显生宙全球气候变化与生物绝灭事件的联系     

陈旭 Bouc.  AJ 《地学前缘》1997,4(3):123-128

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弧下地幔流体和熔体的富集：来自岛弧玄武岩Nb／Ta变化方面的证据     

Stolz  AJ 阴翠珍 《世界地质》1997,16(2):7-10,15

由消减大陆边缘火山沉积岩与洋中脊和大洋岛的玄武岩对比可知，前者最明显的特征是高场强元素Ｎｂ、Ｔａ相对于大离子亲石元素Ｔｉ和轻稀土来说明显亏损。搞清这个问题的主要障碍是缺乏高场强元素（特别是Ｎｂ和Ｔａ）的高质量的分析数据，因为在大多数消减大陆边缘火山岩中其富集程度均很低。本文发表的是岛弧火山岩以及一些海底沉积物中Ｎｂ、Ｔａ的新分析结果。数据表明，Ｎｂ、Ｔａ亏损的岛弧火山岩的Ｎｂ／Ｔａ值，与大洋中脊火  相似文献   

Differential sensitivity of flounder (Platichthys flesus) in response to oestrogenic chemical exposure: an issue for design and interpretation of monitoring and research programmes     

Kirby MF  Smith AJ  Barry J  Katsiadaki I  Lyons B  Scott AP 《Marine environmental research》2006,62(4):315-325

This study was conducted as an initial investigation of 'differential response' in one of the main sentinel organisms used for monitoring programmes in United Kingdom estuaries, the flounder Platichthys flesus. It has been hypothesised that monitoring using species with a wide geographical spread and limited migration, such as flounder, might result in the comparison of different genetic stocks and certainly of populations with differing early life stage contaminant exposure histories. Furthermore, it is probable that these pre-exposure and genetic differences could manifest themselves in an ability to respond differently to contaminant exposure, so-called 'differential response'. It is important that the extent and nature of this response is understood, if we want to be able to fully interpret the monitoring data from such programmes. During this study, flounder were collected from four separate sources; wild caught fish from the estuaries of the Rivers Alde, Mersey and Tyne, and farmed flounder from Port Erin Farm, Isle of Man. Under controlled laboratory conditions, groups of fish from each source were exposed to water-borne concentrations of the synthetic oestrogen ethynylestradiol (EE2) at a nominal concentration of 50 ng/l. Plasma was taken from each male fish after 6 and 10 days exposure and analysed for the presence of vitellogenin (VTG) using an ELISA technique. Significant levels of VTG induction were evident in fish from all sources after both 6 and 10 days exposure. Flounder from the Mersey were the only fish with significantly elevated initial background levels of VTG (day 0) and this appeared to be reflected in that these specimens showed the highest induction response after day 6. However, after day 10, fish from all other sites had a slightly higher mean VTG than those from the Mersey which showed significantly (p < 0.05) lower mean plasma VTG. It is suggested that other differential responses may have been masked by the use of a high dose of EE2 which produced maximum induction in nearly all fish. The findings of the study are discussed in terms of implications for further research into the differential response issue and how the initial plasma VTG figures contribute to a time-series from the Mersey, Tyne and Alde estuaries.  相似文献   

Patterns of literacy in the People's Republic of China     

Jowett AJ 《GeoJournal》1989,18(4):417-427

The recent publication of data from the 1982 census permits an assessment of the patterns, progress and problems of illiteracy in China. Educational progress, since the communists came to power in 1949, has been particularly impressive, especially in relation to the low levels of income within the People's Republic. Nevertheless, nearly a third of the country's population are still unable to read and write and major variations in literacy exist between the developed and less developed regions, between men and women, between the urban and rural areas, between the various age groups and among the many ethnic groups that constitute the People's Republic of China. Among the most favoured people and places, literacy rates exceed 90% but among the most disadvantaged groups, retired women in rural areas for example, levels of literacy fall below 3%. Proposed educational reforms, targeted to provide nine years of compulsory education, offer the potential for boosting literacy levels and breaking the bondage of ignorance. However, such proposals are being undermined by the recent economic reforms in rural China. By stressing the value of labour, including child labour, the agricultural responsibility system has generated a surprising decline in school attendance which may jeopardise future improvements in literacy, particularly so among the poorer people in the poorer areas of China.  相似文献   

日本的找矿钻探     

佐藤彬  白桦 《地质科技情报》1988,(4)

找矿钻探是以掌握矿床赋存状况为最终目的些情报趋于正确而详纽。十了验证它们的模式,作的。这类钻探在探查地下深部的这一点上,  相似文献   

原地应力测量的置信度范围     

Jupe  AJ 关伟沂 《地壳构造与地壳应力》1995,(5):32-36

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层理侵入体中的铂族元素富集模式     

Nald.  AJ 李朋 《地质地球化学》1991,(6):47-55

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盆地山岭正断层的分段：以爱达荷中东部和蒙塔那西南部为例     

Crone  AJ 张杰 《地震译文集》1991,(2):21-32

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澳大利亚维多利亚州肭屏半岛第四纪古土壤沉积物的初步研究     

周利平詹姆.  AJ 《中国沙漠》1994,14(1):52-59

本文对澳大利亚维多利亚州肭屏（Ｎｅｐｅａｎ）半岛海岸悬崖风成岩古土壤序列沉积学地层的成土母质来源、成土时期的环境、时代等问题进行研究。  相似文献   

真的发现了海底热水矿床?     

白桦 《地质科技情报》1985,(2)

据1983年12月28日日本京都新闻报道,日本科学技术厅海洋科学技术中心,于12月27日在青森县海域的日本海海底真的看见了含有铁与钢等金属的、成为21世纪最有希望资源的热水矿床的喷出.发现地点在西津轻郡深浦盯卢作崎西方约70公里.该技术中心为调查1983年日本海中部发生的地震震源,使用无人操纵电视摄影机于水深约3000米处海底摄影时,发现约有15平方公里范围热水在喷出.热水喷出直  相似文献