Drilling under the northern lights

The steep learning curve associated with swapping exploration in the Western Australian outback for interior Alaska

by Ashleigh Ball

Exploration in Alaska is a remote, challenging and often an expensive endeavor. In a place where untested veins still outcrop at surface and huge swathes of underexplored to completely unexplored ground still exists the rewards can be high.

In 2020, I was given the opportunity to swap exploration in Western Australia’s Goldfields for exploration in interior Alaska. I encountered immediate differences. The obvious ones were a mountainous landscape, the need for helicopters, hazardous wildlife and extreme weather. But there were also the less obvious ones that took time to understand such as subtle differences in culture, recruitment challenges and collecting and working with data in mountainous terrain.

I had visions of summer field campaigns involving hiking from ridge to ridge under the midnight sun, measuring quartz veins with towering mountains in the background. While some of this turned out to be true, many of my preconceived ideas also turned out to be completely wrong. I quickly realized that exploration in interior Alaska could be very challenging, both physically and technically, and that exploring in the outback was like a walk in the park compared to this. The following are some of the biggest myths that were busted during my time in Alaska: The first myth: there are mountains, therefore there will be good outcrop.

Compared to outback Australia where there is commonly less than 2% outcrop to none at all, I was under the illusion that the mountainous Alaskan terrain would mean excellent outcrop. I had romantic visions of hiking from outcrop to outcrop with my compass at hand and map book outstretched.

The reality is that outcrop in interior Alaska can actually be quite poor. Due to the yearly freeze-thaw cycle, outcrop is often slumped and ‘creeps’ downhill. This means that despite a lot of rocky exposure outcrop often cannot be relied on for measuring structural features such as foliation, folding or vein orientation. This resulted in a lot more float mapping than I had anticipated. Thick vegetation away from ridgetops meant that outcrop and float were also often obscured, leaving huge parts of the map devoid of information. I quickly realized that in some places outcrop was as sparse as it was in the outback.

A new set of skills were also required to understand geochemical signatures and dispersion patterns. This was not only due to the effects of topography and mountainous terrain but also because of unusual weather phenomena, such as solifluction formed by the freeze-thaw of permafrost. This made the interpretation of geochemical data an entirely new challenge.

The second myth: helicopter-assisted drilling means that you have more options on where you can drill.

Due to the remoteness and a lack of roads, most exploration drilling in Alaska is only possible with the assistance of a helicopter. Unlike Western Australia where the terrain is flat and you can generally drill out a target as desired, the terrain in interior Alaska is reasonably mountainous which limits the number of suitable drill site locations and therefore narrows your drilling options.

I learned very quickly that siting helicopter drill sites can be difficult. What looks like a small hill in 3D software can actually turn out to be a monstrously steep formation when you stand on top of it. Steeper terrain means a taller pad with more timbers, and while it was incredible to see what drill crews can build, larger and more expensive pads could be difficult to justify on greenfield targets.

The ideal drill design and what could actually be achieved were often two vastly different things. It was not always possible to move the rig along strike or down dip to follow up an intercept and you often had to get creative. Key lessons I took away were to always site pads in the field with the pad building crew and that good planning was more necessary than ever.

The third myth: the animals in Alaska couldn’t be any worse than the cohort of venomous creepy-crawlies and snakes in Australia.

When Americans claim that Australia is full of dangerous animals, it’s good to remind them that at least there are no large four-legged predators there that may want to eat you up.

Bears are a serious concern when working in Alaska and precautions must always be taken. Both black and grizzly bears inhabit the interior and it wasn’t uncommon to see them around camp or from the helicopter. Although bears are generally afraid of humans and likely to run away at the sound or scent of us, strict bear safety protocols were always necessary when mapping in the field and running drill programs. My ears are still ringing with the shout, ‘hey bear!’.

Other four-legged creatures that required caution included the Alaskan moose, which although often docile-looking had to be provided with a wide berth due to its notorious unpredictability, as well as wolves and lynx that were occasionally spotted but are generally quite reclusive.

A particularly honorable mention should be also given to the mosquito, rightly nicknamed the Alaska state bird. These menacing pests would form a dense cloud around you in the field and could bite through even the thickest of pants and shirts unless those were smothered in the strongest of Deet. I’d never complain about outback flies again after having experienced Alaskan mosquitos.

The fourth myth: field work would involve hiking along alpine ridge tops and hammering rocks under the endless midnight sun. Whilst there certainly were days of hiking along beautiful ridge tops with incredible views of the Alaska Range, I wasn’t aware of how thick the bush could be until we were battling our way through it. Hiking involved everything, from pushing through dense alder that made for a whole new type of bushwhacking (and getting invariably soaked if it had been raining), to bouncing along on thick tundra that was not unlike walking on a trampoline; to also picking your way down rocky talus slopes covered in ‘banana lichen’ (appropriately named for if it rained, you would invariably end up on your backside). While the vegetation was luckily not viciously spikey like that in Australia it could still make for exerting days in the field.

The fifth myth: drilling can only occur during the summer months.

The summer drilling season in Alaska is typically very short, particularly when drilling at higher elevations. One must wait for the snow to thaw (around May), then for all of the ensuing mud to harden, allowing road access and pad construction (sometimes not until June), then hope you don’t get too fogged out when the rain starts and unable to operate helicopters (in August) and keep drilling until the snow comes again (around October but sometimes as early as late-September).

At the right elevation and terrain, however, I was surprised to learn that drilling can continue throughout the winter. In the right conditions, drillers were able to drill even in -40°F (-40°C), by erecting huts around the rig and keeping everything warm with space heaters thus making sure that the machinery, the drilling muds (and personnel) didn’t freeze. Decked out in Carharrt, racerbacks and heavily insulated boots, North American drillers are a tough breed! One perk of drilling through winter for them was that they had some of the best aurora photos I’d ever seen.

There were numerous other lessons learned, ranging from becoming aware that there wasn’t any running water in the core facility because pipes froze in winter, to not touching a metal doorhandle in -40°F (-40°C), to leaving frozen core in its box until it thawed, to not hiking through muskeg (ever) and also realizing that being exposed to the midnight sun meant chances of overheating and sunburn in the field were just as real in Alaska as they were in Australia.

Working in interior Alaska had some unique challenges but was an incredibly rewarding experience. It is a stunning part of the world, hugely endowed and with new discoveries waiting to be made. Stepping out of our comfort zones and into something new always entails a steep learning curve and opportunities to grow, both professionally and personally. As well as, of course, a few surprises along the way. C