Distribution of large-scale detachment faults on mid-ocean ridges in relation to spreading rates

IOCAS-IR

	Distribution of large-scale detachment faults on mid-ocean ridges in relation to spreading rates
	YU Zhiteng ; LI Jiabiao ; LIANG Yuyang ; HAN Xiqiu ; ZHANG Jie; ZHU Lei
发表期刊	Acta Oceanologica Sinica
ISSN	0253-505X
	2013-12-15
出版年	2013
卷号	v.32 期号:12 页码:111-119
文献类型	CNKI期刊论文
摘要	Large-scale detachment faults on mid-ocean ridges(MORs)provide a window into the deeper earth.They have megamullion on their corrugated surfaces,with exposed lower crustal and upper mantle rocks,relatively high residual Bouguer gravity anomaly and P-wave velocity,and are commonly associated with oceanic core complex.According to 30 detachment faults identified on MORs,we found that their distances to the axis mostly range from 5 to 50 km,half-spreading rates range from 6.8 to 17 mm/a,and activity time ranges from recent to 3 Ma.Most of the detachment faults are developed on the slow spreading Mid-Atlantic Ridge(MAR)and ultra-slow spreading Southwest Indian Ridge(SWIR),with the dominant half-spreading rates of7–13 mm/a,especially 10–13 mm/a.Furthermore,they mostly occur at the inside corner of one segment end and result in an asymmetric seafloor spreading.The detachment faults on MORs are mainly controlled by the tectonism and influenced by the magmatism.Long-lived detachment faults tend to be formed where the ridge magma supply is at a moderate level,although the tectonism is a first-order controlling factor.At the slow spreading ridges,detachment faults tend to occur where local magma supply is relatively low,whilst at the ultra-slow spreading ridges,they normally occur where local magma supply is relatively high.These faults are accompanied by hydrothermal activities,with their relationships being useful in the study of hydrothermal polymetallic sulfides and their origin.
关键词	detachment faults oceanic core complex spreading rates distribution tectonism magma supply hydrothermal vents
CNKI专辑号	A;
CNKI专辑名称	基础科学;
CNKI专题号	A010;A011;
CNKI专题名称	海洋学;地质学;
分类号	P736
收录类别	中科院核心 ; 中科院扩展
语种	英文;
资助项目(基金）	The National Natural Science Foundation of China under contract Nos 91028006 and 41206046 ; the Dayang 115 under contact No.DYXM-115-02-3-01
文献类型	CNKI期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/190623
专题	中国科学院海洋研究所
作者单位	1.KeyLaboratoryofSubmarineGeosciences,StateOceanicAdministration 2.TheSecondInstituteofOceanography,StateOceanicAdministration 3.InstituteofOceanology,ChineseAcademyofSciences 4.ChinaOceanMineralResourcesResearchandDevelopmentAssociation
推荐引用方式 GB/T 7714	YU Zhiteng,LI Jiabiao,LIANG Yuyang,et al. Distribution of large-scale detachment faults on mid-ocean ridges in relation to spreading rates. 2013.