Searching more in deeper water

24.06.2016
Acquisition of geological samples and deepsea minerals from the Norwegian Sea will continue this summer in order to boost understanding of resources and geological developments in the North Atlantic.

| Nils Rune Sandstå

Locations of underwater bedrock sampling by the NPD

Locations of underwater bedrock sampling by the NPD. Yellow stars indicate sites on the Jan Mayen Ridge where samples were taken by grab in 2011 and chainsaw the following year. Shallow wells drilled in 2014 are indicated by the blue star. White stars show where samples were taken on the Gjallar Ridge and the Vøring Spur in 2013. Materials will also be acquired there this year.

 

Funds have been allocated by the NPD for the collection of seabed samples from the Vøring Spur by the University of Bergen (UiB), a project which builds on a collaboration under way since 2010.

Bathymetric data on subsea terrain acquired for the NPD around Jan Mayen in 2010 provided the basis for collecting seabed material with a remotely operated vehicle (ROV) in 2011 and 2012.

Several successful ROV dives were subsequently carried out in 2013 on Gjallar Ridge South and the Vøring Spur in the Norwegian Sea. This work included acquiring material in 3 600 metres of water in the second of these areas.

In 2014, the NPD acquired shallow cores from the outer parts of the Møre Basin. The map above shows the areas which have been explored as well as those due to be examined further.

 

Identify

All this sampling forms part of efforts to identify reservoir rocks on the Jan Mayen Ridge and the outer NCS in the Norwegian Sea.

Norway, Jan Mayen and Greenland were previously joined as part of a single continent, which split apart about 60 million years ago when the North Atlantic began to open up.
As a result, reservoir rocks on the Jan Mayen Ridge and Norway’s outer continental shelf are likely to be similar to those found on land in Greenland.

But the fracturing process itself was complicated, so that determining in detail how Greenland, the Jan Mayen Ridge and the NCS once fitted together is a bit of a jigsaw puzzle.

Samples are therefore being acquired to secure data points which can help solve this conundrum and support the search for the types of reservoir rocks seen in Greenland.

Moreover, the samples acquired have been very important for learning more about metallic seabed minerals on the NCS, and the NPD will follow up this aspect in its continuing investigations.

In addition to straightforward chunks of rock, samples of manganese crust were acquired on both the Jan Mayen Ridge and the Vøring Spur.

 

Metallic minerals

Representing a coating of metallic minerals precipitated from seawater onto exposed seabed rocks, such crusts consist mainly of manganese and iron.

But other and far more valuable metals are also present. These include cobalt, nickel, titanium, platinum, scandium (used in aluminium alloys, for example) and rare soil types.
With their metal content varying around the world, deposits of this kind are currently attracting considerable international interest.

The image below shows one of the NPD's sampling locations on the Vøring Spur, where a manganese crust has grown on the sheer rock face.

The UiB is in the process of completing a detailed geochemical study of NPD crust samples from the Jan Mayen Ridge to identify which metals could be interesting resources in this area. Further studies of such manganese crusts are due to be carried out by the NPD and the UiB.

 

The site showing manganese crust on the Vøring Spur where samples were acquired in 2013.

The site showing manganese crust on the Vøring Spur where samples were acquired in 2013.

 

Bathymetric data have also been made available by the NPD for studies of the Mohns Ridge, a mid-oceanic spreading ridge which extends from Jan Mayen to Bear Island.
Such underwater features are volcanic and produce metallic sulphide minerals through hydrothermal vents known as "black smokers".

These deposits are again the focus of worldwide financial interest today. The most interesting metals in this context are copper, lead, zinc, gold and silver.

The UiB has conducted scientific investigations to identify the geological and biological processes at work in the volcanic systems on the Mohns Ridge.

 

Knowledge

These studies also form the basis for current knowledge of the metal resources located there. Research and acquisition missions by the UiB and the NPD have largely been mobilised on a joint basis throughout the Norwegian Sea.

Moreover, the Norwegian University of Science and Technology (NTNU) is due to conduct its first mission to examine sulphide minerals on the Mohns Ridge this year.

Based on the NPD’s bathymetric data and the long-running UiB surveys, funding for this work comes largely from the Research Council of Norway.

The NPD will continue to investigate the Vøring Spur during the UiB mission this summer. Previous experience suggests that basalt, thick manganese crusts and straightforward sediments will be found.

Metallic components contained in manganese crusts could become an important deepsea resource. This year’s sampling will give the NPD a better foundation for continued mapping of the scope, quality and size of such deposits.


Topics: Geology