GEOCYATHERM LEG 3

Name: GEOCYATHERM LEG 3
Start: 1982-02-12
End: 1982-02-28
Location: Northeast Pacific Ocean (180W)

Type	Oceanographic cruise
Ship	Le Suroît
Ship owner	Ifremer
Dates	12/02/1982 - 28/02/1982
Chief scientist(s)	HEKINIAN Roger
	GEO-OCEAN - UMR 6538 Univ. Brest, CNRS, Ifremer, Univ. Bretagne Sud Place Nicolas Copernic 29280 Plouzané https://www.geo-ocean.fr/
DOI	10.17600/82001713
Objective	The GEOCYATHERM cruise was part of CNEXO's programme to study ocean hydrothermalism. Its main objectives were: to discover active hydrothermal sites, to study them in situ (physical, chemical and geological studies) and to estimate the importance of sulphide fields in a specific area, and to explore the ridge (from the surface and submersible) to discover hydrothermal and volcanic (Seamount) sites outside the accretionary axes.

Sea/Ocean

Northeast Pacific Ocean (180W)

(PACIFIQUE NORD EST)

Ports

Port of departure : Acapulco (Mexico)

Port of return : Manzanillo (Mexico)

Scientific Authority

GÉOSCIENCES MARINES

Centre Ifremer Bretagne

ZI Pointe du Diable

29280 Plouzané

+33(0)2 98.22.42.24

Participating bodie(s)

IFREMER CENTRE DE BREST

Discipline(s)

SUBMERSIBLE
PHYSICAL OCEANOGRAPHY
MARINE GEOSCIENCES

Code	Label	Quantity	PI
D01	Current meters	7 deployments	MINSTER Jean-François
D90	Other physical oceanographic meas. Mesures isolees de T au fond	5 measurements	MINSTER Jean-François
G02	Grab	2 samples	HEKINIAN Roger
G04	Core soft bottom	2 cores	HEKINIAN Roger
G08	Bottom photography Avec RAIE	-	HEKINIAN Roger
G28	Magnetic measurements	-	HEKINIAN Roger
G74	Multi-beam echosounding Faisceau large	-	HEKINIAN Roger
G90	Other geosciences meas. Prelevements a partir d'engins sous-marins	20 samples	HEKINIAN Roger
H09	Water bottle stations	7 stations	MINSTER Jean-François
H71	Surface measurements underway (T,S) Enregistrement continu S (3) et T (3) en surface	6	MINSTER Jean-François
H72	Thermistor chain	1 deployments	HEKINIAN Roger
Y01	Underwater photography	-	HEKINIAN Roger

Summary of measurements

-Deployment of acoustic beacon fields on 4 zones.
-Recovery of a sediment trap.
-Mooring of 5 sediment traps (+ current meter).
-14 hydrology stations (+ current meter).
-4 ray stations.
-14 Shippeck grab stations.
-3 short corer stations.
-Mooring and recovery of a thermistor chain.
-32 CYANA dives (including 6 with fluid sampling).

Positionning system

Geodetic system : WORLD GEODETIC SYSTEM 1972 = WGS72

Positioning system : CYANA:acoustique

Sampling operations

Name	Dive	Equipement	Date	Location	Depth(m)
CY-82-21	521-21	Panier	19820215 00:00:0015/02/1982 00:00:00	12° 47.500' N 103° 57.000' W	-
CY-82-24	524-24	Panier	19820218 00:00:0018/02/1982 00:00:00	12° 50.600' N 103° 57.000' W	-
CY-82-25	525-25	Panier	19820219 00:00:0019/02/1982 00:00:00	12° 50.600' N 103° 57.000' W	-
CY-82-27	527-27	Panier	19820221 00:00:0021/02/1982 00:00:00	12° 44.800' N 103° 56.800' W	-
CY-82-30	530-30	Panier	19820224 00:00:0024/02/1982 00:00:00	12° 50.600' N 103° 57.000' W	-
CY-82-31	531-31	Panier	19820225 00:00:0025/02/1982 00:00:00	12° 47.000' N 103° 56.000' W	-
GCY-KS-01	-	Carottier boite REYNECK	19820221 03:14:0021/02/1982 03:14:00	12° 46.430' N 103° 58.820' W	2925
GCY-KS-02	-	Carottier boite REYNECK	19820224 00:14:0024/02/1982 00:14:00	12° 44.480' N 103° 58.330' W	2950
GCY-KS-03	-	Carottier boite REYNECK	19820224 02:30:0024/02/1982 02:30:00	12° 44.510' N 103° 58.430' W	2950
GCY-SH-07	-	Benne SHIPECK	19820215 04:30:0015/02/1982 04:30:00	12° 46.660' N 103° 57.680' W	2625
GCY-SH-08	-	Benne SHIPECK	19820217 02:59:0017/02/1982 02:59:00	12° 51.480' N 103° 55.780' W	2660
GCY-SH-09	-	Benne SHIPECK	19820218 03:03:0018/02/1982 03:03:00	12° 50.300' N 103° 55.750' W	2840
GCY-SH-10	-	Benne SHIPECK	19820219 03:08:0019/02/1982 03:08:00	12° 51.280' N 103° 59.010' W	2710
GCY-SH-11	-	Benne SHIPECK	19820222 03:26:0022/02/1982 03:26:00	12° 47.360' N 103° 54.080' W	2870
GCY-SH-12	-	Benne SHIPECK	19820226 03:15:0026/02/1982 03:15:00	12° 49.100' N 103° 57.310' W	-

Dives

Related number	Absolute number	Vehicle	Date	Location
21	521	Cyana	19820215 17:15:0015/02/1982 17:15:00	0° 0.000' N 0° 0.000' E
22	522	Cyana	19820216 17:36:0016/02/1982 17:36:00	0° 0.000' N 0° 0.000' E
23	523	Cyana	19820217 19:17:0017/02/1982 19:17:00	0° 0.000' N 0° 0.000' E
24	524	Cyana	19820218 16:44:0018/02/1982 16:44:00	0° 0.000' N 0° 0.000' E
25	525	Cyana	19820219 18:07:0019/02/1982 18:07:00	0° 0.000' N 0° 0.000' E
26	526	Cyana	19820220 16:40:0020/02/1982 16:40:00	0° 0.000' N 0° 0.000' E
27	527	Cyana	19820221 16:37:0021/02/1982 16:37:00	0° 0.000' N 0° 0.000' E
28	528	Cyana	19820222 16:14:0022/02/1982 16:14:00	0° 0.000' N 0° 0.000' E
29	529	Cyana	19820223 15:43:0023/02/1982 15:43:00	0° 0.000' N 0° 0.000' E
30	530	Cyana	19820224 16:22:0024/02/1982 16:22:00	0° 0.000' N 0° 0.000' E
31	531	Cyana	19820225 16:08:0025/02/1982 16:08:00	0° 0.000' N 0° 0.000' E
32	532	Cyana	19820226 16:31:0026/02/1982 16:31:00	0° 0.000' N 0° 0.000' E

Bibliography

Publications

Jean-Baptiste P, Fouquet Yves (1996). Abundance and isotopic composition of helium in hydrothermal sulfides from the East Pacific Rise at 13 degrees N. Geochimica Et Cosmochimica Acta, 60(1), 87-93. https://doi.org/10.1016/0016-7037(95)00357-6

Crane Kathleen, Aikman Frank, Foucher Jean-Paul (1988). The distribution of geothermal fields along the East Pacific Rise from 13°10′ N to 8°20′ N: Implications for deep seated origins. Marine Geophysical Researches, 9(3), 211-236. https://doi.org/10.1007/BF00309974

References of Articles published in other Periodicals or Scientific Works acclaimed in the Field

Vaslet Nathalie, Fouquet Yves, Voisset Michel, Bougault Henri (1989). Apports des images du sonar latéral SAR à la cartographie d'une zone hydrothermale de la ride Est Pacifique. Comptes Rendus De L Academie Des Sciences Serie Ii, 309(2), 267-273.

Bideau Daniel, Fouquet Yves, Hekinian Roger (1985). Découverte de basaltes métamorphisés dans le graben axial de la dorsale Est-Pacifique à 12°50' N. Bulletin De La Societe Geologique De France, 1(6), 905-913.

References of Technical Reports

Dyment Jérôme, Lallier François, Le Bris Nadine, Rouxel Olivier , Sarradin Pierre-Marie , Lamare Sylvain, Coumert Coralie, Morineaux Marie, Tourolle Julie (2014). Les impacts environnementaux de l’exploitation des ressources minérales marines profondes. Expertise scientifique collective. Rapport, CNRS – Ifremer, 937 p. https://archimer.ifremer.fr/doc/00872/98434/

CNEXO, COB, Brest (1982). Compte-rendu de campagne : CYATHERM.