A Swiftia polyp with small "pinnae" projections along each tentacle.

Octocorals, in the subclass Alcyonaria, have eight pinnate tentacles, whereas scleractinian corals have six non-pinnate tentacles. The “pinnae” are seen here in the small projections along each tentacle of this Swiftia polyp. Click image for larger view.


Exploring Alaska's Seamounts

July 30 - August 23, 2004

The 2004 Gulf of Alaska Seamount Expedition will use the deep submergence vehicle (DSV) Alvin to explore five large seamounts. Giacomini, Pratt, Welker, Denson, and Dickens seamounts stretch over a 400-nautical-mile section of the northeast Pacific, called the Kodiak-Bowie Seamount Chain. Operating from a base aboard the R/V Atlantis, scientists will dive to depths of up to 3,500 m to conduct a series of biological and geological investigations on these ancient volcanoes.

All four of the Principal Investigators aboard this cruise were part of the Gulf of Alaska Seamount Expedition in 2002, as were other scientific researchers, many of the ship’s crew, the sub’s crew, and the cruise coordinator. The research foci of this mission include:

Background information for this exploration can be found on the left side of the page. Daily updates are included below. More detailed logs and summaries of exploration activities are found on the right.

Updates & Logs
Click images or links below for detailed mission logs.

August 23 log August 23, 2004 The expedition team's excitement about exploring Ely Seamount, (aka the Crater of Doom), is cut short due to a night of angry seas.

August 20 log August 20, 2004 Check out deep-sea spider crabs. Find out how they adapt to depths ranging from 900-3,000 meters.

August 19 log August 19, 2004 Scientists are exploring places never before seen by human eyes. Some of the corals are familiar, while others are completely unknown. Read how scientists name their seamount discoveries.

August 18 log August 18, 2004 Scientists hope to learn the age and composition of seamounts from "fresh" rock samples that have not been exposed to seawater. Dive with DSV Alvin to grab samples from outcrops on the seamount.

August 17 log August 17, 2004 Find out about oxygen-minimum zones and how animals cope with the low oxygen around seamounts.

August 16 log August 16, 2004 Be one of the first to ever set eyes on the Dickens Seamount and view the interesting corals found there.

August 12 log August 12, 2004 See how sponges are an obvious and important component of the sea floor animal community.
August 10 log August 10, 2004 Find out how the bacteria that cause plague, cholera, and all those other nasty diseases are in fact a tiny minority of the bacterial world.

August 9 log August 9, 2004 A scientist collects mucus from a large bamboo coral specimen to see how different coral species harbor specific microbial populations.

August 7 log August 7, 2004 The satellite phone call to the Urban Collaborative Accelerated Program was great! Hearing the reaction of students made the adventure seem even more meaningful.

August 6 log August 6, 2004 DSV Alvin searches Denson Seamount for unaltered, "fresh" rocks to determine the age and chemical composition of the seamounts volcanic flows.

August 5 log August 5, 2004 Experiencing her first dive in Alvin, Catalina Martinez recounts her impressions of this amazing opportunity.

August 4 log August 4, 2004 An expendable bathy thermograph (XBT) transmits temperature data back to the R/V Atlantis every quarter-second as it drops onto the Denson Seamount.

August 2 log August 2, 2004 Cary DeLauder, a teacher from UCAP, offers her perspective on being part of the expedition. Read an interview with former UCAP student Patrick Neumann.

July 31 log July 31, 2004 Atlantis fuels up and begins the two-day trip to Denson Seamount.