Geomorphology of unique reefs on the western Canadian shelf: sponge reefs mapped by multibeam bathymetry

Multibeam imagery of siliceous sponge reefs (Hexactinellida, Hexactinosida) reveals the setting, form, and organization of five reef complexes on the western Canadian continental shelf. The reefs are built by framework skeleton sponges which trap clay-rich sediments resulting in a distinctive patter...

Full description

Saved in:
Bibliographic Details
Published in:Geo-marine letters 2005-09, Vol.25 (4), p.205-213
Main Authors: Conway, Kim W., Barrie, J. Vaughn, Krautter, Manfred
Format: Article
Language:English
Subjects:
Bathymetry
Continental shelves
Coral reefs
Geology
Geomorphology
Hexactinellida
Marine
Mounds
Ocean floor
Reefs
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Multibeam imagery of siliceous sponge reefs (Hexactinellida, Hexactinosida) reveals the setting, form, and organization of five reef complexes on the western Canadian continental shelf. The reefs are built by framework skeleton sponges which trap clay-rich sediments resulting in a distinctive pattern of low intensity backscatter from the reefs that colonize more reflective glacial sediments of higher backscatter intensity. Bathymetry and backscatter maps show the distribution and form of reefs in two large complexes in the Queen Charlotte Basin (QCB) covering hundreds of km2, and three smaller reef complexes in the Georgia Basin (GB). Ridges up to 7 km long and 21 m in height, together with diversely shaped, coalescing bioherms and biostromes form the principal reef shape in the QCB whereas chains of wave-form, streamlined mounds up to 14 m in height have developed in the GB. Reef initiation is dependent on the distribution of high backscatter-intensity relict glacial surfaces, and the variation in reef complex morphology is probably the result of tidally driven, near seabed currents. [PUBLICATION ABSTRACT]
ISSN:0276-0460
1432-1157
DOI:10.1007/s00367-004-0204-z