地质科学2017，Vol.52Issue(3)：668-692,25.DOI:10.12017/dzkx.2017.043
全球海山玄武岩数据挖掘研究
The study of global seamount basalt data mining
摘要
Abstract
The seamount is a landform term,usually divided into two categories,one is exposed above sea level,another is covered in it.Seamount have complex causes and it can be produced in different tectonic environment,mainly including:The ocean-island basalt (OIB),mid-ocean ridge basalt (MORB),back-arc basin basalt (BABB),island arc basalt (IAB),continental marginal basalt (CMB),etc.In this paper,the research shows that the geochemical characteristics of the CMB and OIB are nearly similar,and there are some similarities and differences of them in the cause.The OIB is the product of intra-plate magmatic activities,which is generally thought that related to "hot spots" or "mantle plume":While the CMB may be formed by shallow recycling of ancient continental lithosphere and young oceanic crust.Therefore,the shallow recycling of ancient continental lithosphere and young oceanic crust also plays an important role in the process of the formation of the mountain and ocean island volcano besides the "hot spots".Samples from the IAB have characteristic deletion in Nb,Ta and enrichment in some large ion lithophile elements,such as Nb,Ta,P and Ti etc,which shows that the formation of the IAB is related to the subduction.Research suggests that there may be three types hotspots on earth:the first kind is Primary hotspots,which originate from deep mantle:The second type is secondary hotspots,possibly coming from the top of the superplume.Third type hotspots may have a superficial origin,linked to tensile stresses in the lithosphere and decompression melting.As a result,the cause of the seamount can not be explained perfectly by "mantle plume" mode,it should also consider the influence of other factors (such as recycling of the young oceanic crust and old continental crust,subduction sediment and the addition of water,the degree of partial melting,mantle magma mingling,the mixing of the different end member component of mantle,etc.).关键词
海山/洋岛/岛弧/陆缘/OIB/IAB/CMBKey words
Seamounts/Ocean island/Island arc/Continental margin/OIB/IAB/CMB分类
天文与地球科学引用本文复制引用
杜雪亮,张旗,王金荣,陈万峰,潘振杰,李玉琼..全球海山玄武岩数据挖掘研究[J].地质科学,2017,52(3):668-692,25.基金项目
甘肃省西部矿产资源重点实验室(兰州大学)开放项目(编号:MRWCGS-2016-04)资助. （兰州大学）
