Surveys

Survey operations in progress until further notice by M/V thalassa along trackline between 45-47.8N…

North Atlantic Ocean · HYDROLANT 2040/18

What this record establishes

Archived notice · 2018-06-24 16:25Z

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 271/18 231606Z JUN 18.. Issued 2018-06-23 16:14Z. 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
North Atlantic Ocean. The map shows the reported line or operation extent; it is not a vessel track. Check the original wording for limits and qualifications.

Related notices and cancellation links

Current notices and reporting history in the North Atlantic Ocean →

issued
2018-06-23 16:14Z
status
Archived notice
authority
NAVAREA II 271/18 231606Z JUN 18.
NAVAREA
NAVAREA II · named as the source of this relay
sea
North Atlantic Ocean
position
46.543, -19.677
vessel
M/V THALASSA · 139 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

EASTERN NORTH ATLANTIC.
DNC 08.
1. SURVEY OPERATIONS IN PROGRESS UNTIL FURTHER NOTICE
   BY M/V THALASSA ALONG TRACKLINE BETWEEN
   45-47.8N 019-05.5W AND 47-17.4N 020-15.8W.
   WIDE BERTH REQUESTED.
2. CANCEL HYDROLANT 2032/18.

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.
Until further notice
The operation or danger has no scheduled end; the warning stays in force until a later message cancels it.
Track line joining
Introduces a route through a series of positions — a cable route, a tow's track or a survey line.
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.
Cancellation reference
A line that cancels an earlier warning by its number, such as CANCEL HYDROLANT 1085/12.
HYDROLANT
The U.S. long-range warning series for Atlantic waters outside NAVAREA IV, including the eastern Atlantic, the Mediterranean and adjoining seas.

All warning terms →

Collected reports in this area · survey operations

5 within 180 nm since 2018 · 0 in the last 12 months · 0 listed in force now

18
20
21

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.

Month of issue in the collected archive

J
F
M
A
M
J
J
A
S
O
N
D

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

Worldwide in the collected sources

55 survey operations listed in force · see all

Record snapshot 2026-10-02 06:23Z; 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.