Pearse Valley- 2 Women drill team at it again!

Jan 21st/22^nd

A quick preamble- On our way to Pearse we flew over Blood Falls, I could only snap a few  quick photos, but this site deserves mention . It is one of the more well-known sites in the Dry Valleys, and one of the coolest. Blood Falls discharges from Taylor Glacier as a cold (~7 X) ancient marine brine, rich in sulfates and oxidized iron, castiung the reddish hue that gives the falls its name. 

Microbiology wise- the sulfur rich waters are dominated by autotrophic sulphur oxidizing thiomicrospira identified through molecular surveys of the water, biomass levels were 10⁵ cells/mL. 

Pearse was spectacular, and can’t adequately be described in words, but if it could, majestic, awesome (in the very literal sense) would be some words to pull out. Mars and I had the place to ourselves and we made good use and time of it. We set up camp in a beautiful section of the valley right next to a permanently ice covered lake, and close to a glacier, a quick lunch and it was off to work .

 This permanently ice covered  lake (Lake Joyce) is a really fascinating spot for me as a microbiologist- folks like Dale Anderson dive into the frigid waters here (‘coolest’ job?) and provide a glimpse of just how versatile and extreme life can be. What little light gets through the ice cover of this lake provides the energy for cyanobacterial life (primary producers) within the lake.  These organisms form calcifying microbial mat structures that look like an alien world. 

We weren’t there to sample the lake though, we were interested in the soils found in this dry valley. In this particular valley wet streaks can be observed on some of the valley slopes. Could soils in these wet-streaks harbour active microbial life? We took some  surface and ice-cemented permafrost samples from both the dry and ‘wet’ streaks, as well as measured soil flux in situ with the LosGatos Ultraportable Greenhouse gas analyzer that we had brought to the field to measure CO₂ and CH₄ flux from soils. 

One day and night of work in Pearse, and it was onward to University Valley. 

Soil collars for respiration measurements set up in the dry (left) and wet (right) soils in Pearse valley. 

The cold and aridity of the Dry Valleys are the predominant reasons that this region is considered one of the most Mars like places on Earth.