The Geochemistry of Englacial Brine From Taylor Glacier, Antarctica

AbstractBrine beneath Taylor Glacier has been proposed to enter the proglacial west lobe of Lake Bonney (WLB) as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the geochemistry of the water column of WLB. Year-round measurements from this study are the first to definitively identify brine intrusions from a subglacial entry point into WLB. Furthermore, we excluded input from Blood Falls by focusing on winter dynamics when the absence of an open water moat prevents surface brine entry. Due to the extremely high salinities below the chemocline in WLB, density stratification is dominated by salinity, and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude into the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. High-resolution measurements also reveal under-ice internal waves associated with katabatic wind events, a novel finding that challenges long-held assumptions about the stability of the WLB water column.

Download Full-text

Evidence for subglacial ponding across Taylor Glacier, Dry Valleys, Antarctica

Annals of Glaciology ◽

10.3189/172756404781813970 ◽

2004 ◽

Vol 39 ◽

pp. 79-84 ◽

Cited By ~ 34

Author(s):

Alun Hubbard ◽

Wendy Lawson ◽

Brian Anderson ◽

Bryn Hubbard ◽

Heinz Blatter

Keyword(s):

Equipotential Surface ◽

Dry Valleys ◽

Flow Paths ◽

Dielectric Contrast ◽

Pressure Melting ◽

Reflective Power ◽

Taylor Glacier ◽

High Dielectric ◽

Ice Water ◽

Modelling Data

AbstractIce-penetrating radar and modelling data are presented suggesting the presence of a zone of temperate ice, water ponding or saturated sediment beneath the tongue of Taylor Glacier, Dry Valleys, Antarctica. The proposed subglacial zone lies 3–6 km up-glacier of the terminus and is 400– 1000m across. The zone coincides with an extensive topographic overdeepening to 80m below sea level. High values of residual bed reflective power across this zone compared to other regions and the margins of the glacier require a high dielectric contrast between the ice and the bed and are strongly indicative of the presence of basal water or saturated sediment. Analysis of the hydraulic equipotential surface also indicates strong convergence into this zone of subglacial water flow paths. However, thermodynamic modelling reveals that basal temperatures in this region could not exceed –7˚C relative to the pressure-melting point. Such a result is at odds with the radar observations unless the subglacial water is a hypersaline brine.

Download Full-text

Geochemistry of Ferrar Dolerite sills and dykes at Terra Cotta Mountain, south Victoria Land, Antarctica

Antarctic Science ◽

10.1017/s0954102095000113 ◽

1995 ◽

Vol 7 (1) ◽

pp. 73-85 ◽

Cited By ~ 11

Author(s):

A.D. Morrison ◽

A. Reay

Keyword(s):

Trace Element ◽

Mantle Source ◽

Source Region ◽

Crustal Component ◽

Enriched Mantle ◽

Victoria Land ◽

Trace Element Signature ◽

Geochemical Variation ◽

Element Enrichment ◽

Taylor Glacier

At Terra Cotta Mountain, in the Taylor Glacier region of south Victoria Land, a 237 m thick Ferrar Dolerite sill is intruded along the unconformity between basement granitoids and overlying Beacon Supergroup sedimentary rocks. Numerous Ferrar Dolerite dykes intrude the Beacon Supergroup and represent later phases of intrusion. Major and trace element data indicate variation both within and between the separate intrusions. Crystal fractionation accounts for much of the geochemical variation between the intrusive events. However, poor correlations between many trace elements require the additional involvement of open system processes. Chromium is decoupled from highly incompatible elements consistent with behaviour predicted for a periodically replenished, tapped and fractionating magma chamber. Large ion lithophile element-enrichment and depletion in Nb, Sr, P and Ti suggests the addition of a crustal component or an enriched mantle source. The trace element characteristics of the Dolerites from Terra Cotta Mountain are similar to those of other Ferrar Group rocks from the central Transantarctic Mountains and north Victoria Land, as well as with the Tasmanian Dolerites. This supports current ideas that the trace element signature of the Ferrar Group is inherited from a uniformly enriched mantle source region.

Download Full-text

Charting the “Bloody” Brine Flows from an Antarctic Glacier

Eos ◽

10.1029/2021eo210648 ◽

2021 ◽

Vol 102 ◽

Author(s):

McKenzie Prillaman

Keyword(s):

Historical Record ◽

Field Observations ◽

Taylor Glacier

Photographs and field observations yield a more complete historical record of the ebbs and flows of the so-called Blood Falls on Taylor Glacier.

Download Full-text

The influence of environmental microseismicity on detection and interpretation of small-magnitude events in a polar glacier setting

Journal of Glaciology ◽

10.1017/jog.2020.48 ◽

2020 ◽

Vol 66 (259) ◽

pp. 790-806

Author(s):

Chris G. Carr ◽

Joshua D. Carmichael ◽

Erin C. Pettit ◽

Martin Truffer

Keyword(s):

Data Stream ◽

Original Data ◽

Source Model ◽

The Other ◽

Detection Capability ◽

Small Magnitude ◽

Glacial Environments ◽

Hybrid Data ◽

Taylor Glacier ◽

Two Degree Of Freedom

AbstractGlacial environments exhibit temporally variable microseismicity. To investigate how microseismicity influences event detection, we implement two noise-adaptive digital power detectors to process seismic data from Taylor Glacier, Antarctica. We add scaled icequake waveforms to the original data stream, run detectors on the hybrid data stream to estimate reliable detection magnitudes and compare analytical magnitudes predicted from an ice crack source model. We find that detection capability is influenced by environmental microseismicity for seismic events with source size comparable to thermal penetration depths. When event counts and minimum detectable event sizes change in the same direction (i.e. increase in event counts and minimum detectable event size), we interpret measured seismicity changes as ‘true’ seismicity changes rather than as changes in detection. Generally, one detector (two degree of freedom (2dof)) outperforms the other: it identifies more events, a more prominent summertime diurnal signal and maintains a higher detection capability. We conclude that real physical processes are responsible for the summertime diurnal inter-detector difference. One detector (3dof) identifies this process as environmental microseismicity; the other detector (2dof) identifies it as elevated waveform activity. Our analysis provides an example for minimizing detection biases and estimating source sizes when interpreting temporal seismicity patterns to better infer glacial seismogenic processes.

Download Full-text

Seismic multiplet response triggered by melt at Blood Falls, Taylor Glacier, Antarctica

Journal of Geophysical Research Atmospheres ◽

10.1029/2011jf002221 ◽

2012 ◽

Vol 117 (F3) ◽

pp. n/a-n/a ◽

Cited By ~ 18

Author(s):

Joshua D. Carmichael ◽

Erin C. Pettit ◽

Matt Hoffman ◽

Andrew Fountain ◽

Bernard Hallet

Keyword(s):

Taylor Glacier

Download Full-text

Ice-Sheet flow in the Vicinity of Southern Victoria Land, Antarctica: Implications for Glacial Chronology

Journal of Glaciology ◽

10.1017/s0022143000014982 ◽

1979 ◽

Vol 24 (90) ◽

pp. 483

Author(s):

David J. Drewry

Keyword(s):

Ice Sheet ◽

East Antarctica ◽

Small Surface ◽

The North ◽

Ice Surface ◽

Glacial Chronology ◽

Victoria Land ◽

Dry Valley ◽

Radio Echo Sounding ◽

Taylor Glacier

Abstract Systematic radio echo-sounding during three seasons since 1971–72 has produced data on the configuration of the ice sheet in East Antarctica. In the sector extending inland from southern Victoria Land, the ice sheet exhibits a large ridge which drives ice towards David Glacier in the north and Mulock and Byrd Glaciers to the south. Within 100 km of the McMurdo dry-valley region soundings along ten sub-parallel lines (c. 10 km apart) provides detail on ice surface and flow patterns at the ridge tip. A small surface dome lies just inland of Taylor Glacier. The surface drops by 100 m or more before rising to join the major ridge in East Antarctica.

Download Full-text

Review of the manuscript "SPATIAL PATTERN OF ACCUMULATION AT TAYLOR DOME DURING THE LAST GLACIAL INCEPTION: STRATIGRAPHIC CONSTRAINTS FROM TAYLOR GLACIER" by J. Menking et al.

10.5194/cp-2018-53-rc4 ◽

2018 ◽

Author(s):

Anonymous

Keyword(s):

Spatial Pattern ◽

Last Glacial ◽

Taylor Glacier ◽

The Last Glacial

Download Full-text

Acoustic in-ice positioning in the Enceladus Explorer project

Annals of Glaciology ◽

10.3189/2014aog68a035 ◽

2014 ◽

Vol 55 (68) ◽

pp. 253-259 ◽

Cited By ~ 5

Author(s):

Dmitry Eliseev ◽

Dirk Heinen ◽

Klaus Helbing ◽

Ruth Hoffmann ◽

Uwe Naumann ◽

...

Keyword(s):

Space Mission ◽

Positioning System ◽

Test Scenario ◽

Full System ◽

Ice Surface ◽

Curved Trajectories ◽

Future Space ◽

Glacier Ice ◽

Taylor Glacier ◽

Acoustic Positioning

AbstractThe Enceladus Explorer project is a preparatory study for a future space mission to Saturn’s moon, Enceladus. Its ultimate goal is to probe liquid-water pockets below the ice surface of Enceladus for signatures of life. A probe could be based on the IceMole concept, which melts curved trajectories through the ice. In the Enceladus Explorer project, a specialized IceMole probe for a terrestrial test scenario is in development. The goal of this exploratory study is to probe water from a liquid crevasse close to Blood Falls at Taylor Glacier, Antarctica. To navigate such a probe it is essential to be able to determine its position and monitor its trajectory. Part of the navigation system is the in-ice acoustic positioning system. For this, the head of the IceMole is equipped with acoustic sensors, which receive signals from synchronized acoustic emitters situated at the ice surface. Based on the measured propagation times, the speed of sound in ice and the positions of the emitters at the surface, the position of the IceMole can be determined by trilateration techniques. Here we present the developed acoustic positioning system, which is designed to track the in-ice melting probe up to distances of 100 m in glacier ice. Results from full-system tests in water and a first field test on Morteratschgletscher, Switzerland, are discussed.

Download Full-text