Tephrochronology of Late Wisconsin deglaciation and Holocene glacier fluctuations near GlacierPeak, North Cascade Range, Washington
Déglaciation ; Etats-Unis ; Fluctuation glaciaire ; Glaciation ; GlacierPeak ; Glacier alpin ; Gphy ; Géographie de l'Amérique ; Holocène ; Montagne ; North Cascade Range ; Pléistocène supérieur ; Quaternaire zones moyennes ; Téphrochronologie
Tephra layers near GlacierPeak in the North Cascade Range provide limiting dates for four periods of alpine glacier advance. Field relations suggest that late Wisconsin alpine glaciers last advanced prior to the eruption of tephra layers from
GlacierPeak about 11.250 yr B.P. Late Wisconsin deglaciation in the central North Cascades was complete prior to the GlacierPeak tephra eruptions. Glaciers again expanded in the early Holocene about 8400-8300 yr B.P. Soil formed in alpine meadows during
an episode of mild climate in the middle Holocene prior to at least two intervals of glacier expansion: an older episode between 5100 and 3400 yr B.P., and a younger episode within the last 1000 yr.
Travail basé sur les observations réalisées en juin-juillet 1979 au cours de l'expédition au Diran Peak (7.268m) dans le NW du Karakoram. Etude du glacier de Minapin. (JLG).
The age of GlacierPeak tephra in west-central Montana
Amérique du Nord ; Analyse à la microsonde électronique ; Cendre volcanique ; Datation ; Datation radiocarbone ; Etats-Unis ; GlacierPeak ; Géochimie ; Géographie de l'Amérique ; Holocène ; Montagne ; Montana ; Quaternaire zones moyennes ; Rocky
glass and horublende phenocrysts from this ash layer indicate that they are similar in major-element chemistry to those of GlacierPeak layer G previously considered to be about 12,000 yr old or older.
China ; Climatic variation ; Fluctuations of glaciers ; Glacial lake ; Glacier surges ; Glaciers ; Glaciology ; Hydrology ; Karakoram ; Statistics ; Xizáng Zizhiqu
The drainage of the Kyagar glacier dammed lake and the Tram Kangri glacier dammed lake at the upper Shaksgam is the mean reason for glacier outburst floods in the Yarkant river. These floods are characterized by high peak discharge, big rising rate
, small total volume and short duration. The floods happen mostly from late summer to early autumn. Frequent glacier outburst floods indicate glacier advance and climatic variations.
Aerial photography ; California ; Glacier ; Moraine ; Palaeo-environment ; Photointerpretation ; Rock glacier ; Sierra Nevada ; Snow line ; Thermokarst ; United States
-shaped rock glaciers) and many Matthes moraines are ice-cored and glacial in origin. Matthes and Recess Peak ELA (equilibrium-line altitudes) gradients along the crest evidently depend strongly on local orographic effects rather than latitudinal climatic
The AA. describe rock glaciers and Matthes-age (Little Ice Age) moraines in the Sierra Nevada, and discuss their formation, extent, and climatological significance. They conclude for the Sierra that most valley-floor rock glaciers (i.e., tongue
trends, indicating that simple linear projections and regional climatic interpretations of ELA gradients of small glaciers may be unreliable.
Mid-Holocene GlacierPeak and Mount St. Helens We tephra layer detected in lake sediments from southern British Columbia using high-resolution techniques
The goal of this paper is to present results of ongoing investigations on fluvial sediment transport and fluvial sediment yields during thermally and pluvially induced runoff events in the glacier-fed Erdalen catchment in Nordfjord, western Norway
Age, distribution, and stratigraphy of GlacierPeak tephra in eastern Washington and western Montana, United States
de Marys Frog, de l'état de Montana, et datation au radiocarbone des dépôts des lacs associés. Les couches de tephra peuvent être regroupées d'après leur provenance (le sommet Glacier, mont Mazama, mont Saint Helens et une source inconnue
). L'application de techniques plus sensibles apparaît nécessaire pour pouvoir subdiviser plus en détail les tephras du sommet Glacier.
Contrainte de cisaillement ; Expérimentation ; Glace ; Glacier rocheux ; Impact ; Pergélisol ; Périglaciaire ; Reptation ; Sol gelé ; Technique de recherche
Creep ; Experimentation ; Ice ; Impact ; Periglacial features ; Permafrost ; Research technique ; Rock glacier ; Shear stress
, the peak shear strength increased with decreasing volumetric ice content and increasing strain rate. The tests showed the dependency of the mechanical failure and deformation mode of frozen soils on the loading conditions. Such investigations
on artificially frozen soils samples may help in developing a better understanding of rock glacier and general permafrost dynamics at temperature close to the melting point of ice.
due to changes in water pressure in the subglacial hydraulic system. If this is the case, the water pressure apparently reaches a maximum a couple of months after the peak summer melt, contrary to observations on some temperate glaciers.
The surface speed of the lower one-fourth of Storglaciären increases from about 13 mm d near the terminus to slightly under 40 mm d 800 m up-glacier from the terminus. The speed reaches a maximum in late summer and early fall, and then decreases
On September 16th, 1986, an ice avalanche from a hanging glacier near the K2 peak at 7 800 m, Karakorum, triggered a massive avalanche of ice and snow. Ice and snow, impacting on the path, formed a dust cloud at the advancing tip. On the basis
are presented for the first time, especially nivation hollows in the uppermost zone, and the Jezere cirque where a smaller glacier, unknown until recently, existe at the peak of the glaciation. - (IKR)
Origin and development of tafoni in Tunnel Spring Tuff, Crystal Peak, Utah, USA
This paper concerns a type of cavernous weathering that is well developed on the flanks of Crystal Peak. The recesses, with their visors and large cavities, have the character of typical tafoni. Tafoni at Crystal Peak are remarkable because
. The reconstruction of glaciers and calculations of equilibrium line altitude (ELA) were carried out. On the north-eastern side of the highest peak Sveti Jure, two small cirque glaciers were formed and their ELA was 1515 m a.s.l. - (IKR)
tundra, from the Indian Peaks area, Colorado and Glacier National Park, Montana, are combined. Using the Mantel test, the correlation between difference and distance is discussed. In monitoring programs such as GLORIA, the assesment of observed changes
[b2] USGS Northern Rocky Mountain Science Center, West Glacier, Montana, Etats-Unis
Afrique du Sud ; Coulée boueuse ; Drakensberg ; Dynamique de versant ; Dépôt de pente ; Glacier rocheux ; Lesotho ; Montagne ; Paléo-environnement ; Périglaciaire ; Quaternaire ; Solifluxion ; Variation climatique
Climatic variation ; Lesotho ; Mountain ; Mudflow ; Palaeo-environment ; Periglacial features ; Quaternary ; Rock glacier ; Slope deposit ; Slope dynamics ; Solifluction ; South Africa
This study describes the morphology and discusses the likely palaeogeomorphic processes of blockstreams and debris deposits on the Popple Peak and Njesuthi-Mafadi south-facing slopes in the Drakensberg. The geomorphic evidence provides much needed
Cliff ; Glacier ; Glacier retreat ; Ice ; Insolation ; Model ; Mountain ; Photogrammetry ; Radiation ; Tanzania ; Tropical zone
A review on those ice cliffs, which are mostly associated with dry calving events, is presented. The focus is on the persistent, rarely-calving ice cliffs on the plateau glaciers of Kibo, the main peak of the Kilimanjaro massif, Tanzania. Modelling
Two decades of responses (1986-2006) to climate by the Laurichard rock glacier, French Alps
Alpes ; Années 1986-2006 ; Climat ; Dynamique glaciaire ; France ; Glacier rocheux ; Géophysique ; Hautes-Alpes ; Impact ; Montagne ; Pergélisol ; Périglaciaire ; Réchauffement climatique ; Température du sol
Alps (The) ; Climate ; Climatic warming ; France ; Geophysics ; Glacier dynamics ; Hautes-Alpes ; Impact ; Mountain ; Periglacial features ; Permafrost ; Rock glacier ; Soil temperature
The Laurichard active rock glacier is the permafrost-related landform with the longest record of monitoring in France, including an annual geodetic survey, repeated geoelectrical campaigns from 1979 onwards and continuous recording of ground
temperature since 2003. These data were used to examine changes in creep rates and internal structure from 1986 to 2006. The control that climatic variables exert on rock glacier kinematics was investigated over three time scales. Between the 1980s
and the early 2000s, results and discussion about the correlation between surface movement, snow thickness and ground sub-surface temperatures. Finally, unusual surface lowering that accompanied peak velocities in 2004 may be due to a general thaw of the top