Geologic Characteristics of Benthic Habitats in Glacier Bay, Southeast Alaska

In April 2004, more than 40 hours of georeferenced submarine digital video was
collected in water depths of 15-370 m in Glacier Bay to (1) ground-truth
existing geophysical data (bathymetry and acoustic reflectance), (2) examine
and record geologic characteristics of the sea floor, and (3) investigate the
relation between substrate types and benthic communities, and (4) construct
predictive maps of sea floor geomorphology and habitat distribution. Common
substrates observed include rock, boulders, cobbles, rippled sand, bioturbated
mud, and extensive beds of living horse mussels and scallops. Four principal
sea-floor geomorphic types are distinguished by using video observations. Their
distribution in lower and central Glacier Bay is predicted using a supervised,
hierarchical decision-tree statistical classification of geophysical data.

[Summary provided by the USGS.]