Formation of the Neoglacial surge moraines of the Klutlan Glacier, Yukon Territory, Canada
The Klutlan Glacier is a valley glacier 82 km long emerging from the Icefield Ranges of the St. Elias Mountains. It is one of at least 200 surging glaciers identified in western North America. During about the past 1200 yr, the glacier has deposited
at its terminus a series of at least 7 surge-related Neoglacial ice-cored moraines. Lithologic characteristics of the Klutlan moraines suggest that they have resulted principally from the surging of the tributary Nesham Glacier, which periodically injects
a lobe of medial and lateral moraines and the underlying ice into a more slowly moving Klutlan ice stream. Subsequent surges of the main ice carry the Nesham surge lobes to the Klutlan terminus as discrete geomorphic features. For the past 400 yr a Nesham
Observations of debris-rich naled associated with a major glacier surge event, Disko Island, West Greenland
and disappeared within 5 years. The fine-grained debris was deposited on top of outwash deposits on bars and banks. Observations at the margin of surrounding glaciers revealed that only surge-type glaciers in their quiescent phase had proglacial naled assemblages
During the 1995-98 surge of Kuannersuit Glacier, Disko Island, turbid winter runoff produced an extensive naled accretion with a distinct debris-rich stratification. After surge termination the summer occurrence of naledi gradually decreased
, although these lacked incorporated debris. This indicates that surge-type glaciers have a significant impact on the occurrence of naledi.
Freezing fronts and their possible influence upon processes of subglacial erosion and deposition
Ablation sous-glaciaire ; Accumulation sous-glaciaire ; Eau interstitielle ; Eau sous-glaciaire ; Erosion sous-glaciaire ; Glace de base ; Glacier ; Géographie physique ; Géomorphodynamique ; Lit glaciaire ; Moraine de fond ; Point de gel
that deal with the various effects that freezing front movement may have on pore water, consolidation, shear strength, and likely diagenetic characteristics of subglacial deposits. The influence upon erosional and depositional processes will be outlined
and a mechanism related to potential surge-like conditions within the subglacial zone postulated.
of storm surges. Annual winter storms set off erosional overwash processes which formed elongate washover channels. During stable stages of sea level horizontal beach deposits and foredunes were accumulated, the latter forming the present dune area
drilled at selected sites along the radar profiles. Based on detailed radar- and sediment-facies analysis the model of the southern barrier spit describes the major episodes of spit evolution. It shows that southerly barrier spit accretion into the tidal
inlet was interrupted by erosional events during severe storm surges. Between distinct storm surges longshore currents along the west coast of Sylt provided the southern spit-end with sediment. Spit growth during this phase depended on the interval
Cold area ; Glacial features ; Glacial surge ; Iceland ; LANDSAT ; Remote sensing ; Sandur ; Thematic Mapper
By using remote sensing techniques including satellite synthetic aperture radar (SAR), Landsat TM, and laser altimetry in combination with field-based methodologies, the AA. discuss the geomorphic signature of this catastrophic flood that generated
to the late Holocene depositional history of the sandur and the hydrologic conditions occuring during the event itself.
High energy coastal sedimentary deposits| an evaluation of depositional processes in Southwest England
This paper examines the evidence for historical storm surges and tsunamis and shows that both high magnitude events have been documented over the past 250 years in southwest England.
upper and lower parts present evidence of the accumulation of material, the middle is characterised by a loss of material. Deposits preserve traces of five storm surges during which the waterline reached to the base of the dunes. Analysis of dune
deposits themselves also revealed variation as regards development trends. In the past there have been periods in which accumulation was dominant, during which new dune ridges were created and old ones rebuilt, as well as periods characterised
Glacial landscapes, like most landscapes, reflect both erosion and deposition. Consequently, careful study of glacial landforms and sediment provides a wealth of information on these processes. A brief review illustrates the use of such information
that the surges responsible for the deposits were wet.
The eruptive history of the Tihany Peninsula (Lake Balaton, Hungary) has been studied in detail to understand the evolution of volcanic and tectonic structures. Tectonic and depositional features indicate a maar-type origin of the Outer Lake
The ignimbrite was deposited as a series of pyroclastic flows emanating from the caldera region of the Tindfjallajokull volcano and is associated with a ground-surgedeposit. The main magma type was comenditic, and the phenocrysts reveal slight
by organic matter accumulation rather than mineral sediment deposition with water and entrapped gases occupying the majority of the soil volume. Such organic-based fresh and brackish marsh soil are more fragile than mineral based marsh soils and are subject
to impact by salt water intrusion and hurricane storm surge forces. The Davis Pond diversion is a conduit between the Mississippi River and the coastal marshes of Barataria basin currently reintroducing river water into the basin leading to lower basin
Fluvial deposition on the Shoalhaven deltaic plain, Southern New South Wales
New research from the Shoalhaven deltaic plain prompts revision of ideas on fluvial deposition in coastal New South Wales. Thermoluminescence (TL) analysis indicates that there were at least 2 and probably 4 phases of Pleistocene deposition spanning
much of Last Interglacial and Glacial times. Holocene infilling was faster than previously thought. The pattern of channel development which has controlled fluvial sedimentation and the apparent impact of tsunami surges on these Holocene features
) on sediment cores collected from 2 mangrove forest sites within Everglades National Park, Florida (USA). Enhanced rates were found in an upper layer that corresponded to a storm surgedeposit. Accretion rates within the storm deposit were compared to overall
for OC burial in marine wetlands. With tropical storms being a frequent occurrence in this region the resulting storm surgedeposits are an important mechanism for maintaining both overall accretion and OC burial rates.
rates. These rates were found to be matching or exceeding average sea-level rise reported for Key West, Florida. Organic carbon burial rates within the storm deposit were compared to overall burial rates. The overall rates are similar to global estimates
Features of Middle Pleistocene sandur deposits in the Netherlands
) in The Netherlands are classified based on the type of deposition. (AIS).
The sandur deposits discussed below appear to be much similar to alluvial fan deposits. Only minor differences may occur which are related to the nature of the source area (slopes, availability of non-consolidated material) and to climatic
conditions. In the introduction a synopsis is given concerning river types and their deposits in general, represented in the deposits of this part of the North Sea Basin| subsequently, Neogene and Quaternary fluvial deposits (including sandur deposits
sediments are crucial in this regard because they assist greatly in the identification of particular microfossil assemblages that can be used to distinguish coastal sediments deposited by palaeotsunamis from storm surges and also from those sediments
Accumulation rate ; Aeolian features ; Glacial surge ; Loess ; Oregon ; Palaeo-environment ; Palaeoclimate ; Pleistocene ; Quaternary ; Tephrochronology ; United States of America
This paper evaluates the roles that Juniper and Cold Springs Canyons have played in the distribution and thickness of loess in the southwestern Palouse. These topographic features and their associated glacial outburst flood and eolian deposits
provide an ideal test of the topographic trap model of Mason et al. (1999) and in so doing provide insight into timing of loess deposition since the last glacial maximum (LGM)
Relative dating of Quaternary depositsbased on P-wawe velocities in weathered granitic clasts
The technique makes use of a microseismic timer to determine the compressional wave velocity (clast-sound velocity) in each clast of a group chosen from a single deposit. From these data a groupe mean velocity is determined that is proportional
to the age of the deposit : the youngest deposits having the highest velocities. The clast-sound velocity method can be applied to many unconsolidated bouldery deposits up to approximately one million years old.