Submarine glide blocks from the Lower Cretaceous of the Antarctic Peninsula

Ineson, J.R.. 1985 Submarine glide blocks from the Lower Cretaceous of the Antarctic Peninsula. Sedimentology, 32 (5). 659-670. 10.1111/j.1365-3091.1985.tb00480.x

Full text not available from this repository. (Request a copy)

Abstract/Summary

Isolated exotic blocks of late Jurassic age occur within an undeformed succession of marine Lower Cretaceous back‐arc basin deposits on the west coast of James Ross Island, Antarctica. These flat, tabular slabs range up to 200 × 800 m in cross‐section and lie concordant with the enclosing Cretaceous strata. Although mainly undeformed, one block displays a range of emplacement‐related deformation structures, comparable in many respects to tectonic fabrics produced by simple shear. Emplacement by submarine block gliding is proposed, possibly as the final phase in the evolution of a composite mass transport event. Derivation of such gigantic slabs requires the existence of a steep, highly unstable basin margin during the early Cretaceous. In more complex terranes, differentiation between gravity slides and thrust slices can be difficult. Clearly, internal and marginal disruption of an allochthonous unit is not diagnostic since structures developed within a lithified block during submarine gliding may closely mimic tectonic fabrics. Where contact relationships are ambiguous, emplacement by gravity sliding is suggested by the increasing intensity of internal disruption towards the basal margin and by the style of deformation, reflecting simple shear under low overburden.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1111/j.1365-3091.1985.tb00480.x
ISSN:	0037-0746
NORA Subject Terms:	Earth Sciences
Date made live:	21 May 2019 07:56 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/523389

Actions (login required)

View Item

Document Downloads

More statistics for this item...