Helen's Reef
Helen 's Reef (English for: Helen Reef ) is a shoal ( submarine Aufragung ) two kilometers east-northeast of the island of Rockall rock. At low tide the reef is usually less than two meters (6 feet) below the water surface; in strong low water and / or strong waves a small, rounded rock is from Helen 's Reef in troughs sometimes visible. Otherwise, the shoal, which is at high water to about 3.60 meters (12 feet) below sea level, water is usually recognizable by crashing waves. Depending on water levels and weather conditions such waves can occur in a wide range up to 30 meters; only in calm weather and easterly winds they can be seen only in larger intervals.
The reef is part of the Rockall Plateau, a micro- continent west of the Hebrides. It is therefore not out of rocks that would be typical for oceanic crust, but from the material of the Earth's continental crust. Various rock samples from the reef show that it is an olivine gabbro, whose age has been dated to about 81 million years. In this case, however, the rock is very similar with younger gabbros from the Paleogene, as are present, for example, on the Isle of Skye or St. Kilda, so that the Cretaceous age has been questioned. However, further dating of a basalt from the Rosemary Bank ( Rockall Plateau ) again yielded a Late Cretaceous age (71 to 69 million years, or maybe even a little older), which is secured by biostratigraphically interlayered sediments in this case.
In the area of the shoal is a strong negative magnetic anomaly was found; it is probably caused by locally high concentrations of ferromagnetic minerals of the rock.
Hazard to navigation, and Naming
For the seafaring Helen 's Reef has formed a serious threat for centuries. It was repeated as "very dangerous" (1848 ) or as "probably the greatest threat " described all seafaring obstacles of the environment ( 1960).
The first known human "contact " possibly took place in 1686, when a ship was shipwrecked here or on the nearby Rockall; the survivors managed to escape to St. Kilda (Scotland).
It was named shoal 1824, when the brigantine Helen of Dundee ( according to other sources: Helen of Dundee) on April 19, 1824 under their captain Thomas Erskine on the way to Montreal (Canada) in haze drove to the previously unknown reef and leak suggested; Crew and passengers tried for 13 hours to save the Helen by pumping until she had to give up. After a dinghy when launching had been destroyed, only the 12 -man crew and a passenger were able to save two other boats and were of the Bark Flora (supposedly on the way from Gdansk to Liverpool) recovered under Captain Baker. 16 passengers - including 7 women and children - died.
According to some information possibly became in 1806 a ship under Captain Osborn from Workington ( Cumbria ) in the area of the reef, and escaped with difficulty; A report from 1825 suggests, however, that it is that ship to shoals in the southeast (not in the northeast ) has acted Rockall.
The Scottish Geographical Magazine suspected decades later, it was " not unlikely that at least some of the puzzling cases of lost well- equipped vessels, as they are reported each year from the Atlantic are, with these dangerous, invisible reefs [ including the Helen 's Reef ] in conjunction. " Despite the known dangers were neither Helen 's Reef has also provided the rocks near Rockall up to this point with beacons, bells or tons; Trinity House - the beacon management for England - informed on inquiry, it was never adopted, Rockall lies under the jurisdiction of ( jurisdiction ) of the English beacon administration.
On June 28, 1904, the Danish passenger ship Norge ran on Helen 's Reef and sank within 20 minutes. 625 passengers and crew were drowned, only 170 survived. This is the hitherto most severe shipwreck in the North Atlantic.
Rockall remained unlit until at least 1955; only towards 1973 a beacon was erected at Helen 's Reef.