学地层剖面探测是一种基于声学原理的连续走航式探测水下地层结构和构造的地球物理方法,由于其灵敏度和分辨率高、连续性好且能高效地探测水下地层的地质特征及其分布而在海洋工程勘察中得到了广泛应用.拟在渤海金州湾海域内建造一座人工岛,场址沉积的地层是自晚更新世以来伴随着海平面升降和海侵海退过程而逐渐形成的,自上而下依次为:浅海...     

Did natural fission of 235U in the earth lead to formation of the supercontinent Columbia?

Steady decline in the percentage of 235U in terrestrial uranium made natural fission impossible after about 1.8 Ga.Fission before 1.8 Ga disturbed the lead isotope system at various places worldwide,su...     

白垩纪的吞龙巨鳄:恐鳄

故事傍晚时分,斜阳的光芒越过树梢洒在池塘上。一大群副栉龙正在池塘边饮水,现在是距今7600万年前的白垩纪时期,这片池塘位于今天美国的蒙大拿州。副栉龙们都是吵闹的大家伙,它们能够通过脑袋后面长长的骨管发出响亮的声音,所以在很远的地方就能够听到它们的叫声。副栉龙属于鸭嘴龙类,是典型的植食性恐龙,它们不仅吃树叶,还会吃水中的水草和藻类植物。