赣西湘东菊花状天青石的特征及其成因   总被引：2，自引：1，他引：2       下载免费PDF全文

方邺森  袁旭音 《岩石矿物学杂志》1993,12(4):341-348

赣西湘东地区的天青石,主要产于下二叠统由生物屑泥晶灰岩或泥灰岩构成的瘤状灰岩中,少数产于钙镁质页岩中。晶体常沿a轴或b轴延伸呈柱状,集合体在三度空间由内向外呈放射状排列,形似盛开的菊花,是一种比较少见的天青石结晶习性。本文通过沉积学、矿物学、地球化学的研究阐述了它的特征和成因,提出它是在成岩作用过程中碳酸盐灰泥中的SrSO_4围绕雏晶或胶态SiO_2核心生长而成。这种天青石的发现不仅具有矿物学和沉积学的意义,而且可作为我国华南地区沉积型海泡石的找矿标志。  相似文献   

Two Early Cretaceous fishes discovered from the most northern area of China: implications for the palaeobiogeography of the Jehol Biota     

Li Xiao‐Bo  Zhang Mei‐Sheng  Wang Yi‐Ni 《Geological Journal》2011,46(4):323-332

From a newly discovered Early Cretaceous fossil site at the Sanlianhe Coal Mine in Tahe County, Heilongjiang Province, the most northern area in China, two freshwater fossil fish had been recovered. This paper reports their classifications and implications regarding the palaeobiogeography of the Jehol Biota. The fish assemblage consists of Yanosteus sp. (Acipenseriforms) and Sinamia sp. (Amiiformes). Both are important members of the well known Jehol Biota, and their occurrence supports the correlation of the Yiliekede Formation at Sanlianhe Coal Mine site with the Jiufotang Formation of West Liaoning. The remains of the Yanosteus sp. from this locality is the first known record of the genus other than in the Yan‐Liao area of China, and the specimens of Sinamia sp. is quite similar to what may be a new species of Sinamia from West Liaoning. The new fossil site represents the most northern site that is undoubtedly part of the extent of the Jehol Biota as currently understood. The northern Great Xing'an Range area is an important region that may link correlations between the Early Cretaceous continental biotas of China, Mongolia and Russia. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

沿黄地区浅层淡水水源地傍河取水技术探讨   总被引：1，自引：0，他引：1  

赵志强  安美艳  赵永安  王合秋  李生清 《山东国土资源》2009,25(12):38-41,45

为开辟区域供水新途径，经过对沿黄地区供水勘察资料的分析研究，认为临黄靠渠区，浅层地下水水质较好。从黄河侧渗补给稳化的角度分析，具备了形成中小型供水水源地的条件，技术可行、经济便利，能够满足该区村镇生活及工矿企业用水需求，是缓解该区供水危机的新途径。  相似文献