Tertiary basaltic pillow lobes at Cape Grim, northwestern Tasmania, Australia display well-preserved spreading cracks in the glassy crust. The spreading cracks are lens-shaped or rectangular in plan view. In cross section, they consist of a graben-like depression with a broad floor bounded by steep scarps. The floor of spreading crack contains an axial crack and a number of ridges that are arranged symmetrically with respect to the axial crack. The ridges within spreading cracks are inferred to have formed by the regular, repeated production and splitting of new crust at the centre of the spreading crack. This new interpretation of ridges in spreading cracks differs from the previous interpretation in which they are regarded as elongate normal fault blocks. Our interpretation provides new insight into the propagation mechanisms of pillow lavas. © 2012 Springer-Verlag.

Item Type:	Refereed Article
Research Division:	Earth Sciences
Research Group:	Geology
Research Field:	Volcanology
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the earth sciences
UTAS Author:	McPhie, J (Professor Jocelyn McPhie)
ID Code:	81916
Year Published:	2012
Funding Support:	Australian Research Council (CE0561595)
Web of Science® Times Cited:	5
Deposited By:	Centre for Ore Deposit Research - CODES CoE
Deposited On:	2013-01-11
Last Modified:	2017-10-30
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