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Recent acceleration of rock glaciers is well recognized in the European Alps, but similar behavior is hardly documented elsewhere. Also, the controlling factors are not fully understood. Here we provide evidence for acceleration of a rock glacier complex in northern Norway, from 62 years of remote sensing data. Average annual horizontal velocity measured by aerial feature tracking increased from ~0.5 myr−1 (1954–1977) to ~3.6 myr−1 (2006–2014). Measured by satellite synthetic aperture radar offset‐tracking, averages increased from ~4.9 to ~9.8 myr−1 (2009–2016) and maximum velocities from ~12 to ~69 myr−1. Kinematic analysis reveals different spatial‐temporal trends in the upper and the lower parts of the rock glacier complex, suggesting progressive detachment of the faster front. We suggest that permafrost warming, topographic controls, and increased water access to deeper permafrost layers and internal shear zones can explain the kinematic behavior.

It is well known that satellite radar interferometry (InSAR) is capable of measuring surface displacement with a typical accuracy on the order of millimeters to centimeters. However, when the true deformation vector differs from the satellite line-of-sight (LOS), the sensitivity decreases and interpretation of InSAR deformation measurements becomes challenging. By combining displacement data from extensive ascending and descending TerraSAR-X datasets collected during the summer seasons of 2009-2014, we estimate two-dimensional (2D) InSAR surface displacement. Displacement data are decomposed into vertical and west/east deformation, dip and combined deformation vector, and validated using Global Navigation Satellite System (GNSS) data. We use the decomposed dataset to visualize variations in surface velocity and direction on unstable slopes in a periglacial environment with sporadic permafrost in northern Norway. By identifying areas with uplift and subsidence, and detecting velocity changes (downslope acceleration/deceleration) and related areas of extension and compression, we are able to explain driving and controlling mechanisms and geomorphology in two rockslides and one area with solifluction landforms.

Lithofacies characteristics and depositional geometry of a sandy, prograding delta deposited as part of the Holocene valley‐fill stratigraphy in the Målselv valley, northern Norway, were examined using morpho‐sedimentary mapping, facies analysis of sediments in exposed sections, auger drilling and ground penetrating radar survey. Various lithofacies types record a broad range of depositional processes within an overall coarsening‐upward succession comprising a lowermost prodelta/bottomset unit, an intermediate delta slope/foreset unit containing steeply dipping clinoforms and an uppermost delta plain/topset unit. Bottomset lithofacies typically comprise sand‐silt couplets (tidal rhythmites), bioturbated sands and silts, and flaser and lenticular bedding. These sediments were deposited from suspension fall‐out, partly controlled by tidal currents and fluvial effluent processes. Delta foreset lithofacies comprise massive, inverse graded and normal graded beds deposited by gravity‐driven processes (mainly cohesionless debris flows and turbidity currents) and suspension fall‐out. In places, delta foreset beds show tidal rhythmicity and individual beds can be followed downslope into bottomset beds. Delta plain facies show an upward‐fining succession with trough cross‐beds at the base, followed by planar, laminated and massive beds indicative of a bedload dominated river/distributary system. This study presents a model of deltaic development that can be described with reference to three styles within a continuum related primarily to water depth within a basin of variable geometry: (i) bypass; (ii) shoal‐water; and (iii) deep‐water deltas. Bypass and deep‐water deltas can be considered as end members, whereas shoal‐water deltas are an intermediate type. The bypass delta is characterized by rapid progradation and an absence of delta slope sediments and low basin floor aggradation due to low accommodation space. The shoal‐water delta is characterized by rapid progradation, a short delta slope dominated by gravity‐flow processes and a prodelta area characterized by rapid sea‐floor aggradation due to intense suspension fallout of sandy material. Using tidal rhythmites as time‐markers, a progradation rate of up to 11 m year−1 has been recorded. The deep‐water delta is characterized by a relatively long delta slope dominated by gravity flows, moderate suspension fall‐out and slow sea‐floor aggradation in the prodelta area.

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(March): Isolation basin stratigraphy andHolocene relative sea-level change at the Norwegian-Russian border north of Nikel, northwest Russia. Boreas, Vol. 28. pp. 146166. Oslo. ISSN 0300-9483. The marine-lacustrine transition (isolation contact) in sediment cores from eight lake basins situated 13.5-72 m a.s.1.. in the Nonvegian-Russian border area north of Nikel, northwest Russia, was identified based on Lithological and diatom analysis, radiocarbon dated, and used to construct a relative sea-level (RSL) curve for the Holocene. All the lakes except one (interpreted as having an unconformable slumped transition) show a regressive 1-11-111 (marine-transitional-lacustrine) facies succession, indicating a postglacial history of continuous emergence. The RSL curve shows rapid emergence between 10000 and 8000 BP, very slow emergence between 7000 ahd 5000 BP, increased rate of emergence between 4500 and 4000 BP, and a moderate rate of emergence after 3500 BP. The low rate of emergence around 6000 BP correlates with the Tapes transgression of more coastal regions, but corresponding sea level, at 25-26 ma. present s.l., lies 5-10 m lower than the elevation predicted based on existing isobase maps for the region. The discrepancy suggests a need for further work in order to more rigorously define and map the Tapes transgression and associated shoreline complex in the northern Fennoscandian-Kola region.

'Asynchronous response of marine-terminating outlet glaciers during deglaciation of the Fennoscandian Ice Sheet. ', Geology., 42 (5). pp. 455-458. Further information on publisher's website:http://dx.doi.org/10.1130/G35299.1Publisher's copyright statement:Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Abstract: Recent studies have highlighted the dynamic behavior of marine-terminating outlet glaciers over decadal time-scales, linked to both atmospheric and oceanic warming. This helps explain episodes of near-synchronous flow acceleration, thinning and retreat, but non-climatic factors such as subglacial overdeepenings can also induce rapid recession. There is support for these topographic controls on glacier retreat, but there are few long-term records to assess their significance across a population of glaciers over millennial time-scales. Here, we present retreat chronologies alongside topographic data for eight major outlet glaciers that experienced similar climatic forcing during deglaciation of the Fennoscandian Ice Sheet (ca. 18-10 cal. kyr B.P.). Retreat rates averaged over several millennia (~30 m a-1) are less than half those recently observed on modern-day outlet glaciers (>100 m a-1), but deglaciation was punctuated by episodes of more rapid retreat (up to ~150 m a-1) and re-advances. Significantly, phases of rapid retreat were not synchronous between glaciers and most occurred irrespective of any obvious atmospheric warming. We interpret this to reflect the complex interplay between external forcing and both topographic (e.g., bathymetry, width) and glaciological factors (e.g., ice catchments) that evolve through time, but conclude that basal over-deepenings in wide fjords induce episodes of rapid retreat (>100 m a-1), further exacerbated by their greater susceptibility to oceanic warming. This complicates attempts to predict the centennial-scale trajectory of outlet glaciers and suggests that modeling the interaction between neighboring catchments and the accurate description of subglacial topography beneath them is a priority for future work.Response to Reviewers: See attached cover letter and response to reviewer comments Powered by Editorial Manager® and ProduXion Manager® from Aries Systems CorporationPublisher: GSA Journal: GEOL: Geology Article ID: G35299 Recent studies have highlighted the dynamic behavior of marine-terminating 11 outlet glaciers over decadal time-scales, linked to both atmospheric and oceanic warming. 12This helps explain episodes of near-synchronous flow acc...