EK60 Water Column Sonar Data Collected During OES0505 |
Oceanographic Survey of Cross Seamount and Control Sites (OES0505, EK60). The goal
of the cruise was to collect physical and biological oceanographic data at three distinct
environment in the lee of the Island of Hawaii: a relatively near-shore pelagic environment
off Keahole Point, Hawaii, at Finch Seamount (17° 38.070?N, longitude 157° 41.723?W)
with a 1052 m deep peak, and at Cross Seamount (18°43.285? N, longitude 158° 15.710?
W), with an approximately 400 m deep plateau. Data collected consisted of CTD casts,
trawl samples, and continuous monitoring of currents and biological acoustic backscatter.
CTD cats were conducted at predetermined stations. CTDs were equipped with oxygen
sensors and fluorometers and water was sampled at discrete depths during each cast
for chloropigments and nutrients measurements. Trawl operations were conducted at
predetermined stations using a Cobb trawl at depths of the shallow (nighttime) and
deep (day and nighttime) sound scattering layers. Currents were continuously monitored
using a RD Instruments Acoustic Doppler Current Profiler (ADCP) operating at 75 kHz
frequency. Biological backscatter were recorded using the EK60 echosounder system
(38 and 120 kHz) along predetermined transects. During the survey, a High-frequency
Acoustic Recording Package (HARP) was deployed for marine mammal observation. |
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