Lake‐ice blisters, terra nova bay area, northern victoria land, antarctica

Abstract

Ice blisters, typically 0.2-0.8 m high and 5-20 m long, develop annually on perennially frozen lakes in Northern Victoria Land. They are believed to be caused by hydrostatic pressures generated through progressive freezing of solute-rich water beneath the lake-ice cover during winter. Lakeice blisters in the study area differ from icing blisters described from the northern hemisphere. The latter are caused by hydraulic pressures and are found at locations such as river beds or spring sites on sloping terrain. The Antarctic lake-ice blisters reflect the occurrence of dry-based perennially frozen lakes with high salt contents in an extremely cold and arid environment.

Multi-Temporal Investigation of the Boulder Clay Glacier and Northern Foothills (Victoria Land, Antarctica) by Integrated Surveying Techniques

“…The salinity level (2.13%) and conductivity (4091 µS/cm) were comparable to brackish water, while the temperature inside the blister, due to the solar-radiation effect, was consistent, with the presence of a liquid phase. On BCG, Guglielmin et al [28] recorded similar conductivity values (2800 µS/cm), drilling an ice layer in the blister at 174-176.5 cm depth. The drill also allowed to sample the brine and slush layer beneath the ice at a temperature of -13.2 and -15.4 • C, with a conductivity between 66,000 and 97,000 µS/cm, which suggests salinities at least four to five times that of seawater.…”

“…The marine origin of the moraine ice-cored deposits is clearly evidenced by marine remains dated between 25 and 37 ka by C14 [24], and rock-salt extrusions on the moraine surface (see Figure 3). Several kinds of ice features related to melt waters are present on the moraine, such as frost mounds, icing blisters, and Lake-Ice Blisters (LIB), [15,[26][27][28]. Water circulation onto/into the salt-rich deposits generates brines that can remain unfrozen under ice coverage [28].…”

“…A reference digital orthophoto and a detailed DTM of the area (including BCG) were built through the analysis of a block of four panchromatic GeoEye-1 satellite stereo images (December 2012; nadir resolution = 0.41 m; dynamic range = 11 bits/pixel) in order to perform the comparison with the current morphology. The exterior orientation of the GeoEye-1 images was performed by the bundle-adjustment analytical model, using 25 tie points and 16 Ground Control Points (GCPs), measured through a Several kinds of ice features related to melt waters are present on the moraine, such as frost mounds, icing blisters, and Lake-Ice Blisters (LIB), [15,[26][27][28]. Water circulation onto/into the salt-rich deposits generates brines that can remain unfrozen under ice coverage [28].…”

T‐RFLP Fingerprinting Analysis of Bacterial Communities in Debris Cones, Northern Victoria Land, Antarctica

“…The age of the frost mound is younger than 1020 ± 70 14 C yr BP, while the till that generally covers the surface of the Boulder Clay area is of Late Pleistocene age and attributed to the Ross Sea I glaciations (Orombelli et al , ). The analysed frost mound formed during the late Holocene, in the middle of a perennially ice‐covered lake, which is located on the sublimation till, overlying the buried Pleistocene relict glacier ice (Guglielmin et al , ).…”

The origins of Antarctic rock glaciers: periglacial or glacial features?

“…Although Continental Antarctica and the Ross Sea region in particular, remain among the few areas on the planet over which air warming has not occurred (Doran et al, 2002;Guglielmin and Cannone, 2012;Guglielmin et al, 2014;Turner et al, 2014), several pieces of evidence of rapid landscape changes have been detected in the last 10 years, including fluvial erosion and the thermokarst phenomena in the Dry Valleys (Fountain et al, 2014). In contrast, in the more glaciated Northern Victoria Land, only a small amount of evidence of climatic-related landscape changes has been detected (Guglielmin et al, 2009).…”