The archive consists of about 1 km of permafrost cores. The archive has a capacity of about 2.5 km of core.  Most samples within the archive come from the Froese group's work over the last 20 years, largely from NW Canada (Yukon and NWT) dating from modern permafrost to ancient samples up to 800,000 years old. Notable collections include the geotechnical cores from the Sentinel Inuvik-Tuktoyaktuk Highway, and other geotechnical donations from companies. All samples in the archive are tracked using eLab LIMS with QR codes to the cooler and shelf location within the archive. As of 2023, all samples in the archive are also within our Lab database tracking system.  

Coolers with permafrost samples within the PACS Archive.

The core processing place is equipped with bandsaws, large tile cutting saw for splitting cores, and a variety of rock and tile saws and layout space for processing permafrost cores and frozen materials.  The cutting room is kept at -7 degrees C and equipped with CO2 and warm-temperature sensors.

We have a Nikon XTH 225 ST Industrial CT Scanner equipped with fixed and rotating target sources.  This allows imaging to a resolution of ~ 3 microns for small objects, and commonly 20-50 microns for core-sized samples.  It can manage samples up to 35 cm x 35 cm x 50 cm and up to 50 kg with varying energies from ca. 60-225 kV.  More details on sample requirements, rates and examples can be found on the PACS CT page.  We have developed methods in the lab for scanning of frozen materials in the room-temperature cabinet for up to several hours while holding temperatures well below 0º C.

We use a Geotek MSCL to image and characterize permafrost cores for frozen bulk density using a 137Cs gamma source (which we use to estimate ice content), magnetic susceptibility, and optical imagery.  Our recent work on MSCL applied to permafrost can be found in our paper in The Cryosphere. More details on rates for this service can be found here.

The PACS Lab analytical space includes 2 Picarro L-2130i water isotope analyzers, mastersizer grain size system, drying furnaces, muffle furnaces, freeze-driers, analytical balances, MetroToledo pH and EC meters, digital core viewing computers and most anything you could want for working with permafrost cores. More details on rates for these services can be found here.

We have two Hepa-filtered clean rooms with positive air pressure and anti-rooms that are used for preparation of samples for microbial and ancient DNA extractions from permafrost samples. These labs have been purposefully built to avoid contamination in permafrost research. The first clean lab allows reduction of samples and removal of contamination either through water-reduction, following the approach we used in Alireza Saidi-Mehrabad's PhD presented here, or through physical reduction of outer contaminants presented in Tyler Murchie's PhD and, also presented much earlier in D'Costa et al. (2011) using spiked contaminant tracers. 

We have a second clean lab with postive air pressure HEPA-filtered air with anti-room for sedimentary (ancient environmental) DNA (sedaDNA) extractions from permafrost samples. Only samples reduced to single vial size in the Clean lab enter this lab to avoid contamination. This lab is set up to use either soil DNA kits (e.g. DNEasy PowerSoil Pro kits) or the Dabney cold-spin extraction method discussed in Tyler Murchie's recent papers for permafrost sedimentary ancient DNA (sedaDNA).