Ida Lønne

High-Arctic terrestrial slopes have received limited systematic research interest, but increased vulnerability related to regional warming has driven the call for better knowledge of the dynamics of these systems. Studies of sediment transport from a plateau area in Adventdalen, Svalbard, and associated slopes extending to sea level demonstrate tha...

Svalbard is a key area for the investigation of glacial surges, and almost two centuries worth of field observations exists from this region. Studies have shown that the course of a surge and the associated formation of landforms are strongly influenced by basinal factors, and that the broad range of variables involved can hamper interpretations an...

Glacial surges in Svalbard are protracted and characterized by individual dynamic evolution, in contrast to many other areas, which calls for a subdivision of the classic two-phased surge cycle. A dominating part of the ice masses seem to have a surge potential and this represents a considerable challenge for palaeoclimatic studies. Glaciological a...

Glacial surges are periods of fast flow, often limited in space and time, and driven by internal conditions which are not fully explained. The quantity and variety of documented case-studies and settings demonstrate that the critical variables are difficult to isolate. In an alternative approach, two surges from the same basin were compared at Fridtj...

Abstract: The study focuses on the terminal moraine of a fast-flowing, temperate tidewater glacier that protruded in Oslofjorden trough, southern Norway, during one of the re-advances of the receding Fennoscandian Ice Sheet in the Younger Dryas time. Allostratigraphic mapping is used to reconstruct the moraine’s morphodynamic development, showing h...

Modern studies indicate that the kinematic behaviour of tidewater glaciers is a crucial part of ice-sheet dynamics. A similar relationship may be expected for ancient ice sheets, but can the kinematics of ancient tidewater ice margins be recognized? The paper addresses this methodological issue by pointing to the high-resolution stratigraphic recor...

The Fridtjovbreen glacier surged for 12 yr (1991 2002). The maximum extent with a run-out distance of ˜4 km was reached after 7 yr. On the basis of ice-front behavior, the active phase of the surge can be divided into four stages: increased ice flow but stable ice-front position (30 months), advancing ice front (54 months with an average advance ra...

The Fridtjovbreen glacier surged for 12 yr (1991–2002). The maximum extent with a run-out distance of �4 km was reached after 7 yr. On the basis of ice-front behavior, the active phase of the surge can be divided into four stages: increased ice flow but stable icefront position (30 months), advancing ice front (54 months with an average advance rat...

The late culmination of the Little Ice Age (LIA) on Svalbard allows a detailed reconstruction of the landscape's response to the subsequent climatic warming. The study area comprises a small glacier (400–1000 m a.s.l.), on the south side of Adventfjorden (78°11′N) that was polythermal during the LIA and turned into a passively down-wasting cold-bas...

Raised marine beach gravel at 62 m a.s.l. in Bolterdalen indicates that the inner part of Adventfjorden, central Spitsbergen, was ice-free shortly before 10 025±160yr BP. A glacier advanced across the regressive, frozen beach terraces and into shallow water, 58 m above the present sea level, where a small wave-influenced ice-contact delta was forme...

Study of a Holocene fan delta in Adventfjorden, Spitsbergen, provides new insight into the nature of high-arctic coastal sedimentation and deglaciation dynamics. The fjord-side, gravelly Gilbert-type fan delta began to form at the local marine limit c. 10 ka BP, supplied seasonally with sediment by meltwater from a cirque glacier left behind by the...

We have used ground-penetrating radar (GPR) to search for victims of snow avalanches on Svalbard and in the Swiss Alps in 2001. The two accidents occurred 2 days apart in February 2001 and claimed a total of five lives. It was not possible to locate some of the victims with traditional search methods such as snow avalanche probes and dogs. GPR was,...

A knowledge of permafrost conditions is important for planning the foundation of buildings and engineering activities at high latitudes and for geological mapping of sediment thicknesses and architecture. The freezing of sediments is known to greatly affect their seismic velocities. In polar regions the actual velocities of the upper sediments may...

Studies of the Holocene deglaciation of Svalbard, Norwegian Arctic, indicate that the receding ice masses retreat quickly from fjords, but commonly turn into isolated, cold-based stagnant glaciers in high-relief onshore areas, where they then melt very slowly. In the cold climate of polar desert, the glaciers and permafrost active layer release wat...

Englacial debris structures, morphology and sediment distribution at the frontal part and at the proglacial area of the Scott Turnerbreen glacier have been studied through fieldwork and aerial photograph interpretation. The main emphasis has been on processes controlling the morphological development of the proglacial area. Three types of supraglac...

The Mona moraine in southern Norway is a sedimentary ridge, 3.5 km long, formed at the mouth of a shelf trough during a late Younger Dryas readvance of the Scandinavian ice sheet. The moraine architecture, sedimentation processes, and record of ice-front behavior have been reconstructed in a high-resolution allostratigraphic framework on the basis...

Ice-cored lateral and frontal moraine complexes, formed at the margin of the small, land-based Rieperbreen glacier, central Svalbard, have been investigated through field observations and interpretations of aerial photographs (1936, 1961 and 1990). The main focus has been on the stratigraphical and dynamic development of these moraines as well as t...

The Egge-Lyngås moraine is a sedimentary ridge 140 m thick and 3.5 km long, comprising a gravelly succession underlain by marine mud and dated to ca. 9800 yrs BP. Allostratigraphic study based on a sedimentological analysis of outcrop sections and ground-penetrating radar profiles indicates that the ridge is an ice-contact submarine fan formed by a...

Moraines are products of ice-front advances, and their development as continuous ridges reflects linear sediment supply. The grounding-line source supplies diamicton derived by the shear-driven subglacial processes of sediment remoulding, mixing, push/squeeze deformation and transfer by freezing to and melting off the glacier sole, as the advancing...

The Mona moraine in southern Norway is a sedimentary ridge, 3.5 km long, formed at the mouth of a shelf trough during a late Younger Dryas readvance of the Scandinavian ice-sheet. The moraine architecture, sedimentation processes and record of ice-front behaviour have been reconstructed in a high-resolution allostratigraphic framework on the basis...

Allostratigraphic mapping of the internal facies architecture of marine moraines reveals the development history of ice-contact sedimentary systems. The new method for a high-resolution analysis of the dynamic stratigraphy of moraines provides important information on the ice-front behavior, glacier dynamics, and regional climatic conditions. Based...

The postglacial sedimentation in Endalen has been studied to gain insight into the the deglaciation pattern and Holocene climatic changes in Spitsbertgen area. The study focuses on the record of sediment dispersal by meltwater flow and the development of gravelly colluvial fans on the valley flanks. The documentation includes field evidence from th...

Endalen is a north-trending deglaciated valley in west-central Spitsbergen, scoured in Tertiary sedimentary rocks and surrounded by bedrock plateaux. The valley is ca. 450 m deep and 6 km long, spans an altitude range of 250 to 20 m, has a longitudinal gradient of 0.08 and is drained axially by a braided stream. Marine palaeobeaches have been recog...

The Kregnes "moraine" ridge in Gauldalen, a north-bending valley south of Trondheim, is a Gilbert-type delta formed at a Younger Dryas glacier terminus. The gravelly delta consists of a north-dipping foreset, 150 m thick, comprised of turbidites, debrisflow beds and debrisfall deposits. The bottomset consists of turbiditic sand and mud layers. The...

Seismic stratigraphy from a 65 km long transect of the Lake Melville fjord basin, southeast Labrador, Canada, has revealed seven cycles of ice-front advance-retreat, from a stratigraphic interval which regionally is correlated to 10-9 ka BP. A maximum thickness of 400 m of glacimarine sediments, ice-contact submarine fans and associated fine-graine...

An 8 m long carcass of a bowhead whale (Balaena mysticetus) melted out from remnant glacier ice in the lateral moraine of the Jemelianovbreen glacier in August 1996. Folded and sheared sediment bands in the ice suggest that the whale was incorporated during an advance of the glacier. The whale's longitudinal axis was oriented parallel to the direct...

An 8 m long carcass of a bowhead whale (Balaena mysticetus) melted out from remnant glacier ice in the lateral moraine of the Jemelianovbreen glacier in August 1996. Folded and sheared sediment bands in the ice suggest that the whale was incorporated during an advance of the glacier. The whale's longitudinal axis was oriented parallel to the direct...

A shallow marine turbiditic lobe, inferred to be associated with an ice-contact delta, was deposited during the last glaciation (Weichselian) at Svalbard, the Norwegian Arctic. The postglacially raised sandy lobe is exposed in a 200-m-long river-section and exhibits six units that reflect an early phase of glaciomarine mud deposition followed by th...

The 140-m-thick 'end-moraine' ridge at Egge-Lyngas comprises a lower mud overlain by a 100-m-thick gravelly succession representing an ice-contact submarine fan formed around 9800 years BP. Outcrop studies from the upper 80 m thickness of the fan are discussed, focusing on the fan's 3-D architecture. sedimentary facies and processes. Foreset beds o...

A modern moraine complex in front of a small subpolar valley glacier in Svalbard, the Scott Turnerbreen glacier, has been investigated by ground-penetrating radar (GPR) (pulseEKKO(TM)IV system). The proglacial area is characterized by low relief ridges, which are concentric about the present ice front, and locally dissected by meltwater channels. E...

The characteristics of ice-contact glaciomarine systems are reviewed, based on a range of Weichselian and Holocene examples from the fjordal basins in Norway and Svalbard. These depositional systems occur as large morphological ridges, ''end-moraines'' (including ''push-moraines''), which are coarse grained and show large-scale foreset bedding. The...

The depositional history of an ice-contact delta in Sørfjorden has been reconstructed, based on two sections, 100 and 900 m long. Five major sedimentary facies have been distinguished within the delta's foreset, and their geometry and spatial organization have been mapped in the outcrops through the use of photographs. Facies 1 comprises chaoticall...

Most scientists have concluded previously that the west coast of Spitsbergen, Svalbard, remained ice-free during the late Weichselian, between 25,000 and 10,000 yr B.P. We conclude that the glaciation was more extensive. Terraces that were postulated to have been ice-free are covered by a thin, late Weichselian till. Sudden drop in the marine limit...

A 20 m thick shallow marine sequence, capped by a Late Weichselian lodgement till, is exposed for 200111 along the river in Linnedalen on the west coast of Svalbard. Five formations are recognized: Formation A, the oldest, consists of a shallow marine, proglacial fan, of channelized sandy turbidites, possibly fed from an ice‐contact deposit. Format...

The glacial history of Svalbard and the Barents Sea during the Late Weichselian has been much debated during the last few years; reviews are presented by Andersen (1981), Boulton et al. (1982), ElverhBi & Solheim (1983) and Vorren & Kristoffersen (1986). In our opinion (Mangerud et al. 1984) it is now demonstrated that a relatively large ice-sheet...