Survey operations 210001Z jul to 010100Z oct by M/V prospector towing 12 four mile long cables in area bound…
Gulf of Guinea · HYDROLANT 1634/23
What this record establishes
Archived notice · 2023-09-03 23:26Z
This notice comes from the historical archive. Its archived status does not establish when or how the reported situation ended.
- Source and dates
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · NAVAREA II 193/23 200904Z JUL 23.. Issued 2023-07-20 09:46Z. First collected 2026-08-17 13:38Z; last seen in collection 2026-08-17 15:46Z. Collection dates record ingestion, not a new incident or a fresh field observation.
- Location covered
- Gulf of Guinea. The map shows an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.
Related notices and cancellation links
- Cancel HYDROLANT 1592/23, 1634/23 and this msglater cancellation notice
Current notices and reporting history in the Gulf of Guinea →
Activity windows · 1 in this warning
| opens (UTC) | closes (UTC) | local | length |
|---|---|---|---|
| 2023-07-21 00:01Z | 2023-10-01 01:00Z | — | 1728 h 59 |
Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.
- issued
- 2023-07-20 09:46Z
- status
- Archived notice
- self-cancels
- 2023-10-02 00:01Z
- authority
- NAVAREA II 193/23 200904Z JUL 23.
- NAVAREA
- NAVAREA II · named as the source of this relay
- sea
- Gulf of Guinea
- position
- 3.499, 7.471
- vessel
- M/V PROSPECTOR · 2 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
GULF OF GUINEA. EQUATORIAL GUINEA. DNC 01. 1. SURVEY OPERATIONS 210001Z JUL TO 010100Z OCT BY M/V PROSPECTOR TOWING 12 FOUR MILE LONG CABLES IN AREA BOUND BY 03-55.41N 007-47.29E, 03-45.72N 007-56.25E, 03-04.26N 007-09.38E, 03-15.00N 007-00.72E. SIX MILE BERTH REQUESTED. 2. CANCEL THIS MSG 020001Z OCT 23.
Reading this warning
- DNC (Digital Nautical Chart)
- A reference to one of the regions of NGA's Digital Nautical Chart, used to tell the reader which charts a warning affects.
- Survey operations
- A research or survey vessel is mapping the seabed or water column, often while towing equipment.
- Date-time group (DTG)
- A compact UTC timestamp — day, hour and minute followed by Z — such as 201500Z for the 20th at 15:00 UTC.
- Towed array / streamer
- Equipment towed a long way behind a vessel — sonar, a hydrophone cable, a sampling sled — invisible at the surface.
- Tow / towing
- A vessel towing another vessel, a barge or a structure — slow, hard to manoeuvre, and with a long line between.
- Area bound by
- Introduces a list of positions that are the corners of an area — the polygon the warning applies to.
- Position (degrees and minutes)
- How warnings write positions: degrees, a hyphen, then minutes, with N/S and E/W — 49-40.8N 003-43.8W.
- Wide berth requested
- Keep well clear — or, when a distance is given ("TWO MILE BERTH REQUESTED"), at least that far away.
- CANCEL THIS MSG
- The warning's own expiry: a line telling the reader when the message cancels itself.
Collected reports in this area · survey operations
36 within 180 nm since 2003 · 2 in the last 12 months · 1 listed in force now
Counts include repeat notices about the same situation. NGA archive coverage ends 2024-05; live collection began 2026-08-17. The period between them is incomplete. An empty year is not evidence that no hazards occurred.
- Last known positions of mobile oil rigs and drill ships at 040430 UTC sep 262026-09-04
- Last known positions of mobile oil rigs and drill ships at 091630 UTC aug 262026-08-09
- Survey operations in progress until 22 apr by M/V borda in area bound by 03-44.80N 009-21.70E, 03-52.20N…2024-04-14
- Survey operations in progress until 09 apr by M/V borda in area bound by 03-44.8N 009-21.7E, 03-52.2N…2024-04-03
- Survey operations 27 mar thru 15 may by M/V rem saltire and M/V bgp dragon in area bound by 03-06.80N…2024-03-24
- Survey operations 12 feb thru 26 mar by M/V bgp dragon and M/V rem saltire in area bound by 03-17.54N…2024-02-09
Month of issue in the collected archive
All available years combined. Uneven collection and repeat bulletins affect these counts; this chart does not measure the seasonality or probability of incidents.
Nearby notices listed in force · within 120 nm
- Aids to navigationNav aids · 35 nm
- Newly discovered dangersWrecks · 55.1 nm
- Dangerous wreck in 04-18.50N 007-02.20EWrecks · 55.1 nm
Worldwide in the collected sources
56 survey operations listed in force · see all
Record snapshot 2026-10-01 19:53Z; source collection times vary.
Surveys
Hydrographic and scientific survey vessels, often towing long arrays. All current survey operations →
Not for navigation. This is a re-rendering of an official navigational warning for awareness; mariners must use official NAVAREA broadcasts and their national MSI service.