Holly’s third (and final) update from the 2015 field season

(January 8, 2016)

We’re back! From the field that is – the journey stateside has yet to begin.

What a wonderfully successful season we’ve had, I’ll do my best with brevity, but you can only compress 4 weeks of excellent sciencing (yes, it’s a verb) so much.

Our first field site was called Otway Massif, a small range at about 2,500 m elevation comprising a portion of the Transantarctic Mountains. One can imagine that site selection is perhaps the most integral component of deep fieldwork – while also the most difficult. The continent is so vast and unexplored that beyond satellite photography, very minimal information regarding the Massif exists. Dr. Bromley selected the location based almost purely on physical clues he was able to garner from that imagery. His aim was to select a site where Pliocene moraines, the objective of our sampling, were well preserved and clearly discernible on foot as well as aerially. The key component being a low, if not nonexistent, relief surface upon which the moraines rest. This ensures very little erosion due to gravity.

So what are these “moraines” I speak of? Simply put they are ridges of rock debris left at the terminus of a body of glacial ice, providing a very tangible indicator of former ice extent. Our goal at these sites was to traipse all about, sampling rocks from what we hope are Pliocene moraines and date them, eventually painting a cohesive picture of the evolution of the east Antarctic ice sheet during the Pliocene.

ridge2-1024x681

A moraine ridge, a mound of debris deposited by the glacier, extends down the center of the photograph.

We found moraines at Otway. Many. After being deposited in the white wilderness via twin otter (a VERY small type of aircraft Dr. Bromley fondly refers to as vomit buckets) we set up camp close to the ice margin. From our tents the ice dipped down a gentle slope to meet a vast valley chock full of rocks ripe we could sample (and then promptly lug back up the big hill to camp). Our first week here was wildly successful, much sciencing was done and many chocolate bars were consumed. In the blink of an eye it was time for the twin otters to swoop in and transport us to the next site located about 20 kilometers away and known as the Dominion range.

tents-1024x768.jpg

Tents set up at the camp on Shackleton glacier.

To fly a twin otter it appears three things are required; a robust beard, a thick Canadian accent and clear skies. On the day we were scheduled for transport our pilots Phil and Kelsey possessed all the above – except, unfortunately, the clear skis. Alas! we thought, such is travel in Antarctica. We’ll we wait it out – surly it will get better soon. 3 days later we had strung ropes about camp to get safely from tent to tent through the magnificent winds and blowing snow. 5 days later we were running low on fresh reading material. 8 days later the chocolate supply was wearing precariously thin and we were seriously considering breaking into the emergency stash. The day finally came when we awoke to clear skies and Chris yelling “plane coming in a hour!” Hoorah! To the Dominion we go!

While Dr. Bromley and I finished up taking down camp Chris and Maggie took the first flight over with the intent to scope out the location and begin camp set up. You can imagine our dismay when Chris came over the radio and said “We won’t be making it to the dominion this year”. Apparently after 5 attempts to land the pilots had determined it simply wasn’t feasible. There was no safe stretch upon which to touch down. After a moment of mourning for our lost moraines we began to ponder alternatives. We had at least a week more of scheduled field time and intended to us it.

Where there is a will (and the weather cooperates) there is a way. We found ourselves shortly thereafter at Roberts Massif  – a site we knew very little about and were not anticipating visiting until next season. Consequently, the only map we had was a rather vague chart used by the pilots to navigate the region. What we did have was feet hungry for roaming after almost two stagnate weeks. After two days at Robert’s Massif we had covered much ground and had stumbled upon some very promising moraines – which, in the days proceeding, we set out to sample. Overall our impromptu trip to Robert’s was wildly successful, we collected over 80 samples, had the opportunity to explore the area for the next season and even managed to roast a fine pork loin for Christmas dinner. Such class!

sampling-769x1024.jpg

Collecting a rock sample that will later be dated using surface exposure-age dating methods.

Sampling-notes-768x1024.jpg

With each sample collection, we carefully describe a number of characteristics including notes about the collection site and the sample itself (such as weathering, size of boulder, and rock type).

The day we were finally pulled from the field was a bit surreal. The time in the field raced by like most things in life tend to do and and soon enough we were back at McMurdo station enjoying some VERY necessary showers and fresh(ish) vegetables. Now what? The sampling is only the beginning of this project. Before we can draw any conclusions they will need to be cleaned up and sent to Greg at Berkeley Geochronology Center to be dated. (Temporally that is, Greg will not be wining and dining the rocks).  Next year the process will be repeated all over again! If anything, I hope this description has provided you with some sense of the scale at which scientific projects in the Antarctic operate. It is a massive and somewhat odd machine, but the US Antarctic Program has allowed us and countless others we met here an amazing opportunity.  It’s been a joy to be involved and relay this experience to those reading this! Thank you from all of us on team I-177 for following the blog and you interest in our work! That’s all for updates from the field, but keep an eye out for posts once we start getting dates back, yahoo!

Cheers!

Bonus Fun Facts from the Field

  • The average temperature ranged from -4 Fahrenheit to 2
  • Wind chill considered, you can bump that down to -15 to -10
  • The strongest wind gust recorded was 50 knots per hour, the average being about 35.
  • 168 samples were collected in total
  • We spent a total of 23 days camped in the field
  • Immeasurable volumes of chocolate bars were consumed during said time
  • Green things simply do not grow here. In fact, nothing really grows here. Apparently there is some type of lichen able to withstand the conditions but the only life we saw for those 23 days were ourselves (although my socks could be considered alive by week 3)
  • Fieldwork is THE BEST.
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s