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This paper documents the glaciovolcanic landsystem of the Brekknafjoll–Jarlhettur ridge in Central Iceland. Glaciolacustrine diamict is found beneath, and in association with, a complex assemblage of pillow lava, lava breccias and hyaloclastites. Three depositional environments are identified: glaciolacustrine fan, pillow lava dome, and hyaloclastite fan. These subaqueous environments occurred both simultaneously and at different times along the volcanic fissures which underlie the ridge and have given rise to a complex facies architecture. This facies architecture provides evidence that the ridge evolved in a time transgressive fashion during several episodes of volcanism, some of which may have been punctuated by periods of ice erosion. Associated with the ridge are large-diapiric folds in diamict and gravel which form by the loading and lateral displacement of saturated diamict beneath the developing volcanic pile. A depositional model is presented which emphasises the glaciolacustrine component and the time transgressive nature of the glaciovolcanic landsystem. Much of the eruption occurred in subglacial to englacial lakes or vaults, which were probably linked by water and sediment exchange. The initial subglacial vaults appear to have extended beyond the fissure limits and were infilled by glaciolacustrine diamicts, subaqueous outwash and the eruption of pillow lava. This was followed by the eruption of hyaloclastite sand and breccia forming an elongated fan.

This paper describes the internal architecture of a push moraine formed by a winter-spring surge of Hagafellsjokull-Eystri (Iceland) in 1998/99. The sedimentary architecture of this push moraine consists of a multilayered slab of glaciofluvial sediments with a monoclinal structure that has been displaced laterally by the advancing ice margin. The crest and ice-distal face of the moraine consist of subhorizontal sediment sheets, while the ice-proximal face dips steeply (45° to 90°) towards the ice margin. The core of the moraine consists of frozen sediment and thin slabs of glacier ice are embedded in its proximal face. The sediment slabs are characterized by both brittle and ductile styles of deformation. We argue that the observed variation in deformation style is dependent on whether the glacial foreland was frozen or unfrozen at the time of displacement. Frozen foreland would behave in a brittle fashion, while unfrozen foreland is likely to have deformed in a more ductile manner. The associated spatial variations in the degree of foreland freezing could be explained by variation in ice-marginal snow cover. We conclude that the thermal regime of the foreland, and the timing of the ice advance, is of importance to the style of internal deformation found within ice-marginal push moraines.

Although eskers are frequently described glaciofluvial landforms, they are poorly understood. To assist with the interpretation of Pleistocene examples, modern analogue data are required. This paper documents the morphology, sedimentology and formation of a 650 m long esker system in front of the high-arctic glacier Vegbreen in Svalbard. The esker is located between the Neoglacial maximum and the present ice front and appears to have formed both as a supraglacial trough-fill and as a channel/conduit-fill along the suture formed by two confluent glacier lobes. A range of sedimentary facies is preserved within this ridge system providing evidence for braided rivers, ephemeral lakes, episodic flow regimes and sediment gravity flows. This case study provides an important analogue for glaciofluvial sedimentation between retreating ice lobes.

The tidewater glacier complex of Kongsvegen/Kronebreen, at the head of Kongsfjorden in north-west Spitsbergen, has advanced rapidly several times since its Neoglacial maximum. Two such advances, 1869 and 1948, are well constrained in time and space and are widely interpreted as glacier surges. During the 1869 advance an ice-dammed lake formed on the western side of Ossian Sarsfjellet. This ice-dammed lake is associated with a thrust moraine complex. Four lake levels are identified, two of which are associated with rock-cut shorelines implying a degree of lake stability. The history of this lake, the nature of the ice dam and its relationship to the thrust moraine complex are discussed. The lake history spanning 28 to 35 years is used to assess the ice-marginal dynamics of the Kongsvegen/Kronebreen glacier. It is concluded that, contrary to previous suggestions, the rapid advance of this tidewater glacier may simply be an example of a non-climatic ice-marginal fluctuation, of the type common to tidewater glacier, as opposed to a glacier surge. A second ice-dammed lake, to the east of Ossian Sarsfjellet, formed sometime after 1869 as the ice retreated, and still exists today. This largely supraglacial lake is associated with a very different geomorphological assemblage, which has a poor long-term preservation potential. The geomorphological characteristics of the two lakes on Ossian Sarsfjellet are compared and used to discuss the problems associated with the recognition of ice-dammed lakes within the Pleistocene record. On the basis of the evidence presented here, ice-dammed lakes may be more common during deglaciation than currently suggested.

The occurrence of glaciolacustrine diamict fans on the south side of volcanic tuyas in the Laugarvatn area (Iceland) is reported. These fans are composed of sheets of diamict, gravel and sand, and contain little or no primary volcanic material. They post-date the volcanic pile within the tuyas and appear to have been deposited in subglacial water-filled cavities, confined to the down-ice side of the tuyas. It is suggested that these subglacial water bodies formed as result of an enhanced geothermal heat flux associated with the tuyas. The volume of glacial sediment within the fans implies that either basal sediment loads were high in this sector of the former ice sheet or that ice flow converged towards the tuyas during their formation concentrating basal sediment into the lee-side cavity and fan. The glaciolacustrine diamict fans add to our knowledge of the landforms and sediments associated with tuyas and may also provide evidence of ice flow convergence at thermal anomalies.

This paper describes aspects of the landform-sediment assemblage produced by a recent surge of Hagafellsjokull-Eystri. This surge occurred during the winter and early spring of 1998/1999 and consequently advanced into a partially frozen foreland. Two aspects of this landform-sediment assemblage are considered. First the evidence for a frozen subglacial sediment layer beneath a lateral piedmont lobe formed during the surge is reviewed. This sediment layer consists of blocks of glacier ice set within a matrix of frozen sediment and was injected into basal crevasses to form a network of crevasse-squeeze ridges prior to freezing. The sediment layer appears to provide evidence of subfreezing deformation at the termination of the surge. Secondly the paper examines the detailed tectonic facies within a push-moraine formed along the eastern latero-frontal margin of the glacier during the surge. Architecturally this push moraine consists of a multi-layered slab of glaciofluvial sediments with a monocline structure that has been displaced laterally by the advancing ice margin. The sediment slabs within this monocline are characterized by both brittle and ductile styles of deformation. The authors argue that the observed variation in deformation style may be explained by spatial variation in the extent to which the glacial foreland was frozen or unfrozen at the time of displacement. Areas of frozen foreland would have behaved in a brittle fashion, while unfrozen areas deformed in a more ductile manor. Both these aspects of the landform-sediment assemblage examined in this paper appear to be the product of the seasonal timing of the surge. Not only do they add to our understanding of surge-type landsystems, but they also illustrate the potential of winter advances around the margins of some temperate glaciers to explore the coupling between glaciers and frozen proglacial sediments.

Original article can be found at: http://www.sciencedirect.com/science/journal/00370738 Copyright Elsevier B.V. [Full text of this article is not available in the UHRA]

We report evidence of deformation at sub-freezing temperatures beneath Hagafellsjokull-Eystri, an Icelandic surge-type glacier. The bed of a piedmont lobe that advanced during the 1999 surge comprises deformed blocks of glacier ice set within frozen sediment. This material has also been injected through overlying ice to form a network of crevasse-squeeze ridges. This layer contains evidence for two phases of deformation under contrasting rheological conditions: (1) deformation under relatively warm conditions, when the blocks of glacier ice acted as competent clasts within an unfrozen deforming matrix and (2) subsequent deformation at sub-freezing temperatures when the ice blocks were attenuated into the surrounding frozen matrix along fractures and planar shears enriched with excess ice. This suggests that the basal thermal regime of the advancing ice margin changed from warm-based to cold-based during the surge event. The persistence and potential prevalence of subglacial sediment deformation at sub-freezing temperatures has fundamental implications for our understanding of the dynamic behaviour, sediment flux and geomorphic ability of cold-based glaciers.

This paper defines the principal architectural elements present within the Pleistocene, glaciolacustrine basin-fill of the Copper River Basin in Alaska. The Copper River drains an intermontane basin via a single deeply incised trench through the Chugach Mountains to the Gulf of Alaska. This trench was blocked by ice during the last glacial cycle and a large ice-dammed lake, referred to as Lake Atna, filled much of the Copper Basin. Facies analysis within the basin floor allows a series of associations to be defined consistent with the basinward transport of sediment deposited along calving ice margins and at the basin edge. Basinward transport involves a continuum of gravity driven processes, including slumping, cohesive debris flow, hyperconcentrated/concentrated density flows, and turbidity currents. This basinward transport results in the deposition of a series of subaqueous fans, of which two main types are recognised. (1) Large, stratified, basin floor fans, which extend over at least 5 km and are exposed in the basin centre. These fans are composed of multiple lobes, incised by large mega-channels, giving fan architectures that are dominated by horizontal strata and large, cross-cutting channel-fills. Individual lobes and channel-fills consist of combinations of: diamict derived from iceberg rainout and the ice-marginal release of subglacial sediment; multiple units of fining upward gravels which grade vertically into parallel laminated and rippled fine sands and silts, deposited by a range of density flows and currents derived from the subaqueous discharge of meltwater; and rhythmites grading vertically into diamicts deposited from a range of sediment-density flows re-mobilising sediment deposited by either iceberg rainout or the ice-marginal release of sediment. (2) Small, complex, proximal fans, which extend over less than 2 km, and are exposed in the southern part of the basin. These fans are composed of coalescing and prograding lobes of diamict and gravel deposited both directly by subaqueous meltwater and from sediment-density flows. These lobes are cross-cut by a range of sand and gravel-filled troughs and channels cut by subaqueous outwash, and either overlie or are overlain by horizontal sheets of gravel and diamict deposited from a range of sediment-density flows. The fans are, therefore, characterised by a complex, and laterally variable facies, architecture. Water depth, proglacial topography, stability of meltwater portals and sediment supply may all be important in determining the type of subaqueous fan present at any one location. We suggest that the Copper River basin-fill is dominated by packages of sediment containing multiple subaqueous fans with individual fans separated by units of diamict. Each sediment package is in turn separated from the next by a palaeo-landsurface shaped by interstadial/interglacial fluvial processes and by volcanic debris flows.

Applying the principles of structural geology and sedimentology to glacial depositional features indicates that the High-Arctic provides the best analogues for late glacial landforms in the British uplands.

This paper provides the first comprehensive description and interpretation of Pleistocene glacigenic deposits exposed in a cliff section at Thurstaston on the Wirral Peninsula, NW England. The section occupies a strategic position where the Irish Sea ice sheet impinged on the English Midlands and North Wales coast. The section comprises six lithofacies: diamicton, gravel, sand, laminites, mud and cobble pavements. The diamicton lithofacies can be divided into an upper, clast-poor sandy diamicton and multiple units of a lower, clast-rich sandy diamicton. Both diamictons exhibit cobble pavements. The two diamicton lithofacies are distinguished on the basis of textural composition, clast lithology, clast shape, clast surface features and clast macrofabrics. Between the diamicton lithofacies are interbeds of sands and gravels of variable thickness. Minor mud and laminites also occur in close association with the sands and gravels. Both the diamictons are interpreted as basal, deformation tills with the interbeds of the sand, gravel and mud lithofacies as indicators of subglacial meltwater flow and ponding. The cobble pavements are interpreted as the result of clasts sinking within, or to the base of, the deforming layer. The sedimentary succession at Thurstaston is best explained by the advance and subsequent recession of a single terrestrially based ice sheet during the Late Devensian. There is no evidence at Thurstaston to suggest a glaciomarine origin for the Late Devensian deglaciation sediments on this margin of the Irish Sea basin. The evidence at Thurstaston points to constructional deformation with the net accretion of till and interbeds caused by the upward migration of the deforming layer base.

In ice-cored landform assemblages, the process of resedimentation via sediment-flow is important in determining the morphology and sedimentary facies distribution after the ice core has melted. This paper documents the sediment-flow processes associated with the resedimentation of an ice-cored lateral moraine at Kongsvegen, Svalbard. Decay of the ice-cored lateral moraine is dominated by the development of a sediment-flow fan, which has an ‘hour-glass’ form in plan. The fan comprises a broad source area on the crest of the lateral moraine separated from the fan surface, composed of tessellated flow lobes, by a narrow ice-floored channel system. The principle sedimentary facies associated with this fan include matrix-supported diamictons, laminated silts and fine sands. The evolution of this fan and the likely end-products after complete deglaciation are discussed, and this paper contributes modern analogue data relevant to the interpretation of the Pleistocene landform and sediment record.

A range of subsidence structures associated with desiccation-crack piping are described from the drained proglacial lake bed of Hagavatn, Iceland. Subsurface drainage along desiccation cracks leads to the formation of small-scale subsidence structures. These subsidence structures include linear fissures, located along the limbs of desiccation cracks, and crater-like depressions that form at crack intersections. The controls on subsurface piping are discussed and the role of these subsidence structures in determining the pattern of surface drainage on the former lake bed is identified. Preservation potential of these sedimentary structure is considered to be high, given renewed lacustrine sedimentation. The potential for similar structures to be found in the geological record is considered likely, and consequently these structures may be of importance in the interpretation of crack networks in the geological record as being of subaerial as opposed to subaqueous origin.

Landform–sediment assemblages associated with two ice-dammed lakes, one active and one fossil, at Heinabergsjokull in southeast Iceland are described. The current ice-dammed lake (Vatnsdalur) is dominated by a large aggradational terrace, as well as an excellent suite of shorelines. The second fossil ice-dammed lake dates from the Neoglacial maximum of Heinabergsjokull (c. 1887) and drained during the late 1920s. This lake is associated with a suite of shorelines and ice-marginal glaciolacustrine fans. The sedimentology of one of these fans is described. Between 50 and 70% of the sediment succession is dominated by ice-rafted sediment, although rhythmites, matrix-rich gravels, sands and graded sand–silt couplets are also present. A range of intra-formational, soft-sediment deformation structures are present, consistent with liquefaction and deformation associated with loading, current shear, and iceberg calving. The landform–sediment assemblages described from Heinabergsjokull provide important data for the interpretation of Pleistocene ice-dammed lakes.

This paper describes the landform and sediment assemblage produced by a surge (in 1948) of the Kongsvegen/Kronebreen tidewater glacier complex in northwest Spitsbergen. The main geomorphological products of this advance are two large thrustmoraine complexes on opposite sides of the fjord, and a system of geometrical ridges revealed on glacier decay. The thrust-moraines are composed largely of diamicton, sandy and muddy gravel, gravelly sand, sand and mud, with minor laminites. All of these appear to be derived from the fjord floor and represent both fine fjord basin sediments and coarse grounding-line fan deposits. Thrusting was the principal mode of emplacement of the sediment onto the adjacent land areas during the 1948 advance. However, the geomorphology of the thrust-moraine complexes on either side of the fjord is quite different, reflecting a transpressive regime on the southwest side (mainly long ridges) and a normal compressive regime on the northeast side (short ridges and pinnacles of a ‘hummocky’ nature). The advance which produced the moraine complex has previously been attributed to a surge of Kongsvegen, but the glaciological and geomorphological evidence suggests that the advance involved both Kongsvegen and Kronebreen. Comparison of the landform assemblage produced by this event with that produced by other tidewater glacier surges demonstrates the diverse range of landform assemblages associated with glacier surges, or other episodes of rapid flow, within glaciomarine environments.

Marthabreen is a 7 8km long valley glacier in SW Spitsbergen. The glacier is partially covered by a layer of angular debris derived from rockfall in its accumulation area, pierced in places by pinnacles and ridges of glaciofluvial sediment. These concentrations of glaciofluvial sediment fall into three categories: (1) debris pinnacles; (2) longitudinal sediment dykes; (3) longitudinal ridge accumulations. Debris pinnacles are slabs of sediment (predominantly sands, gravels and cobbles) elevated to the glacier surface along thrusts. Longitudinal sediment dykes are low ( 1m high) ridges of sorted sand and gravels which are not associated with penetrative ice structures. Their occurrence downglacier of sediment dykes and debris pinnacles suggests that they originate as supraglacial or englacial channels or tunnels filled by sediment derived from the dykes or thrusts. The presence of large quantities of glaciofluvial sediment on the surface of Marthabreen does not imply englacial water flow at high levels within the glacier, but is related to ice deformational processes such as thrusting and folding of debris-rich stratification. Copyright # 1999 John Wiley & Sons, Ltd.

The interpretation of glacigenic diamictons is a subjective process, for which quantitative support is frequently sought from parameters such as clast shape and fabric. It has been widely suggested that different glacigenic diamicton facies possess distinct clast-fabric signatures. This paper examines this concept using a data set of 111 clast fabrics, and a synthesis of published results. Eigenvalues are calculated and compared for a variety sedimentary facies. It is concluded that clast fabric alone is not able to discriminate between different glacigenic facies, and it is argued that clast fabric offers little quantitative support in the interpretation of glacigenic sediments. It is suggested, therefore, that although clast fabric may continue to have a role as an indicator of relative strain at specific sites, its use in the discrimination of glacigenic facies is limited. Consequently, we should be much more selective in undertaking such analyses in the future. Copyright © 1999 John Wiley & Sons, Ltd.

Three moraine complexes containing large rafts of fractured-bedrock formed by small cirque glaciers occur in Reindalen, Svalbard. Glaciotectonic landforms cored by rock rafts have been described from mid-latitude ice sheets of Pleistocene age in the past, but we believe this to be the first time large-scale bedrock rafts have been reported from moraines formed by small cirque glaciers. These moraine complexes consist of an imbricate stack of thrust slabs composed of fractured-bedrock and diamicton. Although the exact mechanism are unclear, we suggest that these moraines form by the displacement of subhorizontal strata within the cirque floor to form an initial stack of rock-cored thrust slabs, which subsequently confine the cirque glacier. Subsequent glacier advances, against this "barrier," establishes a strong compressive regime within the glacier snout, which leads to erosion and moraine development. Estimates of the thickness of the rock rafts are used to derive erosion rates, which are an order of magnitude greater than those previously reported for arctic regions.

Well-rounded gravels are described from moraine-mound complexes, diamicton forefields and modern englacial thrusts at the margins of four glaciers on the northern side of Broggerhalvoya, northwest Spitsbergen. Their shape charcteristics are compared with modern and fossil glacigenic, modern beach and Early Weichselian beach gravels from this peninsula. The best discriminators of the well-rounded gravels have been found to be the percentage-frequency roundness histograms, the roundness mid-point and roundness range diagrams and the sphericity-roundness plots. It is concluded that the gravels have been derived by englacial thrusting from Early Weichselian or last interglacial beaches in the inner parts of the fjord and in the low level cirques when sea level reached at least 50m a.s.l. and deposited the beach gravels. The discrimination between gravel in basal diamictons, proglacial outwash and modern beaches is difficult as the reworking has resulted in little particle shape change. The potential major problem caused by reworking in the glacial environment is emphasised, especially when clast shape comparisons from modern environments to older sediments are used.

Although there is an established relationship between geological structure and the morphology of certain glacial erosional landforms, the role of lithology is less clear. This is particularly true of the surface wear characteristics of glaciated bedrock. In order to examine this relationship, the surface wear characteristics of eight recently deglaciated metamorphic bedrock slabs in the Kongsfjorden area of Svalbard were mapped and recorded using detailed “micro‐maps.” Features recorded included lee‐side fracture surfaces, lee‐side cavities, and the location and depth of open joints and quartz veins. On schist, glacial erosion is favored by situations where ice movement is parallel to the trend of the bedrock foliation. In these situations, cavities may be elongated in the direction of ice flow. On more homogeneous lithologies such as marble, cavity formation is suppressed and more uniform glacially abraded rock surfaces develop. On all the metamorphic rocks examined, glacial abrasion is favored in situat...

Mapping of the structural glaciology of Kongsvegen, Svalbard, reveals evidence for four main deformational structures. These are stratification, longitudinal foliation, thrusts and crevasse traces. These structures are considered in terms of their contribution to debris entrainment, transport and subsequent landform development. Stratification is associated with small amounts of supraglacial debris that has been folded with flow-parallel axes; longitudinal foliation in places incorporates basal glacial sediments along folds with flow-parallel axes; and thrusts transport basal debris to the glacier surface. Crevasse traces are not significant in terms of debris entrainment. The entrainment of basal debris along longitudinal foliation is not a universally recognised process. At Kongsvegen this process is attributed to the development of a transposition foliation, in combination with incorporation of debris-rich basal ice or soft basal sediment in the fold complex. Mapping of the landforms in the proglacial area shows that debris incorporated along longitudinal foliation is released as “foliation-parallel ridges” and that transverse ridges mark debris-bearing thrusts. The role of longitudinal foliation in landform development has never been documented in this manner. Although the preservation potential of such ridges may be limited, recognition of foliation-parallel ridges in the Pleistocene landform record has important implications for the interpretation of the dynamics of former ire masses.

Irregular mounds of glacial debris, commonly referred to as 9hummocky moraine9, until recently were linked to ice stagnation during rapid climatic amelioration. However, recent work in Scotland has demonstrated that some hummocky moraine, dating from the Younger Dryas event ( c. 10 000 years BP ), was the product of deposition at active ice margins. Observations at modern high–arctic glacier margins in Svalbard (76–80°N) indicate that some moraines of this type form under a dynamic glaciological regime, mainly by thrusting in active polythermal ice undergoing strong longitudinal compression. This situation is particularly common where there is a transition from warm–based ice in the interior of a glacier to cold–based ice at the margins or snout. From their morphological similarity (rectilinear slopes facing up–glacier and irregular downglacier faces), and apparent stacking of slabs of sediment of subglacial derivation, it is concluded that some assemblages of British moraines are also the product of thrusting. This process appears to be most dominant in polythermal glaciers, rather than in temperate glaciers. On this basis, it is tentatively suggested that the Younger Dryas in Britain was characterized by a climatic regime similar to that in Svalbard today (mean annual temperature − 5°C; 400–1000 mm precipitation), and that the associated glaciers may have been of polythermal character.

The formation of a moraine mound (hummocky moraine) complex at the Neoglacial limit of Pedersenbreen, Svalbard is discussed. The moraine mounds are composed for the most part of sheared basal diami...

Traditionally, geometrical ridge networks are interpreted as the product of the flow of subglacial sediment into open basal crevasses at the cessation of a glacier surge (‘crevasse-fill’ ridges). They are widely regarded as a characteristic landform of glacier surges. Understanding the range of processes by which these ridge networks form is therefore of importance in the recognition of palaeosurges within the landform record. The geometrical ridge network at the surge-type glacier Kongsvegen in Svalbard, does not form by crevasse filling. The networks consist of transverse and longitudinal ridges that can be seen forming at the current ice margin. The transverse ridges form as a result of the incorporation of basal debris along thrust planes within the ice. The thrusts were apparently formed during a glacier surge in 1948. Longitudinal ridges form through the meltout of elongated pods of debris, which on the glacier surface are subparallel to the ice foliation and pre-date the surge. This work adds to the range of landforms associated with glacier surges.

Many glaciers in Svalbard, which tend to be thermally complex with both warm and cold ice, produced complex ‘push moraines’ or ‘thrust-moraine complexes’ at the time of their maximum neoglacial advance, and during their subsequent recession. Uvěrsbreen, which nearly reaches the coast of northwest Spitsbergen, has a push moraine 50 m high, comprising gravel and sand of fluvial origin, and diamicton derived from basal ice, as well as thrust masses of dead ice. The push moraine is almost entirely a product of the tectonic processes, especially thrusting, that occurred in the snout of the glacier and in the frozen sediments immediately in Journal of Quaternary Science front. Thrusting is probably initiated where the glacier switches from a sliding mode to a state of being frozen to the bed. Thrusting in the foreland is an extension of the same processes that occur within the ice itself, and a sole thrust probably extends from the frozen sediment that underlies the base of the glacier near its snout. Thrusting results in subglacial sediment being uplifted to a high level within the glacier or even to the surface. Subsidiary near-horizontal thrusts parallel to the bedding plane link thrusts dipping up-glacier, and result in local thickening of individual subglacial sedimentary units. Gravels incorporated in this way retain their integrity but sands are folded, whereas uplifted debris-rich basal ice is intensely folded. The distinctive tectonic style of low-dip bedding in gravels, truncated by high-angle (30–40°) thrusts, and only localised folding in less competent material, differs from most descriptions of such ridges, but may be typical of many push moraines composed principally of fluvial material.

Fridtjovbreen is an actively surging tidewater glacier in western Spitsbergen, Svalbard. This paper presents observations made at the western flank of the glacier in July 1997, when the glacier front was still advancing rapidly and was characterised by steep lateral ice cliffs. The geomorphological consequences of the surge include the formation of push moraines from toppled ice blocks along this ice cliff and the development of debris-rich thrusts. There is also evidence of glaciotectonic deformation within deformed debris-rich thrusts. Thrusts are restricted to the lateral margins and are not seen in the terminal calving cliff. On its western flank, Fridtjovbreen is over-riding Sagabreen, a small-tributary glacier. Large facies variations in this area are a result of recycling by Fridtjovbreen of material originally transported as medial moraines on Sagabreen. There are few observations of landform development at actively surging glaciers in Svalbard. The Fridtjovbreen descriptions provide documentation for post-surge landform development. More observations are required at the margins of actively surging glaciers to determine how representative Fridtjovbreen is of a surge event.

The role of rock type in controlling downstream variation in clast parameters in non-jokulhlaup-affected, Oraefi sandar in Iceland was evaluated. Clast changes in the Svinafellsa are simple, but the effects of tributary sources complicate the clast parameter-distance relationships in the Morsardalur-Kjos system. The behavior of individual rock types must be studied to understand the changes. Both selective sorting and abrasion are taking place, and the relative importance of these processes is evaluated. The volcanic rocks are rounding relatively rapidly, with variation among individual rock types, but there are no significant changes in sphericity and clast form with distance. The compressive strength of the volcanic suite is variable, and significant weathering changes must be takin place during transport from rock face to distal sandur. The influence of such weathering changes on changes in clast parameters needs further research.

The form and stratigraphy of dominat pro glacial deposits is described and analysed for three distinct environments at a lobe of the inland ice: (i) an ice floored basin with terraced sediments at ...