by Philip T. Staudigel
The purpose of the trip was to gain a better understanding of the magnetic field at high latitudes. Over the three week span of the trip, the joint SIO/Bergen team trekked across the 30 km long island, drilling the multiple lava flows.
Jan Mayen is a volcanic island, and a relatively young one. Estimated to be younger than 600,000 years, it is located near the Jan Mayen Fracture Zone. The island has one large volcano, dominating the northern side of the island, Beerenberg. This active volcano, last reported to have erupted 30 years ago, is now covered in ice year-round.
There is very little animal life on the Island. Seagulls and puffins are the only animals, and the vast majority of plantlife is moss, with a few flowers growing in small colonies. The birds live off fish and each other. Predatory seagulls, with a wingspan of five feet, hunt and kill the other birds on the Island, and tend to be very agressive toward hikers. The puffins, however, are unafraid of hikers and bring much sought-after color to the otherwise bleak rockfaces they inhabit.
At 71° N, Jan Mayen is well north of the Arctic Circle, meaning over most of the summer, the sun never sets. This can make it difficult for people to sleep, however, after an eight hour hike, sleep never seems to be far away.
The trip was not easy: countless meteorological and technological pitfalls made the trip quite difficult. However an enduring spirit kept us going. From the beginning, weather was a major concern. For instance, in order to orient samples quickly, a sun-compass is normally used to measure the azimuth of a drill core. But Jan Mayen is nearly always wrapped in fog, making sun-compassing impossible most of the time. To remedy this, we developed a system using a brunton compass, lasers and a matched pair of GPS systems to accurately measure the azimuth. Fortunateley, this problem was forseen before the trip, giving plentey of time to prepare.
The drill, used for boring holes into interesting rocks, had a problem. The drill bit, used in previous expeditions, required a different motor than the two brought on the expedition. The bit used a 6-tooth connection, while both drills used a seven-tooth connection. This presented an interesting conundrum, as it would be impossible to bring a drill from anywhere else in the world, because the C-130 only comes every two months. The only solutions were to either take hand samples, or create an adaptor. Thankfully, one of the mechanics in Olonkinbyen, the Norwegian facility on the island, was able to make an adaptor, saving the expedition.
These two pitfalls aside, the trip went as smoothley as could be expected, twenty-seven sites were taken, twenty-three of which we expect to provide excellent paleomagnetic data. The other four were taken exclusiveley for geochemical purposes.
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