Seascape Alaska 6: Gulf of Alaska Transit Mapping



September 23 - October 14, 2023


NOAA Ship Okeanos Explorer


Gulf of Alaska, west coasts of British Columbia and Washington, Oregon, and California

Primary goal

Increase mapping coverage in unexplored U.S. and international waters off the U.S. West Coast, with a focus on waters deeper than 200 meters (656 feet)

Primary technology

Multibeam sonar

Expedition Summary

From September 23 to October 14, NOAA Ocean Exploration conducted the final expedition in the Seascape Alaska series on NOAA Ship Okeanos Explorer, mapping nearly 48,000 square kilometers (18,530 square miles) of seafloor along the West Coast while transiting from Alaska to California.

During mapping operations, NOAA Ocean Exploration collected multibeam sonar bathymetry, made observations of biologic material in the water column using a split-beam fisheries sonar, and made sub-bottom profiler observations of sub-seafloor geologic structure and sediment.

The team mapped a total of 47,899 square kilometers (18,494 square miles) of seafloor, covering a distance of 3,216 kilometers (1,998 miles). Highlights included mapping a portion of the Surveyor Channel in the Gulf of Alaska, discovering a chain of six mounds off the coast of British Columbia that were not visible in existing satellite altimetry data, completing a focused survey in the Cascadia Margin off the coast of Washington that improved data quality in a region of interest for geological hazards, and mapping five mounds off the coast of California that were previously only resolved through low-resolution satellite altimetry.

In the spirit and mission of outreach and education, the team hosted three explorers-in-training during the expedition and held a live interaction through the NOAA Live! Alaska webinar series that reached nearly 700 people, more than 600 of whom were students.

Bathymetric data collected during Seascape Alaska 6 expedition. Background image Digital Elevation Model from Esri, HERE, Garmin, FAO, NOAA, U.S. Geological Survey, and Environmental Protection Agency. Image courtesy of NOAA Ocean Exploration, Seascape Alaska. Download largest version (jpg, 1.6 MB).

Education Content

Education theme pages provide the best of what the NOAA Ocean Exploration website has to offer to support educators in the classroom during this expedition. Each theme page includes expedition features, lessons, multimedia, career information, and associated past expeditions.

Exploration Team

View all

Naming every participant in a telepresence-enabled expedition is next to impossible, as scientists from around the world have provided input into the expedition plan. However, we've assembled information about the members of the team who are sailing on the ship and participating in the expedition from sea – meet the team!

LTJG Abby Letts

LTJG Abby Letts

Technical Operations Team Lead and Expedition Coordinator

Trish Albano

Trish Albano

Expedition Coordinator

Adrianna Ebrahim

Adrianna Ebrahim


Shannon Hoy

Shannon Hoy

Expedition Coordinator Team Lead

Fernando Aragon

Fernando Aragon

Data Engineer

Media Contacts

Emily Crum

Communication Specialist
NOAA Ocean Exploration

Keeley Belva

Public Affairs Officer
NOAA Office of Marine and Aviation Operations

For more information, visit the Media Resources page.

NOAA Ocean Exploration’s 2023 Seascape Alaska expeditions will contribute to the National Strategy for Exploring, Mapping, and Characterizing the United States Exclusive Economic Zone, Seabed 2030, and multipartner Seascape Alaska campaign, which has been endorsed by the Intergovernmental Oceanographic Commission of UNESCO as part of the United Nations Decade of Ocean Science for Sustainable Development 2021-2030.

Data collected during all expeditions will be available in NOAA’s public data archives within 90-120 days of its completion and will be accessible via the NOAA Ocean Exploration Data Atlas.

Published November 30, 2023

2021-2030 United Nations Decade of Ocean Science for Sustainable Development | Seascape Alaska