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滇东北上二叠统煤系火山碎屑岩特征及意义 被引量:1
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作者 李聪聪 郭英海 +2 位作者 孙顺新 张光超 乔军伟 《中国煤炭地质》 2015年第7期11-14,共4页
上二叠统煤系是滇东北地区主要的含煤岩系,该含煤组合是在晚二叠世早期峨眉山玄武岩喷发的基础上沉积形成的,间歇的火山活动贯穿了整个晚二叠世含煤地层沉积的过程。以研究区及邻区以往研究成果为基础,结合野外地质调查、钻探等资料,对... 上二叠统煤系是滇东北地区主要的含煤岩系,该含煤组合是在晚二叠世早期峨眉山玄武岩喷发的基础上沉积形成的,间歇的火山活动贯穿了整个晚二叠世含煤地层沉积的过程。以研究区及邻区以往研究成果为基础,结合野外地质调查、钻探等资料,对含煤地层中火山碎屑岩发育特征及其对聚煤作用和煤系矿产的指示意义进行了分析,认为该区晚二叠统含煤地层中火山碎屑岩从下至上大致分为三类:凝灰岩、凝灰质泥岩及高岭石泥岩(Tonsteins),且符合从西向东层数逐渐减少,厚度逐渐变薄的规律,揭示了从早期到晚期火山活动逐渐减弱。同时火山碎屑岩是煤系矿产稀散元素(镓、铌)的赋矿层位,其对应的自然伽马曲线呈现高异常,建议下一步工作中注意煤系矿产的调查研究。 展开更多
关键词 滇东北 晚二叠统 火山碎屑岩
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贵州省盘县晚二叠纪聚煤规律研究
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作者 邵银川 《山东国土资源》 2016年第7期1-6,共6页
基于层序地层研究,区内聚煤作用主要发育于三级层序SQ1,SQ3,SQ4海侵体系域中,发育"根土岩—煤—粉砂岩/泥质粉砂岩/粉砂质泥岩/石灰岩"序列。海侵作用早中期,较高的泥炭堆积速率与可容纳空间增加速率相平衡,沉积了区域稳定分... 基于层序地层研究,区内聚煤作用主要发育于三级层序SQ1,SQ3,SQ4海侵体系域中,发育"根土岩—煤—粉砂岩/泥质粉砂岩/粉砂质泥岩/石灰岩"序列。海侵作用早中期,较高的泥炭堆积速率与可容纳空间增加速率相平衡,沉积了区域稳定分布的厚煤层6,14和29号煤层,最大海泛面附近的煤层较薄甚至不发育。 展开更多
关键词 晚二叠统 层序地层 海侵体系域 聚煤规律 盘县
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The relationship between species diversity and ecosystem function (productivity) of the late Middle Permian brachiopods community at the region of Hechuan,Chongqing,China
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作者 ZENG Yong JIANG LiJun +5 位作者 KE Yan LU Qian ZHAO Li LIANG JiaDong HU Han LINGHU Bo 《Science China Earth Sciences》 SCIE EI CAS 2012年第8期1248-1254,共7页
The relationship between species diversity and ecosystem function is a hot topic in ecology and environics. This paper investi- gates the evolution of diversity of the late Middle Permian brachiopods community in Hech... The relationship between species diversity and ecosystem function is a hot topic in ecology and environics. This paper investi- gates the evolution of diversity of the late Middle Permian brachiopods community in Hechuan, Chongqing, China, and dis- cusses the relationship between species diversity and community productivity in terms of the geohistorical development. This paper shows that the species diversity is externalized by several indexes, and the relationship between diversity and productiv- ity is too complex to be described by a single assumption. The relationship between species diversity and community produc- tivity is restricted by environment and community evolution. When the community succeeds normally, the relationship be- tween species richness index, species diversity index, and species evenness index to productivity is in linear dependence rela- tion to each other, which is met with the third assumption. But, when the environment interference surpasses the beating capa- bility of the community, not only the community succession will be terminated and be replaced by another one, but also the relationship between species richness index, species diversity index, and species evenness index to productivity is also in- versed to negative correlation by the interference from environment. Only the relationship between ecological dominance and productivity is in linear dependence relation to each other and approximately met with the third assumption. It is illustrated that the assumption that the productivity is in linear dependence relation with diversity should be established on the presupposition that the community succession is normal. 展开更多
关键词 Hechuan area in Chongqing China late Middle Permian brachiopods community species diversity PRODUCTIVITY
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