The Origin and Evolution of Holocene Sandur Deposits in Areas of Jökulhlaup Drainage, Iceland

Maizels, Judith K.

doi:10.1007/978-94-011-3150-6_18

Cited by 67 publications

(81 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this paper, we take a general facies model that was developed for Icelandic and Alaskan sandar and apply it, first, to the catastrophic flood deposits in Quincy Basin, Washington, and then by analogy, to the Chryse Basin on Mars. The results for Chryse Basin (Figure 1) [Maizels, 1991]. The high current velocities and discharges associated with sandur-forming outburst events are major factors in the nature of sediment transport along these fans.…”

Section: Chryse Basin Facies Mapmentioning

confidence: 89%

Catastrophic flood sediments in Chryse Basin, Mars, and Quincy Basin, Washington: Application of sandar facies model

Rice¹,

Edgett²

1997

J. Geophys. Res.

View full text Add to dashboard Cite

Section: Chryse Basin Facies Mapmentioning

confidence: 89%

Catastrophic flood sediments in Chryse Basin, Mars, and Quincy Basin, Washington: Application of sandar facies model

Rice¹,

Edgett²

1997

J. Geophys. Res.

View full text Add to dashboard Cite

“…C, concentrations were determined to detect the presence of dissolved C02 in the bulk meltwaters (Arnorsson, 1979;Raiswell, 1984: 52-53;Olafsson, 1988), where, using Stumm and Morgan's (1970: 120) terminology H2COS is taken to represent both C02(aq.) and H2C03, although the former species is much more abundant Raiswell et al, 1980: 24).…”

Section: Hydrochemistry: Sampling and Analytical Methodsmentioning

confidence: 99%

Impact of Subglacial Geothermal Activity on Meltwater Quality in the Jökulsá Á Sólheimasandi System, Southern Iceland

Lawler

Björnsson

Dolan³

1996

Hydrol. Process.

View full text Add to dashboard Cite

The influence of subglacial geothermal activity on the hydrochemistry of the Jokulsa a Solheimasandi glacial meltwater river, south Iceland, is discussed. A radio echosounding and Global Positioning System survey of south-west Myrdalsjokull, the parent ice-cap of the valley glacier S6lheimajokul1, establishes the geometry and position of a subglacial caldera. A cauldron in the ice-cap surface at the basin head is also defined, signifying one location of geothermally driven ablation processes. Background H2S concentrations for the Jokulsa meltwaters in summer 1989 show that leakage of geothermal fluids into the glacial drainage network takes place throughout the melt season. Chemical geothermometry (Na+/K+ ratio) applied to the bulk meltwaters tentatively suggests that the subglacial geothermal area is a high-temperature field with a reservoir temperature of =289-304"C. A major event of enhanced geothermal fluid injection was also detected. Against a background of an apparently warming geothermal reservoir, the event began on Julian day 205 (24 July) with a burst of subglacial seismic activity. Meltwater hydrochemical perturbations followed on day 209 and peaked on day 213, finally leading to a sudden and significant increase in flow on day 214. The hydrochemical excursions were characterized by strong peaks in meltwater H2S, SO:-and total carbonate concentrations, transient decreases in pH, small increases in Ca2+ and Mg2+ and sustained increases in electrical conductivity. The event may relate to temporary invigoration of the subglacial convective hydrothermal circulation, seismic disturbance of patterns of groundwater flow and geothermal fluid recruitment to the subglacial drainage network, or a cyclic 'sweeping out' of the geothermal zone by the annual wave of descending groundwater. Time lags between seismic events and meltwater electrical conductivity responses suggest mean and maximum intraglacial throughflow velocities of 0.032-0.132 m s-l, respectively, consistent with a distributed drainage system beneath Solheimajokull. Because increases in flow follow hydrochemical perturbations, the potential exists to use meltwater hydrochemistry to forecast geothermally driven flood events in such environments.

show abstract

“…This lithofacies originated as a result of a meltwater flood in a tunnel valley, which may have taken place after an episode of increased ice-sheet ablation or a release of a small subglacial reservoir. Transport occurred in a high-energy hyperconcentrated flow (Maizels 1991, Knudsen & Russell 2002, Pisarska-Jamroży 2007. The material was accumulated very rapidly as a consequence of a sudden reduction of transport speed.…”

Section: Coarse-grained Sedimentsmentioning

confidence: 99%

“…The material was accumulated very rapidly as a consequence of a sudden reduction of transport speed. Sediments of this type often constitute records of catastrophic flows (Maizels 1991, Zieliński 1993, Russell & Marren 1999, Knudsen & Russell 2002, Zieliński & van Loon 2003, Fard & Gruszka 2007.…”

Section: Coarse-grained Sedimentsmentioning

confidence: 99%

Structural and textural response to dynamics of fluvioglacial processes of the Rzymsko esker sediments, Central Poland

Frydrych

2016

geol

View full text Add to dashboard Cite

Abstract:The study was conducted in the Rzymsko esker, in the Eastern part of the Turek Upland Plain, within the range of the Warta Glaciation (Saalian II). The form was accumulated in a tunnel valley, which was partially filled with esker sediments. Lithofacies analysis, extended by a detailed analysis of clasts, made it possible to identify a considerable variability of sedimentation conditions. At the initial stage, transport and accumulation of sediments took place in the conditions of high energy hydraulic flows or hyperconcentrated flows. The flow energy rose cyclically, which was recorded as sediments coarsening. Deposits of boulders as well as massive and cross-bedded gravels were identified, a record of catastrophic glacial floods. During the later stage of esker formation, sandy and gravelly sediments were accumulated in an open crevasse. The strong erosional force of subglacial water is confirmed by an extremely high content of local rocks in the gravelly fraction (30-87%) and its very good roundness. Zingg shape analysis (1935) revealed a clear predominance of oblate forms among local clasts and equant fennoscandian erratics. A dependency was also found between the processing method and petrographic characteristics.

show abstract

The Origin and Evolution of Holocene Sandur Deposits in Areas of Jökulhlaup Drainage, Iceland

Cited by 67 publications

References 29 publications

Catastrophic flood sediments in Chryse Basin, Mars, and Quincy Basin, Washington: Application of sandar facies model

Catastrophic flood sediments in Chryse Basin, Mars, and Quincy Basin, Washington: Application of sandar facies model

Impact of Subglacial Geothermal Activity on Meltwater Quality in the Jökulsá Á Sólheimasandi System, Southern Iceland

Structural and textural response to dynamics of fluvioglacial processes of the Rzymsko esker sediments, Central Poland

Contact Info

Product

Resources

About