摘要
目前天然富硒土壤评价工作多集中在与人类生活居住有密切关系的覆盖区,在硒源驱动研究方面主要有火山岩型、石煤型、燃煤型、湖潮型、大气降尘型、人工污染型等成因认识,土壤富硒的主因聚焦在硒的次生富集作用与人类活动作用影响上,即聚焦于硒表生循环-地球外动力作用研究,忽略了对地球内动力作用的影响研究。本文以河南省寺河山一带富硒土壤调查评价为基础,广泛收集包括寺河山在内的崤山地区以往所有地质资料,从土壤硒驱动的内、外动力作用同时入手,从宏观尺度上对其驱动机制进行探讨。研究认为,崤山地区土壤Se受热液与断裂构造的双重控制,起源于核幔边界的地幔流体,在自身强大驱动力作用下,携带并沿途不断活化萃取Au、Se等成矿元素,当沿深大断裂上涌进入地壳后则会减压降温由超临界态逐渐相变为热液,开始热液作用形成一系列含Se热液矿产;当到达地表,Se等易被富碳等有机质或富硅等粘土质成分吸附捕获形成含硒土壤,继而进入水圈、大气圈、生物圈等开启表生循环,从而构成一个完整的硒循环过程。在覆盖区因隐伏深大断裂构造不易观察识别而往往被忽略,今后工作中应引起注意。
At present,the assessment of natural Se-rich soil is mainly concentrated in the coverage area that is closely related to human life.In terms of Se source driving research,the Se genesis mainly includes volcanic rock type,stone coal type,cool-fired type,lake tide type,and atmospheric dust type,and artificial pollution type.The main cause of soil Se enrichment basically focuses on the secondary enrichment of selenium and the impact of human activities,that is,focusing on the study of Se supergene cycle-extraterrestrial dynamic action,ignoring the study of the impact on the internal dynamic action of the Earth.Based on the survey and evaluation of Se-rich soil in the area of Sihe Mountain in Henan Province,this work extensively collected geological data of the Xiaoshan area including Sihe Mountain,and discussed the driving mechanism of soil selenium from the perspective of both internal and external driving forces.Results show that the soil Se in Xiaoshan area is controlled by both hydrothermal fluid and fault structure.The mantle fluid originating from the core-mantle boundary,under its own strong driving force,carried and continuously activated the extraction of Au,Se and other oreforming elements along the way up.When mantle fluid upwelled into the crust along the deep fault,it will decompress and cool down gradually from the supercritical state to the hydrothermal fluid,and start hydrothermal process to form a series of Se-containing hydrothermal minerals.When reaching the surface,Se and other elements were easily adsorbed and captured by carbon-rich organic matter,or silicon-rich clay to form selenium-containing soil,and then entered the hydrosphere,atmosphere,and biosphere to start the supergene cycle,thus forming a complete Se cycle process.In overburden area,hidden deep and large faults are often ignored because they are not easy to observe and identify,which should be paid attention to in the future work.
作者
付巧玲
邱顺才
FU Qiaoling;QIU Shuncai(The Fifth Geological Exploration Institute of Henan Geology and Mineral Bureau,Zhengzhou,Henan 450001;The Fourth Geological Exploration Institute of Henan Geology and Mineral Bureau,Zhengzhou,Henan 450001)
出处
《地质与勘探》
CAS
CSCD
北大核心
2023年第3期580-590,共11页
Geology and Exploration
关键词
硒源驱动
地幔流体
深大断裂
崤山地区
河南
Se driving mechanism
mantle fluid
deep fracture
Xiaoshan area
Henan Province
