【摘 要】
：
Helium isotope compositions of the mantle xenoliths and megacrysts in the Cenozoic basalts in the eastern China were measured. The samples were collected from L
【机 构】
：
Institute of Mineral Resources
论文部分内容阅读
Helium isotope compositions of the mantle xenoliths and megacrysts in the Cenozoic basalts in the eastern China were measured. The samples were collected from Ludao of Heilongjiang, Huinan and Jiaohe of Jilin, Kuandian of Liaoning, Hannuoba of Hebei, Nüshan of Anhui, Dingan of Hainan. The 3He/4He ratios of the mantle xenoliths and megacrysts from the most areas were about 1×10-5 , and were similar to those of the MORB, thus reflecting the characteristics of the MORB-typed depleted mantle. The 3He/4He ratios of the mantle xenoliths from Jiaohe were 4.8×10-6 and the 3He/4He ratios of xenoliths from Hannuoba vary from 0.15×10-6 to 7.4×10-6 , obviously lower than those of the MORB, and even lower than the atmospheric helium isotope ratios, indicating that the continental mantle was strongly replaced in Jiaohe and Hannuoba areas. The helium isotope compositions of the mantle xenoliths and megacrysts in the same region vary in a very wide range. It is inferred that the mantle xenoliths and megacrysts were from different parts of the continental mantle. There were not necessary origin relations between the mantle xenoliths, megacrysts and their host basalts. An extremely high 3He/4He ratio of garnet megacryst from Hannuoba, Hebei was found.
其他文献
目的 观察炎琥宁治疗急性上呼吸道感染的临床效果.方法 设治疗组和对照纽两组各100例病人,观察症状、体征改善的时间.结果 两组疗效比较,在发热、流涕、干咳、扁桃体及咽部充
Geochronology of continental flood basalts sampled from the Emei large igneous province (LIP) on the western margin of the Yangtze platform was investigated by
Using the secondary spinel standard, the authors have precisely measured the Fe3+/∑Fe values of spinels in mantle xenoliths from Cenozoic basalts in eastern Ch
Plant hormones play an important role during higher plant embryogenesis. Auxin is central to the development of vascular tissues, formation of lateral and adven
The process parameters of aluminum alloy ladder bowl with viscous pressure forming and solid metal punch forming were numerically simulated by commercial finite
在全国开展"阳光体育运动"活动的背景下,利用十堰地区高校测试所获得的数据,采用文献资料法、抽样法、数理统计法等方法,对学生的体质健康状况进行综合评价.分析影响十堰地区
当前,我国农村消费水平不断提升,农民消费方式日益科学,但农民消费能力不高、消费倾向偏低、消费满足率低.构建扩大农村居民消费需求长效机制还受农民收入、农村市场、社会保
An Archaeopteryx-like theropod dinosaur newly found from western Liaoning Province in northeastern China would make an unusual, if not unwelcome, gift for the 1
Experiments are reported on the effects of flow intensity, obstacle alignment and cross-section geome try on the equilibrium scour depth around abutments. The e
On the frigid land of Antarctica, a man in a blue jacket and black rain boots was tottering againstalmost blinded by the snowflakes but apparently looking for s