thumbnail

Formation of forearc basins by collision between seamounts and accretionary wedges: an example from the New Hebrides subduction zone

Geology

By:
,

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time

Abstract

Seabeam data reveal two deep subcircular reentrants in the lower arc slope of the New Hebrides island arc that may illustrate two stages in the development of a novel type of forearc basin. The Malekula reentrant lies just south of the partly subducted Bougainville seamount. This proximity, as well as the similarity in morphology between the reentrant and an indentation in the lower arc slope off Japan, suggests that the Malekula reentrant formed by the collision of a seamount with the arc. An arcuate fold-thrust belt has formed across the mouth of the reentrant, forming the toe of a new accretionary wedge. The Efate reentrant may show the next stage in basin development. This reentrant lies landward of a lower-slope ridge that may have begun to form as an arcuate fold-thrust belt across the mouth of a reentrant. This belt may have grown by continued accretion at the toe of the wedge, by underplating beneath the reentrant, and by trapping of sediment shed from the island arc. These processes could result in a roughly circular forearc basin. Basins that may have formed by seamount collision lie within the accretionary wedge adjacent to the Aleutian trenches. -Authors

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Formation of forearc basins by collision between seamounts and accretionary wedges: an example from the New Hebrides subduction zone
Series title:
Geology
Volume
17
Issue:
10
Year Published:
1989
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Geology
First page:
930
Last page:
933
Number of Pages:
4