RRS James Clark Ross JR19990115 (JR39a)
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS James Clark Ross (74JC) |
| Cruise identifier | JR19990115 (JR39a) |
| Cruise period | 1999-01-15 — 1999-02-09 |
| Status | Completed |
| Port of departure | Stanley, Falkland Islands (Malvinas) |
| Port of return | Stanley, Falkland Islands (Malvinas) |
| Purpose | Research |
| Objectives | The very first scientific cruise of the James Clark Ross (JR01) acquired data along tracks in the northern Weddell Sea, designed to follow gravity ridges as far as 63°S (a second cruise, JR07, had been planned to undertake this work in areas further south but was cancelled). Two sections of the record, in particular, were of interest. The first was an apparent disruption of the spreading pattern, referred to informally as the 'kink', and the second was the abrupt termination of the ridge-trough pattern near 69°S, known as 'Anomaly-T'. Understanding the nature and significance of these features form the prime objectives for JR39a. |
| Chief scientist | Roy Livermore (British Antarctic Survey) |
| Cruise report |  (7.37 MB) |
| Ocean/sea areas | |
| General | South Atlantic Ocean |
| Specific | Weddell Sea, South Sandwich Is. |
| Measurements | |
| Geology and geophysics | |
| Single channel seismic reflection | Quantity: number of surveys = 1 Description: A profile was made across the extinct axis of the West Scotia Ridge. |
| Single channel seismic reflection | Quantity: number of profiles = 4 Description: A number of seismic profiles were made during the cruise. The profiles showed the basement structure. |
| Magnetic measurements | Quantity: number of profiles = 1 Description: Magnetic profiles were made on both outward and return legs of the cruise. |
