UPDATE
(5/29 1000PDT): Report from the USCG Healy cruise-No
significant thermal anomalies from hydrothermal plumes were
in the area. Several dredges were collected to recover rocks
from the seafloor, but they were all clearly old. The entire
segment was resurveyed with multibeam sonar to compare with
bathymetry collected before the earthquake swarm. In summary,
Healy also found no evidence for eruption of lava onto the
seafloor.
UPDATE
(5/22 1000PDT): The response effort did not find any
evidence that an eruption occured at Jackson segment during
this seismic event. The earthquake swarm clearly indicated
that magma was moving during this event, but apparently
it never made it up to the seafloor to erupt.
UPDATE
(4/24 0900PDT): USCG
Ship Healy will conduct CTDs and dredges on site (~4/26)
as part of Healy's maiden science shakedown cruise. Chief
Scientist Peter Michaels will send results when available.
UPDATE
(4/19 1155PDT): Map showing the CTD and camera tow locations
now posted on the Response Effort
site.
UPDATE
(4/14 0830PDT): New Horizon reports that after
24 casts,
no plume had been detected and that a bottom camera run
will be attempted next. Without a refined position based
on the plume location, the camera work will be largely reconnaissance.
The ship is scheduled to return to Eureka Monday morning.
UPDATE
(4/13 0930PDT): New Horizon continues exploring
for megaplumes at Gorda Ridge using vertical hydrographic
casts with no plumes detected
after eighteen profiles. Seismicity remains at a very low
level. Coninuation of the effort is being discussed.
UPDATE
(4/12 0930PDT): New Horizon continues exploring
for megaplumes at Gorda Ridge using vertical hydrographic
casts. A broken altimeter prevents using tow-yos. No
plumes have been identified after seven casts. Seismicity
remains at a very low level. Hydrographic effort will move
to the southern portion of the area of activity.
UPDATE
(4/11 1630PDT): New Horizon continues exploring
for megaplumes at Gorda Ridge. The initial vertical hydrographic
cast was "undiagnostic". Seismicity
has decreased to a very low level, perhaps indicating that
it is now below the detection threshold of the T-phase Monitoring
System. Vertical casts will continue through the night.
Ship will report at 0830 with the night's results, which
will be posted immediately.
UPDATE
(4/11 1030PDT): New Horizon arrived onsite at
Gorda Ridge at 3am PDT. The initial vertical hydrographic
cast showed no sign of a plume. Seismicity
continues at a reduced level. Seas are calm (~5ft) and winds
moderate (~15kts). A second vertcal cast is underway.
UPDATE
(4/10 1630PDT): New Horizon is enroute to Gorda
Ridge. Seismicity
continues. Epicenter files have been updated, with 548 earthquakes
located and over 3,500 detected.
UPDATE
(4/10 0930PDT): New Horizon is currently departing
Eureka,CA after a full night of preparation. Seas are reported
as calm. ETA at the target site is midnight. Seismicity
continues with over 3,000 events detected in six days.John
Nabelek at Oregon State University has posted earthquake
moment
tensor solutions for the larger earthquakes detected
by land arrays.
UPDATE
(4/9 1630PDT): New Horizon arrived in Eureka,
CA at 1430PDT and began loading scientific equipment. All
member of the scientific field party are on site and setting
up their instruments. High winds and rough seas may delay
departure to ensure that equipment has been properly secured.
Seismicity continues at a moderate level. Epicenter maps
and earthquake listings have been updated.
UPDATE
(4/9 0830PDT): Seismic activity continued over the weekend
at a moderate rate. Nearly 2,500 earthquakes have been detected
to date. The New Horizon is expected in to Eureka,
CA after 1500 PDT on Monday April 9. The scientific party
is in transit to Eureka to meet the ship.
UPDATE
(4/7 1400PDT): Seismic activity continues at 10-20 events
per hour. New Horizon being slowed by north winds
and strong currents and may be delayed arriving in Eureka.
UPDATE
(4/6 1130PDT): Seismic activity continues at a moderate
rate.Nearly 2,000 earthquakes have been detected in 2.5
days. Response cruise planning continues
UPDATE
(4/6 0800PDT): Activity continues at a reduced rate.
Response cruise planning continues.
UPDATE
(4/5 1030PDT): Response planning continues. The Scripps
RV New Horizon may be available in San Diego.
