川西北地区晚三叠世卡尼期古喀斯特特征及研究意义
本文选题:晚三叠世 + 卡尼期 ; 参考:《成都理工大学》2017年硕士论文
【摘要】:卡尼期湿润气候事件是三叠纪内最为显著的全球性气候事件,其在中国的川西北地区、贵州、云南等地都被等时地识别出来。卡尼阶在川西北汉旺青岩沟、观音崖剖面以及安县雎水剖面自下而上表现出由生物灰岩到黑色页岩(粉砂质泥岩)的岩性转变。前人认为从生物颗粒灰岩到黑色页岩反映出水体由浅变深的过程。此次在川西北地区绵竹汉旺、安县雎水剖面上三叠统卡尼阶海绵礁(丘)灰岩顶部发现古喀斯特的存在,表明川西北地区的岩层在卡尼期经历过一次暴露,其后水体逐渐变深,而后在喀斯特之上沉积黑色页岩(粉砂质泥岩)。本次研究通过野外剖面勘察、采样及室内薄片分析,古生物化石鉴定等手段,结合国内外卡尼期事件、龙门山构造活动以及喀斯特的研究资料与方法,对卡尼阶剖面中喀斯特的具体形成时代和成因以及其与卡尼事件及龙门山隆升事件之间的关系进行探讨。在野外岩石露头表面可见明显的花斑状构造以及蜂窝状溶孔,显微镜下可见泥晶化颗粒,喀斯特角砾以及喀斯特溶孔充填物,其中包括泥-亮晶方解石,生物碎屑以及陆源石英颗粒。根据露头岩性和显微薄片特征判断其属于早成岩期喀斯特;喀斯特成单层发育,之上覆盖化石丰富的黑色页岩(粉砂质泥岩),其中的菊石化石鉴定表明其为上卡尼阶底部沉积。喀斯特之上的岩性在汉旺和雎水有差异:在绵竹汉旺青岩沟剖面,喀斯特灰岩之上覆盖有黑色粉砂质页岩,在汉旺观音崖剖面,喀斯特面之上发育黑色页岩,在安县雎水剖面,古喀斯特发育在滚落的海绵巨砾之上。化石证据表明该喀斯特的形成时代应在早卡尼期至晚卡尼早期。喀斯特的形成与地层的暴露以及水体的冲刷淋滤有关,而该喀斯特的形成时间与龙门山的隆升以及卡尼期湿润气候事件在发生时间上非常相近;综合研究表明,推测该喀斯特的形成与早期龙门山的隆升以及卡尼期湿润气候事件有关。
[Abstract]:Carney humid climate event is the most significant global climate event in the Triassic. It has been identified in northwestern Sichuan, Guizhou, Yunnan and other places in China. From the bottom to the top of Hanwang Qingyan ditch, Guanyin Cliff section and Anxian Jushui section in northwestern Sichuan, the Karni stage shows lithologic transformation from biolimestone to black shale (silty mudstone). Previous researchers believe that the process from biogranular limestone to black shale reflects the water body from shallow to deep. The discovery of paleokarst on the top of the cavernous reef (mound) limestone of the Triassic Carney terrace in Hanwang Mianzhu, northwestern Sichuan, Anxian Jushui section, shows that the rock strata in the northwestern part of Sichuan experienced an exposure during the Carney period, and then the water gradually deepened. Black shale (silty mudstone) is then deposited on top of karst. In this study, by means of field profile survey, sampling and indoor slice analysis, and identification of paleontological fossils, combined with domestic and foreign Carney events, Longmen Mountain tectonic activities and karst research data and methods, This paper discusses the formation age and origin of karst in Karni stage profile and its relationship with Karni event and Longmen Mountain uplift event. On the surface of outcrops in the field, there are obvious blotchy structures and honeycomb dissolution pores. Under the microscope, there are mud crystals, karst boulders and karst dissolved pore fillings, including mud and bright crystal calcite, Bioclastic and terrestrial quartz particles. According to the characteristics of outcrop lithology and microslice, it belongs to the early diagenetic karst stage, the karst monolayer developed, and covered with rich fossil black shale (silty mudstone). The identification of the permite fossils indicates that it is the bottom deposit of the upper Carney stage. The lithology of karst is different between Hanwang and Ju water: in Mianzhu Hanwang Qingyanggou section, karst limestone is covered with black silty shale, in Hanwang Guanyin Cliff section, black shale is developed above karst surface, and in Anxian Ju Shui section, Ancient karst developed on top of falling spongy boulders. Fossil evidence suggests that the karst was formed from early Carney to early late Carney. The formation of karst is related to the exposure of strata and the erosion and leaching of water body, and the formation time of karst is very close to the uplift of Longmen Mountain and the humid climate event of Carney period. It is speculated that the formation of this karst is related to the uplift of the early Longmen Mountains and the humid climatic events of the Carney period.
【学位授予单位】:成都理工大学
【学位级别】:硕士
【学位授予年份】:2017
【分类号】:P534.51;P642.25
【参考文献】
相关期刊论文 前10条
1 杜怡星;时志强;;川西北地区上三叠统卡尼阶古喀斯特的发现及研究意义[J];沉积学报;2017年03期
2 肖笛;谭秀成;郗爱华;刘宏;山述娇;夏吉文;程遥;连承波;;四川盆地南部中二叠统茅口组碳酸盐岩岩溶特征:古大陆环境下层控型早成岩期岩溶实例[J];古地理学报;2015年04期
3 谭秀成;肖笛;陈景山;李凌;刘宏;;早成岩期喀斯特化研究新进展及意义[J];古地理学报;2015年04期
4 金鑫;时志强;王艳艳;段雄;程明;;晚三叠世中卡尼期极端气候事件:研究进展及存在问题[J];沉积学报;2015年01期
5 金民东;曾伟;谭秀成;李凌;李宗银;罗冰;张静蕾;刘吉伟;;四川磨溪—高石梯地区龙王庙组滩控岩溶型储集层特征及控制因素[J];石油勘探与开发;2014年06期
6 李江海;王洪浩;李维波;周肖贝;;显生宙全球古板块再造及构造演化[J];石油学报;2014年02期
7 张彪;王中蛟;时志强;程明;段雄;金鑫;崔磊;;川西北绵竹汉旺马鞍塘组与小塘子组间不整合面的发现及意义[J];成都理工大学学报(自然科学版);2013年01期
8 王艳艳;张彪;时志强;伊海生;;川西北地区晚三叠世卡尼期洪水事件沉积的碳、氧同位素记录[J];古地理学报;2012年03期
9 李勇;苏德辰;董顺利;孙玮;杨荣军;刘树根;颜照坤;闫亮;;晚三叠世龙门山前陆盆地早期(卡尼期)碳酸盐缓坡和海绵礁的淹没过程与动力机制[J];岩石学报;2011年11期
10 陈洪德;徐胜林;林良彪;侯明才;陈安清;;龙门山造山带晚三叠世构造隆升的分段性及层序充填响应[J];沉积学报;2011年04期
相关硕士学位论文 前2条
1 张彪;川西北地区晚三叠世卡尼期气候事件研究[D];成都理工大学;2013年
2 孟昱璋;四川盆地嘉陵江组岩相古地理与天然气成藏研究[D];成都理工大学;2011年
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