Abstract
Large-offset oceanic detachment faults are a characteristic of slow- and ultraslow-spreading ridges, leading to the formation of oceanic core complexes (OCCs) that expose upper mantle and lower crustal rocks on the seafloor. The lithospheric extension accommodated by these structures is now recognized as a fundamentally distinct “detachment-mode” of seafloor spreading compared to classical magmatic accretion. Here we demonstrate a paleomagnetic methodology that allows unequivocal recognition of detachment-mode seafloor spreading in ancient ophiolites and apply this to a potential Jurassic detachment fault system in the Mirdita ophiolite (Albania). We show that footwall and hanging wall blocks either side of an inferred detachment have significantly different magnetizations that can only be explained by relative rotation during seafloor spreading. The style of rotation is shown to be identical to rolling hinge footwall rotation documented recently in OCCs in the Atlantic, confirming that detachment-mode spreading operated at least as far back as the Jurassic.
DOI
10.1038/srep02336
Publication Date
2013-08-01
Publication Title
Scientific Reports
Volume
3
ISSN
2045-2322
Organisational Unit
School of Geography, Earth and Environmental Sciences
Keywords
Geodynamics, Geology, Palaeomagnetism, Tectonics
Recommended Citation
Maffione, M., Morris, A., & Anderson, M. (2013) 'Recognizing detachment-mode seafloor spreading in the deep geological past.', Scientific Reports, 3. Available at: https://doi.org/10.1038/srep02336
