地质科学
     首页 | 过刊浏览 |  本刊介绍 |  编委会 |  投稿指南 |  期刊征订 |  留言板 |  批评建议 |  联系我们 |  English
地质科学  2013, Vol. 48 Issue (2): 384-405    DOI: 10.3969/j.issn.0563-5020.2013.02.005
论文 最新目录 | 下期目录 | 过刊浏览 | 高级检索  |   
藏南碳酸岩脉成因及其气候效应
刘焰
大陆构造与动力学国家重点实验室,中国地质科学院地质研究所 北京 100037
Petrogenesis of carbonic dykes within southern Tibetan Plateau, and climatic effects
Liu Yan
State Key Laboratory of Continental Tectonics and Dynamics, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037
 全文: PDF (10578 KB)   HTML( )   输出: BibTeX | EndNote (RIS)      背景资料
摘要 始新世末期以来,全球大气CO2浓度持续下降,但长期以来不清楚为何这一时期全球大气CO2浓度下降,巨量的大气CO2赋存于何处。深入研究该问题有助于准确理解未来大气CO2浓度变化的趋势,特别是有助于进一步评估人类自身碳排放的后果。这一时期,小印度陆块持续与大亚洲陆块汇聚,导致了以喜马拉雅为代表的山脉群和青藏高原的形成。很早就有学者从地球表层碳循环的角度提出了"青藏高原的隆升导致了全球变冷"的观点,但这一观点既没有解释清楚"巨量大气CO2到何处去"的问题,也没有讨论青藏高原本身向大气圈排放CO2等问题,因此该观点最近受到了强烈的质疑。这些激烈的争论充分反映了传统的地球表层碳循环研究已不能充分满足当前社会的需求。本文从深部碳循环这个视角重新探讨青藏高原在全球碳循环中的作用。在印度与亚洲陆块持续汇聚期间,以喜马拉雅为代表的巨型山脉快速崛起,然后持续遭受化学风化作用,大量消耗大气CO2。化学风化的产物堆积在喜马拉雅山前的前陆盆地内,形成了巨量含新生碳酸盐矿物和有机碳的西瓦里克沉积杂岩,随后新生的西瓦里克杂岩又随持续平板俯冲的印度陆壳被带入青藏高原内部,与平板俯冲的印度陆壳共同经历高温变质作用。俯冲板片内的(黑)云母等含水矿物发生脱水,形成花岗岩浆。花岗岩浆再与俯冲的西瓦里克杂岩内的碳酸盐岩发生交代反应,释放出含钙、镁离子、以CO2和水为主的高温流体,本文称其为壳源火成碳酸岩浆。碳酸岩浆沿张性裂隙上侵、冷凝之后形成藏南的碳酸岩脉。虽然青藏高原内部的火山、温泉等均向大气圈排放CO2,但所排放的碳均为再循环来自大气圈的碳,并且排放量略小于吸收量,否则消耗大气CO2所新生的碳酸岩脉就不会在青藏高原内部保存下来。藏南大量晚新生代碳酸岩脉的发现充分说明了喜马拉雅山脉和藏南高原是一个巨大的碳储库,在其形成过程中将巨量大气CO2转化为流体(岩浆)的形式封存于青藏高原内部,从而大幅降低了大气CO2浓度,最终导致了全球变冷。上述过程充分说明,大气CO2浓度的变化实质上是受控于地球内部的构造运动。进一步可推论出,"全球变化"只是一个自然现象,虽然它有独特的运行轨迹,但与人类的碳排放量无因果关系。
服务
把本文推荐给朋友
加入我的书架
加入引用管理器
E-mail Alert
RSS
作者相关文章
关键词深部碳循环   青藏高原   人类碳排放   碳汇     
Abstract: Global climatic change has become one of the hottest issues worldwide.Knowledge of ancient Earth's surface temperature is critical to understanding Earth today and future as well as evaluating effects of mankind's carbon emissions exactly.Earth's surface average temperature has decreased since the end of the Eocene.It is generally accepted that this long-term global cooling is perhaps a consequence of long-term decreasing of global CO2 concentrations.However,it is still unknown where and how the huge atmospheric CO2 sinked.The hypothesis of global warming in the near future is,therefore,lack of solid evidence when the questions remain unknown.Since the Cenozoic,Indian continent has continuously flighted northwards and hit Asian continent finially,leading to the close of larger Neo-Tethyan Ocean and subsequent uplift of Himalayan Mountains as well as Tibetan Plateau.A "Raymo" hypothesis that the uplift and subquent erosion of the Himalayan-Tibetan orogen has drawn down atmospheric CO2 and cooled the globe is,therefore,present.However,this hypothesis has been recently challenged by the studies of degassing of hot springs within Himalayan Mountains.These scientific arguments have revealed that traditional approaches to surface carbon recycling have hardly satisfied the demands of current society.In this study,the role of Himalayan Mountains and south Tibetan Plateau in the global carbon cycling is re-evaluated.During collision between Indian and Asian continents,the Himalayan Mountains have quickly uplifted and hence underwent stronger chemical weathering,leading to the formation of carbon-rich Siwalik formation within the north of Gange foreland basin to the south of Himalayan Mountains.The carbon-rich Siwalik formation,at the expense of huge atmospheric CO2,has been subsequently transferred into the interior of Tibetan Plateau with flat-subducted Indian crust.Some carbon from the buried Siwalik formation beneath Himalayan Mountains has been released back to atmosphere through hot springs.Most carbon had,however,transferred into deep interior of Tibetan Plateau along with subducted Indian crust.The biotite within the subducted slab underwent dehydration to form granitic magmas beneath south Tibetan Plateau.The metasomatic reactions between the granitic magmas and the subducted carbon-rich Siwalik formation took place to release high-temperature CO2-rich fluids beneath Tibetan Plateau,regarded as crustal-derived carbonic magmas in this study.The magmas/fluids intruded into south Tibetan upper crust to form carbonic dykes.The huge atmospheric CO2 has,therefore,been transformed into carbonic magmas within thickened crust of southern Tibetan Plateau during the collision between India and Asia.The carbon emitted by hot springs as well as volcanoes within Tibetan Plateau was originated from atmosphere.It is recycling carbon.The carbon emissions from Tibetan Plateau are slightly less than those sinked by Tibetan Plateau.Otherwise,the carbonic dykes,formed by consuming huge atmospheric CO2,never occurred within Tibetan Plateau.This clearly suggests that Himalayan Mountains and south Tibetan Plateau are a huge reservoir for atmospheric CO2,leading to global cooling during Cenozoic times.Moreover,the changing of atmospheric CO2 was mainly derived by Earth's tectonic activities,and not by mankind.Global changing is only a natural phenomenon,without any relationships carbon emissions of human.
Key wordsDeep carbon recycling   Tibetan Plateau   Carbon emission   Carbon sinking   
收稿日期: 2012-11-20;
基金资助:

中国地质调查局项目(编号:1212011121271)和国家自然科学基金项目(编号:49802018,40572040)资助

作者简介: 刘焰,男,1969年3月生,博士,研究员,岩石学与构造地质学专业。E-mail:yanliu0315@yahoo.com.cn
引用本文:   
. 2013, 藏南碳酸岩脉成因及其气候效应. 地质科学, 48(2): 384-405.
. Petrogenesis of carbonic dykes within southern Tibetan Plateau, and climatic effects[J]. Chinese Journal of Geology, 2013, 48(2): 384-405.
 
没有本文参考文献
[1] 王师迪 师亚芹 董云鹏. 青藏高原东北缘固关—虢镇断裂中段第四纪以来活动特征[J]. 地质科学, 2018, 53(3): 781-798.
[2] 史小辉 杨 钊 董云鹏 王师迪 周 波. 西秦岭嘉陵江上游瞬时地貌发育特征[J]. 地质科学, 2018, 53(3): 819-834.
[3] 陈天仕 程 斌 董云鹏 王兆国. 南北构造带北段S波分裂研究及其动力学意义[J]. 地质科学, 2018, 53(3): 860-875.
[4] 王 超 刘 良 李荣社. 青藏高原北缘前寒武纪地质演化进展与讨论[J]. 地质科学, 2018, 53(3): 972-999.
[5] 郭进京 吉夏 赵海涛 陆宏宇 王凯旋 韩文峰. 西秦岭北缘漳县韩家沟砾岩对青藏高原东北缘地壳隆升的约束[J]. 地质科学, 2017, 52(4): 1011-1025.
[6] 张洪双, 李秋生, 高锐, 叶卓, 龚辰. 青藏高原东北缘岩石圈-软流圈边界成像[J]. 地质科学, 2016, 51(1): 5-14.
[7] 郭晓玉, 高锐, 徐啸, Keller G R. 基于ALOS-PALSAR卫星数据对青藏高原东缘龙日坝断裂带地表构造伸展的研究及其大地构造指示意义[J]. 地质科学, 2016, 51(1): 15-25.
[8] 郭晓玉, 高锐, Keller G R, 沙爱军, 徐啸, 王海燕, 李文辉. 龙门山断裂带隆起造山独特性探讨[J]. 地质科学, 2014, 49(4): 1337-1345.
[9] 丁林, 钟大赉. 印度与欧亚板块碰撞以来东喜马拉雅构造结的演化[J]. 地质科学, 2013, 48(2): 317-333.
[10] 王二七. 青藏高原大地构造演化——主要构造—热事件的制约及其成因探讨[J]. 地质科学, 2013, 48(2): 334-353.
[11] 杨迪, 丁林. 青藏高原北部白榴碧玄岩年代学及地球化学研究[J]. 地质科学, 2013, 48(2): 449-467.
[12] 徐明1|2 朱传庆1 绕松1|2 胡圣标1. 阿坝—简阳地学剖面深部温度及热结构[J]. 地质科学, 2011, 46(01): 203-212.
[13] 黎敦朋1 赵越2 刘健2 万景林3 郑德文3 潘燕兵2 何哲峰2. 青藏高原西北缘盆山过渡带陡坡地貌的形成时代与成因[J]. 地质科学, 2010, 45(04): 930-943.
[14] 李仕远1,2 王亚东3 张跃中4 方小敏1,3 王九一1,2 刘栋梁1. 柴达木西部地区新生代主控断裂演化过程及其意义[J]. 地质科学, 2010, 45(03): 666-680.
[15] 薛蕾1,2 张振卿1,2 刘维明1,2 吕同艳1,2 孙继敏1. 西藏色林错12ka以来的湖泊退缩过程--基于古湖岸线的OSL测年[J]. 地质科学, 2010, 45(02): 428-439.
 
版权所有 © 2009-2017 《地质科学》编辑部
地址:北京9825信箱  邮政编码:100029
电话:010-82998109  010-82998115
京ICP备05029136号-10