English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/164393
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:

Title

Enhanced Mantle Upwelling/Melting Caused Segment Propagation, Oceanic Core Complex Die Off, and the Death of a Transform Fault: The Mid‐Atlantic Ridge at 21.5°N

AuthorsDannowski, A.; Morgan, J. Phipps; Grevemeyer, Ingo; Ranero, César R.
Issue DateFeb-2018
PublisherAmerican Geophysical Union
CitationJournal of Geophysical Research. Solid Earth 123(2): 941-956 (2018)
AbstractCrustal structure provides the key to understand the interplay of magmatism and tectonism, while oceanic crust is constructed at Mid‐Ocean Ridges (MORs). At slow spreading rates, magmatic processes dominate central areas of MOR segments, whereas segment ends are highly tectonized. The TAMMAR segment at the Mid‐Atlantic Ridge (MAR) between 21°25′N and 22°N is a magmatically active segment. At ~4.5 Ma this segment started to propagate south, causing the termination of the transform fault at 21°40′N. This stopped long‐lived detachment faulting and caused the migration of the ridge offset to the south. Here a segment center with a high magmatic budget has replaced a transform fault region with limited magma supply. We present results from seismic refraction profiles that mapped the crustal structure across the ridge crest of the TAMMAR segment. Seismic data yield crustal structure changes at the segment center as a function of melt supply. Seismic Layer 3 underwent profound changes in thickness and became rapidly thicker ~5 Ma. This correlates with the observed “Bull's Eye” gravimetric anomaly in that region. Our observations support a temporal change from thick lithosphere with oceanic core complex formation and transform faulting to thin lithosphere with focused mantle upwelling and segment growth. Temporal changes in crustal construction are connected to variations in the underlying mantle. We propose that there is a link between the neighboring segments at a larger scale within the asthenosphere, to form a long, highly magmatically active macrosegment, here called the TAMMAR‐Kane Macrosegment
Description16 pages, 6 figures
Publisher version (URL)https://doi.org/10.1002/2017JB014273
URIhttp://hdl.handle.net/10261/164393
DOIhttp://dx.doi.org/10.1002/2017JB014273
E-ISSN2169-9313
Appears in Collections:(ICM) Artículos
Files in This Item:
File Description SizeFormat 
Dannowski_et_al_2018.pdf3,95 MBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.