Day 1 – Longyearbyen

Hi all, a quick update on Arctic Ocean 2016 activities having now left solid ground. The large international scientific contingent landed this afternoon at around 15h on a flight from Oslo-Tromsø-Longyearbyen.

Day 1 (2100h)
Location: 78° 14.20’N and 015° 39.13’E
Speed: 0.0 kts
Air Temp: 5°C
Water: 6.5 °C
Choccie stash levels: 99.5%

Photo: View from the deck of Oden back towards Longyearbyen

The icebreaker is currently anchored a few hundred meters out from the docks which provides nice views back to the town. This also means I can tap into the last of the norwegian 4G network before anchors-up at 0800h tomorrow. Apparently it will take about 24 hours to reach the ice edge (aka the realm of the polar bears). This will be the toughest bit in terms of waves and potential sea-sickness as it is open water, but once we are in the ice it is mostly vibrations and a minor bit of rolling that can be expected. Between information meetings and another fire safety drill we also had a flying visit from the Sysellmannen (Governor) of Longyearbyen in a helicopter  and we will rendezvous with les canadiens over the next 24-48 hours too. We have been issued with personal “COBS” phones to which we can call anyone on the ship (or everyone if we press the wrong button). There is also an internal Wifi system and a server to which we can share files with others onboard and see key ship stats. Apparently there is a microwave datalink that will be set up between the two ships as well. At midnight (still the midnight sun this far north!) tomorrow we will also switch timezones to UTC for the remainder of the trip. Excellent food so far, and I have not frequented the onboard gym or two saunas as yet.

Photo: View from the bow looking up to the bridge. Blue containers are where we will be cutting and sampling the core.

We also have rather comfortable living quarters with 4 person shared bunk-style rooms. I am located in a room portside towards the bow of the ship. Work hours, for those not on shift work, will probably revolve around meal times which are strictly set and include three square meals and two “Fika” or coffee breaks. Not one to differ from their Norwegian neighbours, the Swedes also prefer a rather early, ahem 1730h, dinner time.

That is all for now – my Twitter @ShepGracie might have more activity now that I see how the email is set up. Goodbye internet and hello Arctic Ocean.

Photo: From within the engine room. Can’t imagine how loud it will be when we are out in the ice!

08 August 2016, Longyearbyen

Arctic Ocean 2016 Sites of interest

This is the second Arctic Ocean blog (following the Overview post) and explains a little more about where we are heading and the type of features we are targeting. 

The seafloor, with its underlying sediments and rocks, is not as boring as it may seem. The Arctic Ocean may be the world’s smallest ocean but by no means does that translate to a simple evolutionary history – it is commonly said that we understand more about the surface of Mars than we do about our ocean floors. The Arctic Ocean is surrounded by shallow and largely flat continental shelves, and has a deep and undulating interior. It is in this central area where many aspects of geology and oceanography become particularly exciting, and where we are heading on Oden.

Figure: Overview of the Arctic Ocean topography and bathymetry (IBCAO) with major features labelled: AB Amundsen Basin, CP Chukchi Plateau, MJ Morris Jesup Rise, MS Marvin Spur, NB Nansen Basin, YP Yermak Plateau. The Lomonosov Ridge separates the two major basins of different ages and red box shows the general area of the cruise sampling sites.

The Arctic Ocean today is the culmination of a long history of horizontal and vertical plate motions; there have been plate collisions leading to mountain building events and/or subduction events where some rocks are pushed deep into the mantle, rifting between plates and the opening of new ocean basins, changes in sea-level, periods of glacial or greenhouse conditions as well as volcanism on massive and localized scales. The dynamic and intrinsic interplay between the geosphere, biosphere, atmosphere and hydrosphere is particularly pertinent in understanding the evolution of the Arctic. The sedimentary record (or “stratigraphic record”) can tell us a lot about the many geologic and oceanographic processes that have occurred within the Arctic – at least as far back in time as we can retrieve from the samples.

Figure: International chronostratigraphic chart (time, basically) which shows the names of the time periods we refer to, as well as their absolute ages – geoscientists often switch between names and numerical ages. On this cruise we will be looking at sediments from the first column, especially the last Quaternary period and hopefully the Cretaceous. Figure from the ICS webpage.

The Arctic Ocean consists of two major ocean basins; the Eurasia Basin in the eastern domain and the Amerasia Basin in the western domain. The long, thin Lomonosov Ridge separates the two basins which are of significantly different age. The opening of the long, linear Eurasia Basin is relatively well understood – spreading occurred around 55 million years ago (‘Ma’ or ‘Myrs ago’) along the Gakkel mid-oceanic ridge and is continuing today at a very slow rate of around 1 cm/yr. By contrast, the Amerasia Basin is thought to have opened over 100 million years ago and the style and timing of opening is hotly debated in the geoscience community. Part of this complication is related to several large bathymetric features of uncertain origins – some features are thought to include continental rocks, others oceanic rocks, and others a kind of transitional type or related to massive volcanism. In addition to physical sampling including coring, dredging and heatflow measurements, other methods to investigate the sub-surface structure of the region include gravity and magnetic measurements, as well as seismic waves and acoustic sound data.

GIF below: Simplified plate reconstruction (fixed Eurasia for reference) running from 160 million years ago to present-day showing the rotation and opening of the Amerasia Basin between 160-120 Ma followed by the Eurasia Basin from 55-0 Ma. You can also see some rifting and spreading between Greenland and North America and Greenland and Eurasia. Present-day topography is reconstructed and plate boundaries are in black. Base reconstruction is from Shephard et al. (2013; Earth Sci Reviews) and is visualized in the freely available software GPlates.

Below I summarize a few key structural features from the central Arctic relevant for the cruise. These features have variable rock types and ages as well as different thicknesses and ages of the overlying sediments. Generally speaking, some of the sediments are nice and flat, capturing a near continuous record of time, and are referred to as “conformable.” Other sites may have been disturbed by ice, water currents, have slumped down from a slope or been uplifted and exposed to sub-aerial erosion, and/or have been disturbed by tectonic motions through time.  On the cruise we aim to sample sediments of all ages from within the basin, and I am particularly interested in as old as possible.

Lomonosov Ridge: Slither of continental rock that rifted from the edge of Eurasia (e.g. the Barents Shelf) with the opening of the Eurasia Basin around 55 Myrs ago. There have been a number of expeditions to sample this feature including sedimentary coring samples and the only deep sea-drilling core ACEX. Both Russia and Denmark (Canada is yet to resubmit…) have submitted claims under UNCLOS covering parts of this ridge.

Alpha-Mendeleev Ridge: An extensive feature that broadly stretches from north of the Canadian Arctic Islands to the Russian shelf. Proposed to be part of the High Arctic Large Igneous Province that erupted around 120-90 Myrs ago. Whether the Alpha and/or the Mendeleev Ridge(s) includes, or is underlain by, continental or oceanic rocks is unclear – it is a key feature in understanding the opening of the Amerasia Basin. This is a site where we hope to recover some of the “older” sediments i.e. Cretaceous age ~ older than 66 Myrs. In particular we will re-visit some sites from the 1960-80’s T3 and CESAR expeditions.

Marvin Spur: This looks like a mini-me of the Lomonosov Ridge and might include some undisturbed sediments of Quaternary age. It is likely related to the same rifting event that opened the Eurasia Basin, even though it is located on the Amerasia Basin side of the larger Ridge.

Figure (right): Figures reproduced from Kristoffersen et al. (2007; Marine Geology) showing zoom into Lomonosov Ridge (top), sample of acoustic stratigraphy (middle; from AWI-91091) and interpretation of sediment type (bottom).

Canada Basin: Restricted region of the larger Amerasia Basin. Recent studies suggest that this is the only region of “true” oceanic seafloor. Prevailing models favour a counter-clockwise rotation of Alaska and parts of Russia away from Canada sometime around 140-100 Myrs ago. While we will not be sampling this area, considering the relationship between the Canada Basin and the remainder of the Amerasia Basin (especially the Alpha Ridge and the closest side of the Lomonosov Ridge) is critical for creating holistic regional models.

05 August 2016, Oslo

References:
–Kristoffersen, Y., Coakley, B., Hall, J.K., and Edwards, M. 2007. Mass wasting on the submarine Lomonosov Ridge, central Arctic Ocean. Marine Geology v.243 p.137-142.
–Shephard, G.E., Müller, R.D., Seton, M. 2013 The tectonic evolution of the Arctic since Pangea breakup: Integrating constraints from surface geology and geophysics with mantle structure. Earth-Science Reviews 124, 148-183

What’s in a name – Arctic Koala

While thinking of the blog name ‘Arctic Koala’ I was struck by a nice little bit of coincidence and thought to share it with you.

Arctic: Choice was easy given my current research interests, upcoming expedition destination and general predisposition the exoticness and remoteness of it all. Arctic derives from ἄρκτος or “arktos” meaning “bear” in Greek. Unlike its furry counterparts, this in reference to one or both the constellations that are visible in the Northern Hemisphere; Ursa Major aka the ‘Great Bear,’ or the Ursa Minor aka the ‘Little Bear.’ The reference to bears is thought to come from a mythological story regarding Zeus. In an additional twist, Ursa Minor is Latin for ‘Smaller She-Bear.’ The Little Bear contains Polaris, the North Star (also referred to as the Polar Star), which is close to the north celestial pole. It follows that Antarctic is the “anti” to the Arctic.

Photo: Koala at the Australian Wildlife Park north of Sydney.

Koala: Well, I love koalas, everybody loves koalas. They are one of Australia’s most iconic and seemingly cuddly (and yet have your heard them scream/growl? or seen their claws?) animals and happen to look like mini bears, kinda. While they are not technically bears and are the only extant member of their Family, let’s not let facts in the way of a good symbolic moment. The scientific name for them is Phascolarctos cinereus – and you will notice the “arctos” component, as above, and Phaskolos meaning “pouch.” While we are on the topic of etymology – “Koala” derives from the Indigenous Australian Dharug word gula. 

So indeed there is a little she-bear component in the Arctic….and I think that a Koala, albeit from the southern hemisphere, is as good a representative of a little bear as any. I also found an independent blog post drawing parallels between the koala and the ‘Great’ polar bear (Ursus maritimus) in terms of fur insulation, you can read that one here.

And there you have it, Arktos (Phascol)Arctos!

04 August 2016, Oslo

Arctic Ocean 2016 Objectives

Why am I off to the North Pole, you ask? Isn’t Norway far enough from Australia? This first blog post is a summary of some of the overarching objectives and themes for the expedition.

For the 43 days following this coming Monday, the 8th August, I will be onboard the Swedish Icebreaker Oden – for science! I am part of a ~60-strong team onboard Oden, including scientists and crew. We will be departing and returning to Longyearbyen, which is the main settlement on Svalbard, the largest island in the archipelago of Spitsbergen. Located at 78.2°N, we will indeed already be in the Arctic before we set sail!

Photo: View over Longyearbyen township looking towards the east, during my first visit to Svalbard in August 2015.

We are heading north towards the region of the Amundsen Basin and northern Amerasia Basin in order to target a number of bathymetric features, both by direct and indirect sampling methods. Below is a map of the general region to where we will be travelling. I am one of nine early career scientists invited by the Swedish Polar Research Secretariat, and am working within a sedimentary coring team which will work closely with a geophysical mapping group. This area is one of the most remote regions on the planet and holds many clues as to the geological evolution of the wider Arctic, as well the Arctic Ocean’s place within the global ocean network. There are several other scientific projects running in parallel (its not just rock and mud-loving geologists!) and I will follow up with another post on those soon. You will see that we are working in water depths in excess of 3000 m and in a region with bumpy seafloor terrane, which presents multiple technical challenges. Longyearbyen is located ~1,310 km from the North Pole which is comparable to the distance between Melbourne and Brisbane – probably won’t see any arctic kangaroos on this route though.

Figure (below): General Arctic Ocean 2016 expedition area and
Longyearbyen marked with star (IBCAO grid).

This polar expedition is a collaboration between the Swedish Polar Research Secretariat and the Canadian Government (via the Canadian Hydrographic Service, Natural Resources Canada and the Canadian Coast Guard). The overarching Canadian aim is related to their submission to Commission on the Limits of the Continental Shelf, which is part of the UN Convention on the Law of the Sea (UNCLOS). A submission goes through a lengthy review process, including considerations of neighbouring states’ claims – the conclusion of which may effectively extend a state’s jurisdiction over the continental shelf. The lead scientist (onboard Louis S. St-Laurent) is Mary-Lynn Dickson from Natural Resources Canada and the co-lead Scientist onboard Oden is Katarina Gårdfeldt from Chalmers University of Technology, Sweden. The official cruise blog and “Arctic Portal” along with further info can be found here.

The expedition will involve two icebreakers, Oden and its Canadian counterpart Louis S. St-Laurent, with data acquisition occuring on both of them.

Oden (call sign SMLQ):

•  Built in 1988
• Length of 107.8 m and beam (width) of 31.2 m (more tech specs).
• It can travel at around
  • 16.0 knots max (29.6 km/h; 18.4 mph) in open water
  • 3 knots (5.6 km/h; 3.5 mph) in 1.9 m of ice
• 24 500 horsepower

The Louis S. St-Laurent (call sign CGBN) is slightly older (built in 1966) as well as longer and thinner, at 119.8m by 24.38m (more tech specs). The ships will meet along route somewhere and there will be a helicopter on each ship. Being my first time onboard an icebreaker (excluding the often boozy pre-conference events that share the same name), and my first fieldwork trip in several years, witnessing the various ship operations and real-time data collection will certainly be an eye-opener. I apologize for any technical, or otherwise, inaccuracies in advance. This website has been useful for tracking the realtime locations of the ships but I am unsure how far north it will be able to track given the limited satellite coverage.

What is not shown in the topography and bathymetry map above is the ice coverage – and of course, that is the reason why you need an impressive ice-breaking vessel to travel to the North Pole. One of the reasons this part of the Arctic Ocean is so poorly understood is because it has some of the thickest and most persistent ice coverage, even in the aftermath of summer. Below is a map from this website which shows some the latest sea ice thickness and coverage as of the 2nd August 2016. You will see that there are regions of ice >4 m in thickness – this will be a factor determining the eventual ship track and sampling locations.

Figure: The large map shows the sea ice thickness in the Northern Hemisphere. Inset shows the yearly variation of the sea ice volume in the Northern Hemisphere. Updated daily and used from http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent/#tabs-1

Undertaking fieldwork is usually very expensive, let alone conducting it from within the central Arctic Ocean, and therefore being able to participate in such an exciting research expedition is wholly dependent on securing funding and/or scholarships. I would like to end this post by thanking the Swedish Polar Research Secretariat for the opportunity and the initiative shown towards early career scientists.

03 August 2016, Oslo