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1.
详细研究了西秦岭南带中志留统岩石学特征,对遭受重结晶作用的碳酸盐岩进行了结构成因分类。分析了该区中志留世的沉积环境及变化特征。在该区发现的层孔虫生物礁及其它“浅水”标志,表明志留纪时,为若尔盖微古陆北侧的边缘浅海环境。西部为局限陆棚环境,可分为:局限内陆棚、海湾、礁滩-泻湖-潮坪(孤立台地)等亚环境;东部为开阔陆棚环境,可分为浅海砂滩、内陆棚、外陆棚等亚环境。 相似文献
2.
The early permian reef belt is distributed in the southern side of eastern Kunlun, north area of Qinghai-Tibet Plateau. The
core-reef facies of thc reel extends from Tuosuo Lake to Huashixia. Lots of reef breccia was found at the southern slope of
the mre-reef belt, and to the north of the reef belt there is back-reef limestone. Cacisponges, hydrozoa, bryozoa,Tabulozoa, Tubiphytes and red algae are the main frame-building organisms.Archaeolithoporella, laminated blue-green algaes,Tabulozoa andTubiphytes played a role of binding or encrustating. There are many kinds of epibiont in the mf, including brachiopod, gasterid, foraminifera,
echinoderm and simple coral. The type and the characteristics of the reef-building organisms in eastern Kunlun and Animaqing
are basically thr same as those in the south of Chi 相似文献
3.
We present the results of a re-analysis of a previously published carbon isotope data-set related to coralline sponges in the Caribbean Sea. The original interpretation led to the discrimination between a pre-industrial period, with a signal controlled by solar-induced climatic variations, followed by the industrial era, characterized by a progressive δ13C negative shift due to the massive anthropogenic carbon emissions. Our re-analysis allowed to extract from the raw isotopic data evidence of a solar forcing still visible during the industrial era, with a particular reference to the 88-year Gleissberg periods. These signals are related to slope changes in both the δ13C versus time and the δ13C versus carbon emission curves. 相似文献
4.
The results of paleogeomagnetics and geochemistry of the coral reef in well Nanyong 2 of Nansha Islands showed that the bottom of the black sedimentary interlayer corresponds to the conversion boundary line between Brunhes Postive Polarity and Matuyama Reversed Polarity (B/M) and the cold/warm (19/20) climatic conversion bounds on δ18O curve, 0.78 Ma ago; and the red sedimentary interlayer corresponds to the ReunionⅠpolarity excursion (reversion) of the geomagnetic field, 2.01—2.04 Ma ago. Comparing with the normal light-coloured coral reef rock, the magnetic susceptibility (c), residual magnetization intensity (Mr) and the content of MnO and Fe2O3 of the black sedimentary layer appeared obviously positive abnormity. The magnetic susceptibility (c), residual magnetization intensity (Mr) and the content of Fe2O3 of the red sedimentary layer also appeared positive abnormity. Combining with the analyzing results of paleontology, we hold that this pair of special and typical sedimentary interlayers was relative to the sudden change of paleoclimate, i.e. the global climatic change and its incidental polarity reversal of the geomagnetic field directly affected the living environment of the paleontological species as well as the dispersion and enrichment of some chemical elements, especially the elements sensitive to redox such as Fe and Mn. For example, the elements Fe and Mn concentrated in the glacial period would be largely oxidized and diluted when the climate warmed up suddenly, and the originally oxidized high valence Fe would be condensed again when the climate cooled suddenly. This is possibly one of the important reasons of appearing and disappearing of the red and black sedimentary events of coral reef in well Nanyong 2. 相似文献
5.
浙江省休闲生态型人工鱼礁建设现状与展望 总被引:3,自引:0,他引:3
于2006年对象山、台州、洞头、朱家尖、嵊泗等地进行了人工鱼礁建设状况及效果的调查。通过对浙江省各地人工鱼礁建设地走访所获得资料的分析,概述了浙江沿岸休闲生态型人工鱼礁建设的现状,指出建设和管理中存在的问题,并从社会效益、经济效益、生态效益相统一的角度及浙江省自然海域的特点,就如何科学合理地开展我省的人工鱼礁建设,开发利用海洋,实现可持续发展,进行了探讨,并提出了相应的意见。 相似文献
6.
7.
鄂西-渝东地区生物礁发育特征及油气勘探潜力 总被引:2,自引:0,他引:2
通过对井下和露头中典型生物礁发育特征的对比及对已知潜伏生物礁地震响应特征的分析,对鄂西-渝东地区潜伏生物礁进行了初步预测。研究表明:本区东部晚二叠世入于台、盆过渡相区,具备发育大型台地边缘堤礁的有利条件,西部潜伏区则以发育大量台内点礁为特征;潜伏台内点礁虽然分布随机,但成藏条件优越,而且数量多,资源潜力巨大。 相似文献
8.
丘世钧 《华南师范大学学报(自然科学版)》1985,(1):1
松散堆积物的粒度成分及分布规律与沉积环境息息相关,于潮间带以平台地形出现的现代礁坪对其上的松散堆积物的沉积过程施于深刻的影响.本文就海南岛西北岸邻昌、大铲离岸礁和小铲近岸滩礁礁坪上的松散堆积物的粒度参数和粒度分布的若干特征,探讨它们与沉积环境的关系. 相似文献
9.
10.
珊瑚礁被称为海洋中的“热带雨林”,是海洋生态系统中的核心组成部分之一。珊瑚礁病毒包含珊瑚本身感染的病毒和珊瑚共生生物(如藻类、细菌等)感染的病毒,对于珊瑚礁健康与疾病、生长与死亡起着独特而重要的作用,在维持珊瑚礁生态系统的物质循环和能量流动等生态学功能方面起着潜在作用。由于技术的局限以及关注度较低等原因,有关珊瑚礁病毒的研究较少。近年来,随着高通量测序技术的发展,宏转录组和宏基因组逐渐成为研究珊瑚礁病毒多样性及其生态学功能的重要方法之一。本文对国内外相关研究进行总结和归纳,拟为珊瑚礁病毒后续研究提供新的方向和思路,同时指导我国珊瑚礁的保护以及修复。 相似文献