|
|
|
|
We have since been steadily steaming to the south at a headng of 171 91社区福利s and an average speed of 12 knots, which R/V Atlantis Captain George Silva says will put us in the Hess Deep area by about 7 p.m. Monday, 1,039 miles from where we started.
The days are already proving busy for the Hess Deep expedition's scientific party of 24, eight of us from Duke. One major hub of activity is the computer lab, where some of us are struggling to learn unfamiliar programs while others are wrestling with unfamiliar software.
A big computer challenge is the collection of graphical programs that will be used to-gather an unprecidentedly large montage of digital images along a 21-mile length of cliff face that will be surveyed by the towed underwater sled, Argo II.
Steve Hurst,a former Duke research scientist who is now at the and serves as one of two co-principal investigators on this mission, helped pick the hardware and software components that the imaging system will use, working in consultation with specialists.
During one of our daily 1 p.m. science update briefings, Hurst, who formerly created geological computerized field trips for Duke students and also joined mission chief scientist Jeff Karson on previous 1990 Alvin dives to the same area of Hess Deep, warned of the complexities of the Argo II "mosaicking" system, which everyone must train to use.
Emily Klein, the Duke co-principal investigator who will oversee geochemistry studies on the expedition, is preparing Atlantis's "wet lab" to process all the rock samples that will be brought back from the deep ocean in exterior baskets aboard the manned submarine Alvin.
Located next to the aft hangar where the Alvin is kept between dives, the wet lab has been stocked with large plastic buckets, rock hammers, tape, plastic bags, ink pens, and two large electric rock saws with diamond edged blades - all to prepare samples for shipment back to Duke and other universities.
The hammers, buckets, pens and bags, plus one of the saws, filled three shipping pallets of gear that were sent down from Duke. Klein, and Duke doctoral student Michael Stewart, a geochemist in training,will need those supplies to oversee all aspects of the sample preparations.
In past months, Stewart has been analyzing samples collected during the 1990 expedition for trace elements that could be detected with a Duke mass spectrometer. And he has been searching the scientific literature for similar analyses of samples collected in the Hess Deep vicinity during previous dives.
In collaboration with Klein, he has also worked on as plan to classify and catalog what Alvin brings up, a task scientists call "curation." Once the submarine is hoisted back on deck after each dive, it will be Stewart's job to supervise the unloading of samples.
Meanwhile, doctoral student Daniel Curewitz, who works under Karson's supervision, has been creating detailed maps of Hess Deep from electronic data collected over the World Wide Web from the in La Jolla, Calif. Curewitz has been aided by Peter Rivizzigno as part of his general duties to assist the Duke team with mapping and rock curation.
Carrie Lee, a first year masters student who plans to make the Argo II digital imaging survey a focus of her graduate research, has been putting the final touches on a computerized record-keeping system for the teams that will monitor still images from Atlantis just as the pictures are being collected.
During the Saturday, March 13, 1 p.m. science briefing, held in Atlantis' library, Lee described how she had simplified record keeping logs after consulting with Woods Hole specialists aboard. After the round the clock watches are underway, rotating groups to include all members of the scientific team will take turns recording what Argo is "seeing" about two miles below.
Using a computerized menu of choices, those "event loggers" must act quickly to keep up with images that will arrive every 13 seconds - so rapidly that that some scientists in the room questioned whether the loggers can keep up with the action.
At that same meeting, Duke senior Aisha Morris, whose long-term ambition is to visit other planets and personally study their geology, described her analysis of the photographic records from Karson's and Hurst's 1990 dives.
Morris has been classifying the dimensions, locations, and angles (which geologists call the "dip,") of the array of dikes documented during those dives. These dikes are the now-solidified remains of conduits molten magma once used to move toward the surface back when the Hess Deep study area was located further west at the East Pacific Rise, Karson noted at the same briefing.
Drawing on a white board with a magic marker, Karson said 1990 Alvin dives to the same area that will now be studied in much more detail found a surprisingly complex arrangement of dikes and other geological features.
Those features were not observed by a manned French submarine operating just a few hundred yards from the 1990 Alvin study. Since Hess Deep's wall provides a panorama of past geological times, those observational differences might imply that "oceanic crust is made differently at different times," Karson said.
Karson first proposed returning to Hess Deep in 1994, but didn't get funding until 1996. Problems with ship scheduling pushed the project back another three years. But all those delays had a silver lining: "a decade of technical improvements that is all the better for us," he said during a pause for some fresh tropical air on an upper deck.
Duke's Hess Deep team has been "planning intensely for a year," he added. There were student seminars until a few days before their departure from Raleigh-Durham International Airport early on the morning of March 9, with a winter storm threatening.
There were last minute problems as well. Just two weeks before their departure, Karson learned that the scientific equipment pre-shipped to Long Beach, Calif. had gotten stranded on the docks after the container ship it was to be loaded on left early.
He found out from the secretary who had telephoned for an address to return the equipment to Durham. Scrambling quickly, his group made alternate arrangements to airlift the equipment to Manzanillo.
Then, just one day before they left, an array of ordered computer equipment finally arrived. All that hardware ended up being divided among all but one member of the Duke party as extra carry-on luggage.
The other expedition member, who left the next day on a different route, ended up getting stranded overnight in Guadalajara, Mexico. It took him until the following noon to catch another plane and find his way to the docks.
|
|
|
