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Oblique rift opening revealed by reoccurring magma injection in central Iceland.

ABSTRACT: Extension deficit builds up over centuries at divergent plate boundaries and is recurrently removed during rifting events, accompanied by magma intrusions and transient metre-scale deformation. However, information on transient near-field deformation has rarely been captured, hindering progress in understanding rifting mechanisms and evolution. Here we show new evidence of oblique rift opening during a rifting event influenced by pre-existing fractures and two centuries of extension deficit accumulation. This event originated from the Bárðarbunga caldera and led to the largest basaltic eruption in Iceland in >200 years. The results show that the opening was initially accompanied by left-lateral shear that ceased with increasing opening. Our results imply that pre-existing fractures play a key role in controlling oblique rift opening at divergent plate boundaries.

SUBMITTER: Ruch J

PROVIDER: S-EPMC4980445 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Oblique rift opening revealed by reoccurring magma injection in central Iceland.

Ruch Joël J Wang Teng T Xu Wenbin W Hensch Martin M Jónsson Sigurjón S

Nature communications 20160805

Extension deficit builds up over centuries at divergent plate boundaries and is recurrently removed during rifting events, accompanied by magma intrusions and transient metre-scale deformation. However, information on transient near-field deformation has rarely been captured, hindering progress in understanding rifting mechanisms and evolution. Here we show new evidence of oblique rift opening during a rifting event influenced by pre-existing fractures and two centuries of extension deficit accu ...[more]

PMID: 27492709

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