Cruise inventory

RRS James Clark Ross JR19990425 (AMT8, JR41, JR42)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Clark Ross (74JC)
Cruise identifierJR19990425 (AMT8, JR41, JR42)
Cruise period1999-04-25 — 1999-06-07
StatusCompleted
Port of departureStanley, Falkland Islands (Malvinas)
Port of returnGrimsby, United Kingdom
PurposeResearch
ObjectivesAMT 8: This cruise took place in two legs, April 25th - April 29th and May 18th -June 7th 1999. The Principal Scientist was Nigel Rees from PML. The AMT 8 cruise report is only available electronically and is an incomplete document (http://web.pml.ac.uk/amt/cruises/AMT8/amt8.html). There are no plans to produce a finished document.

JR42: The structure of the Earth's crust at oceanic volcanic islands is of interest for the information it provides both about the processes involved in the formation of these islands and about the rheology of the underlying oceanic lithosphere, which deforms in response to the island load. Since some of the acoustic energy from large underwater explosions is commonly coupled into the oceanic sound channel as so-called "T-phases", hydrophones around several such islands and broadband seismic stations on the islands are being used for monitoring of the Comprehensive Test Ban Treaty. Cruise JR42 involved a four-day seismic experiment around the island of Ascension, a 4-km-high volcano some 90 km west of the Mid-Atlantic Ridge. During the experiment, a 6186 cu. in. airgun array was fired at one-minute intervals for about two days along a series of lines extending up to 45 km from the coast of the island. These shots were received by hydrophones and sonobuoys offshore and seismometers onshore. The shots were used to locate and calibrate three permanently installed hydrophones, to study the coupling of seismic energy into the island slope, and to study the structure of the crust beneath the island. The experiment was funded by the US Department of Energy (through Lawrence Livermore National Laboratory (LLNL)), the US Office of Naval Research, the UK Natural Environment Research Council, the United Nations (through the Comprehensive Test Ban Treaty Office in Vienna), IFREMER's Centre de Brest, and funds held at the University of Southampton by T. A. Minshull.
Chief scientistNigel Rees (Plymouth Marine Laboratory), Tim A Minshull (University of Southampton School of Ocean and Earth Science)
ProjectAtlantic Meridional Transect (AMT)
Coordinating bodyNatural Environment Research Council (NERC)
Cruise reportRRS James Clark Ross JR19990425 (AMT8, JR41, JR42) cruise report jr41.pdf — access key 'C' (0.57 MB)  RRS James Clark Ross JR19990425 (AMT8, JR41, JR42) cruise report jr42.pdf (0.31 MB) 
Ocean/sea areas 
GeneralNorth Atlantic Ocean
South Atlantic Ocean
Track chartsRRS James Clark Ross JR19990425 (AMT8, JR41, JR42) cruise track — jr42trk.pdf (0.06 MB) 
Data held at BODC 
Series/Profiles 
38  CTD/STD cast
Visible waveband radiance and irradiance measurements in the water column
Density of the water column
Transmittance and attenuance of the water column
Chlorophyll pigment concentrations in water bodies
Raw fluorometer output
Vertical spatial coordinates
Salinity of the water column
Temperature of the water column
Visible waveband radiance and irradiance measurements in the water column
Density of the water column
Transmittance and attenuance of the water column
Chlorophyll pigment concentrations in water bodies
Raw fluorometer output
Vertical spatial coordinates
Salinity of the water column
Temperature of the water column

BODC idDate/TimeLocationDoc.
10732141999-04-25 18:05 47° 36' 43" S  53° 57' 9" W  View metadata report for BODC series reference number 1073214
10732261999-04-26 00:46 46° 30' 4" S  52° 59' 46" W  View metadata report for BODC series reference number 1073226
10732381999-04-26 16:42 43° 30' 37" S  52° 59' 24" W  View metadata report for BODC series reference number 1073238
10732511999-04-26 23:14 42° 29' 55" S  53° 0' 0" W  View metadata report for BODC series reference number 1073251
10732631999-04-27 10:00 41° 11' 48" S  53° 0' 13" W  View metadata report for BODC series reference number 1073263
10732751999-04-27 15:37 40° 11' 56" S  53° 0' 8" W  View metadata report for BODC series reference number 1073275
10732871999-04-27 22:49 39° 0' 16" S  52° 59' 41" W  View metadata report for BODC series reference number 1073287
10732991999-04-28 10:05 38° 0' 27" S  52° 59' 44" W  View metadata report for BODC series reference number 1073299
10733061999-05-03 14:12 35° 5' 1" S  51° 40' 20" W  View metadata report for BODC series reference number 1073306
10733181999-05-05 17:09 30° 43' 44" S  42° 17' 8" W  View metadata report for BODC series reference number 1073318
10733311999-05-06 14:01 28° 51' 3" S  38° 19' 8" W  View metadata report for BODC series reference number 1073331
10733431999-05-07 13:04 26° 53' 44" S  34° 15' 5" W  View metadata report for BODC series reference number 1073343
10733551999-05-08 14:51 24° 33' 16" S  29° 33' 44" W  View metadata report for BODC series reference number 1073355
10733671999-05-09 13:50 22° 13' 43" S  25° 49' 1" W  View metadata report for BODC series reference number 1073367
10733791999-05-10 11:31 19° 12' 37" S  23° 13' 14" W  View metadata report for BODC series reference number 1073379
10733801999-05-10 14:04 18° 59' 25" S  23° 2' 44" W  View metadata report for BODC series reference number 1073380
10733921999-05-12 10:33 13° 10' 9" S  18° 7' 34" W  View metadata report for BODC series reference number 1073392
10734111999-05-13 10:33 9° 51' 33" S  15° 24' 7" W  View metadata report for BODC series reference number 1073411
10734231999-05-18 13:43 7° 37' 59" S  14° 29' 51" W  View metadata report for BODC series reference number 1073423
10734351999-05-20 10:38 0° 4' 27" S  16° 42' 36" W  View metadata report for BODC series reference number 1073435
10734471999-05-21 10:33 3° 53' 58" N  17° 52' 59" W  View metadata report for BODC series reference number 1073447
10734591999-05-22 10:34 7° 37' 14" N  18° 59' 15" W  View metadata report for BODC series reference number 1073459
10734601999-05-23 10:34 11° 33' 51" N  20° 8' 53" W  View metadata report for BODC series reference number 1073460
10734721999-05-24 10:42 15° 9' 0" N  20° 59' 55" W  View metadata report for BODC series reference number 1073472
10734841999-05-25 10:38 18° 48' 8" N  20° 59' 57" W  View metadata report for BODC series reference number 1073484
10734961999-05-26 10:37 22° 54' 41" N  21° 0' 25" W  View metadata report for BODC series reference number 1073496
10735031999-05-28 10:32 30° 28' 37" N  21° 33' 38" W  View metadata report for BODC series reference number 1073503
10735151999-05-29 10:33 34° 21' 56" N  20° 47' 15" W  View metadata report for BODC series reference number 1073515
10735271999-05-30 10:34 38° 10' 37" N  20° 0' 54" W  View metadata report for BODC series reference number 1073527
10735391999-05-31 10:36 42° 0' 7" N  20° 0' 0" W  View metadata report for BODC series reference number 1073539
10735401999-06-01 10:10 45° 56' 37" N  19° 58' 42" W  View metadata report for BODC series reference number 1073540
10735521999-06-01 18:01 46° 59' 59" N  19° 59' 48" W  View metadata report for BODC series reference number 1073552
10735641999-06-02 10:36 47° 27' 16" N  15° 39' 52" W  View metadata report for BODC series reference number 1073564
10735761999-06-03 10:42 48° 8' 55" N  9° 39' 52" W  View metadata report for BODC series reference number 1073576
10735881999-06-03 15:07 48° 15' 17" N  9° 14' 14" W  View metadata report for BODC series reference number 1073588
10736071999-06-04 10:45 48° 58' 39" N  9° 15' 0" W  View metadata report for BODC series reference number 1073607
10736191999-06-04 13:04 48° 58' 59" N  9° 11' 1" W  View metadata report for BODC series reference number 1073619
10736201999-06-05 09:42 49° 41' 54" N  4° 26' 26" W  View metadata report for BODC series reference number 1073620
1  Meteorological data logger
Air pressure
Wind strength and direction
Horizontal spatial co-ordinates
Date and time
Air pressure
Wind strength and direction
Horizontal spatial co-ordinates
Date and time

BODC idDate/TimeLocationDoc.
12229961999-04-24 18:25:01  — 1999-06-07 08:02:01 51° 41' 30" S  57° 49' 19" W — 53° 30' 6" N  0° 25' 48" E  View metadata report for BODC series reference number 1222996
1  Multiple instrument types
Chlorophyll pigment concentrations in water bodies
Raw fluorometer output
Salinity of the water column
Horizontal spatial co-ordinates
Temperature of the water column
Date and time
Chlorophyll pigment concentrations in water bodies
Raw fluorometer output
Salinity of the water column
Horizontal spatial co-ordinates
Temperature of the water column
Date and time

BODC idDate/TimeLocationDoc.
12230111999-04-24 18:25:01  — 1999-06-07 08:02:01 51° 41' 30" S  57° 49' 19" W — 53° 30' 6" N  0° 25' 48" E  View metadata report for BODC series reference number 1223011
1  Single-beam echosounder
Bathymetry and Elevation
Horizontal spatial co-ordinates
Date and time
Bathymetry and Elevation
Horizontal spatial co-ordinates
Date and time

BODC idDate/TimeLocationDoc.
12229841999-04-24 18:25:01  — 1999-06-07 08:02:01 51° 41' 30" S  57° 49' 19" W — 53° 30' 6" N  0° 25' 48" E  View metadata report for BODC series reference number 1222984
Discrete samples 
38  CTD frame plus rosette samplerTransmittance and attenuance of the water column
Density of the water column
Visible waveband radiance and irradiance measurements in the water column
Chlorophyll pigment concentrations in water bodies
Raw fluorometer output
Salinity of the water column
Temperature of the water column
Carotenoid and flavenoid pigment concentrations in water bodies
Raw light meter output
108  Expendable BathythermographTemperature of the water column
324  Sample taken from ship's non-toxic supplyChlorophyll pigment concentrations in water bodies
Carotenoid and flavenoid pigment concentrations in water bodies