Polar Eolian Sand Transport: Grain Characteristics Determined by an Automated Scanning Electron Microscope (QEMSCAN®)

Speirs, Johanna; McGowan, Hamish A.; Neil, D. T.

doi:10.1657/1523-0430(07-029)[speirs]2.0.co;2

Cited by 27 publications

(26 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…McCauley et al, 1981;Helgren and Prospero, 1987). However, Speirs et al (2008) and Ayling and McGowan (2006) measured threshold velocities of 5.3 ms − 1 and 5.5 ms − 1 respectively for dry sand in the cold conditions of the McMurdo Dry Valleys (Fig. 1) and are here considered to be a good estimate for the SMS area.…”

Section: Wind Regime and Aeolian Transportmentioning

confidence: 76%

“…However, the detailed mechanics of grain movement in niveo-aeolian environments are poorly known (McKenna Neuman, 1993;Speirs et al, 2008). In addition, entrainment, transport and deposition of aeolian sediment in polar regions depend largely on local factors, including the availability and grain size distribution of the source area and surface conditions of the area of deposition.…”

Section: Wind Regime and Aeolian Transportmentioning

confidence: 99%

See 1 more Smart Citation

Aeolian sediment flux from sea ice into Southern McMurdo Sound, Antarctica

Atkins

Dunbar

2009

Global and Planetary Change

106

View full text Add to dashboard Cite

Section: Wind Regime and Aeolian Transportmentioning

confidence: 76%

Section: Wind Regime and Aeolian Transportmentioning

confidence: 99%

Aeolian sediment flux from sea ice into Southern McMurdo Sound, Antarctica

Atkins

Dunbar

2009

Global and Planetary Change

106

View full text Add to dashboard Cite

“…Velocities required for entrainment of dry fine sand in the McMurdo Dry Valleys have been determined to be 5.3 ms 21 to 5.5 ms 21 (Ayling and McGowan 2006;Speirs et al 2008a). Integrating these data on velocity required for transport with recorded wind speeds suggests that eolian transport of sediment onto sea ice at Explorers Cove is not common, but is a significant process.…”

Section: Eolian Processesmentioning

confidence: 97%

Sediments Beneath Multi-Year Sea Ice: Delivery By Deltaic and Eolian Processes

Miller¹,

Fan²,

Bowser³

2015

Journal of Sedimentary Research

View full text Add to dashboard Cite

Little is known about land-to-sea sediment transport and deposition in polar regimes with multi-year sea ice such as at the mouth of the Taylor Valley, one of the Dry Valleys in Antarctica. This study integrates textural analysis of 574 coastal subaerial and nearshore submarine sediment samples with data from sediment traps and with published grain-size analyses of offshore sea-ice surface and submarine sediments to reconstruct transport and depositional processes from the shoreline to , 8 km offshore.Sediment, primarily sand sized, is transferred into the marine environment via two processes: 1) erosion, transport, and deposition of till by ephemeral meltwater streams that deliver sediment to the subaqueous part of the delta built over the last , 7,500 years, and 2) onshore to sea-ice sediment transport by wind during rare but powerful foehn wind events. Because the distributaries flow into quiet water beneath the sea ice, most of their load is dropped close to shore, but a small amount of finegrained sediment, mostly silt, is carried kilometers offshore, probably by low-density, low-salinity plumes.Wind deposits sediment on the sea ice with median grain size decreasing from medium to fine sand within 1.5 km of the shoreline; even offshore sea-ice sediment contains very little silt and almost no clay. Nearshore the sea-ice sediment is coarser than that on the underlying seafloor, but in a few kilometers offshore the median grain sizes of the seafloor and sea-ice sediments are similar; this reflects a mixture of sea-ice-rafted eolian sediment and fine-grained delta-derived sediment transported beneath the sea ice.This system is unusual in the relative effectiveness of the transport systems. The feeble distributaries deposit their sediment load immediately upon entering the quiet water, and only a minor amount of silt and clay is carried seaward under the ice. In contrast, winds deposit coarser sediment on the nearshore sea ice and carry fine sand . 7 km offshore, although the amount and grain size of sediment is attenuated within 1.5 km of shore. Melting of the sea ice drops sediment onto the seafloor, where it mixes with the delta-derived silt and clay. Similar combinations of eolian and fluvial transport processes may have operated in polar regimes dominated by multi-year sea ice in the past. Understanding of the modern processes in Explorers Cove may aid recognition of ancient sediments deposited under multi-year sea ice, as well as help predict future changes in processes around Antarctica as the distribution of multi-year sea ice shifts in response to climate change.

show abstract

“…Proportions of fine silt-sized and clay fractions cannot be distinguished at the step width of 10 μm used in this study and are summarized in Table 2 as fraction b 20 μm. Owing to the fact that grain size information is obtained from image analysis this data set is not identical with grain sizes determined by sieve techniques (Speirs et al, 2008). But the grains size data of Table 2 clearly underline the fine grained character of the river sediments used in this study.…”

Section: Resultsmentioning

confidence: 82%

“…Image analysis has been shown as highly suitable technique for the characterization of fine-grained non-consolidated sediments (e.g. Speirs et al, 2008). To avoid loss of fine-grained matter or salts, the samples were not washed.…”

Section: Mineralogical Characterizationmentioning

confidence: 99%