greetings
similar to the CSZ there are sections of this subduction zone where the upper
plate faults switch vergence (the direction updip: landward vergence = updip
towards land; seawrd vergence = updip towards sea: the megathrust -- main fault
-- of the subduction zone is seaward vergent). ou first coring location was a
chanel system in the north in a landward vergent section. we had reasonable
results (russel wynn, turbidite sedimentologist from england) with ~15+ mud
turbidites. the folds are low angle and lesser erosion provides lower volume
turbidites. our second channel system was in a seaward vergent section. the
folds in this section loook like boxwork sandstone cliffs, providing ample sandy
sediment for turbidites, but we had terrible luck recovering much more than a
few decimeters in our cores (remember that we broke several of the sheaves that
we use to operate the main crane/winch that deploys our best coring device : the
piston corer: the piston corer uses suction and a trigger core to give us the
best penetration and the longest cores up to 20-30 feet; we are left with using
the aft a frame and 10' cores). sometime in the last 36 hrs (can't remember days
right now, still doing 16-20 hr shifts), we went to a piggy-back basin up on the
slope of the upper plate, in about 1/2 water depth fo the abysal plain (~1900m).
we had great luck retrieving cores here, found several ashes, can't wait to xrf
them. but... we also found stratigraphy that is difficult to interpret (no good
contacts, very gradual, no blatant turbidites). next we went to a channle system
in the next landward vergent section. here we had great luck acquiring the
longest core since channel 1 (HBO, where we wrote our own version fo six feet
under).
we are now transiting to the last landward vergent channel system before we pass
the rupture boundary between the 2004 and 2005 eqs. (simileue island).
i have been spending much of my time doing site planning, ship planning (telling
the bridge where we want to go, how fast, requesting crew, etc.), and assisting
the coring crew on deck. i am very tired (not conplainging as i am having the
time of my life, love it). eating mucho-vitamino. i am not going hungry... yet.
we pass the equator soon, where i will be indoctrinated to sea going farers
(basically, there is a ceremony where neptune does stuff, and the newbies are
calle dwogs and do penance of sorts, just hope they dont pour gallons of porkfat
al over me.).
you can find webcams on the ship's web page. google "scripps revelle ship", or
something like that, to get to the web page. the co-PI, joe stoner, not from
humboldt, his finace has told joe that she has seen me quite frequently in the
computer lab (our planning area) and on the aft deck coring. she told joe i am
not getting enough sleep. she is porbably right. there is usually (during good
stellite conditions) a ten second cycle on the refresh rate.
love you all, jay
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