Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1029/2018GL077343 |
Controls on Early-Rift Geometry: New Perspectives From the Bilila-Mtakataka Fault, Malawi | |
Hodge, M.1; Fagereng, A.1; Biggs, J.2; Mdala, H.3 | |
2018-05-16 | |
发表期刊 | GEOPHYSICAL RESEARCH LETTERS |
ISSN | 0094-8276 |
EISSN | 1944-8007 |
出版年 | 2018 |
卷号 | 45期号:9页码:3896-3905 |
文章类型 | Article |
语种 | 英语 |
国家 | Wales; England; Malawi |
英文摘要 | We use the similar to 110-km long Bilila-Mtakataka fault in the amagmatic southern East African Rift, Malawi, to investigate the controls on early-rift geometry at the scale of a major border fault. Morphological variations along the 14 +/- 8-m high scarp define six 10- to 40-km long segments, which are either foliation parallel or oblique to both foliation and the current regional extension direction. As the scarp is neither consistently parallel to foliation nor well oriented for the current regional extension direction, we suggest that the segmented surface expression is related to the local reactivation of well-oriented weak shallow fabrics above a broadly continuous structure at depth. Using a geometrical model, the geometry of the best fitting subsurface structure is consistent with the local strain field from recent seismicity. In conclusion, within this early-rift, preexisting weaknesses only locally control border fault geometry at subsurface. Plain Language Summary This study investigates the controls to fault and rift geometry for a young rift system. Our case study is a large fault in southern Malawi. The geometry of the fault at the surface, the scarp and structures within the rocks the fault cuts through, is measured. We also calculate the scarp height. The orientation and height of the fault scarp implies that local stresses influence its geometry, not regional stresses. We develop a geometrical model to link the scarp and a fault at depth. The best fit model is consistent with the hypothesis that the local stress influences the current fault geometry. We propose that a weak zone at depth may also influence the fault geometry, but weaknesses near the surface only locally influence fault orientation. |
领域 | 气候变化 |
收录类别 | SCI-E |
WOS记录号 | WOS:000434111700017 |
WOS关键词 | EAST-AFRICAN RIFT ; NORTHERN NORTH-SEA ; STRIKE-SLIP FAULTS ; TECTONIC MODEL ; TRANSFER ZONES ; GROWTH ; LINKAGE ; GULF ; SEGMENTATION ; REACTIVATION |
WOS类目 | Geosciences, Multidisciplinary |
WOS研究方向 | Geology |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/27502 |
专题 | 气候变化 |
作者单位 | 1.Cardiff Univ, Sch Earth & Ocean Sci, Cardiff, S Glam, Wales; 2.Univ Bristol, Sch Earth Sci, Bristol, Avon, England; 3.Mzuzu Reg Off, Geol Survey Dept, Mzuzu, Malawi |
推荐引用方式 GB/T 7714 | Hodge, M.,Fagereng, A.,Biggs, J.,et al. Controls on Early-Rift Geometry: New Perspectives From the Bilila-Mtakataka Fault, Malawi[J]. GEOPHYSICAL RESEARCH LETTERS,2018,45(9):3896-3905. |
APA | Hodge, M.,Fagereng, A.,Biggs, J.,&Mdala, H..(2018).Controls on Early-Rift Geometry: New Perspectives From the Bilila-Mtakataka Fault, Malawi.GEOPHYSICAL RESEARCH LETTERS,45(9),3896-3905. |
MLA | Hodge, M.,et al."Controls on Early-Rift Geometry: New Perspectives From the Bilila-Mtakataka Fault, Malawi".GEOPHYSICAL RESEARCH LETTERS 45.9(2018):3896-3905. |
条目包含的文件 | 条目无相关文件。 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论