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The 17 June 2017 rock avalanche in the Karrat Fjord, West Greenland, caused a tsunami that flooded the nearby village of Nuugaatsiaq and killed four people. The disaster was entirely unexpected since no previous records of large rock slope failures were known in the region, and it highlighted the need for better knowledge of potentially hazardous rock slopes in remote Arctic regions. The aim of the paper is to explore our ability to detect and locate unstable rock slopes in remote Arctic regions with difficult access. We test this by examining the case of the 17 June 2017 Karrat rock avalanche. The workflow we apply is based on a multidisciplinary analysis of freely available data comprising seismological records, Sentinel-1 spaceborne synthetic-aperture radar (SAR) data, and Landsat and Sentinel-2 optical satellite imagery, ground-truthed with limited fieldwork. Using this workflow enables us to reconstruct a timeline of rock slope failures on the coastal slope here collectively termed the Karrat Landslide Complex. Our analyses show that at least three recent rock avalanches occurred in the Karrat Landslide Complex: Karrat 2009, Karrat 2016, and Karrat 2017. The latter is the source of the abovementioned tsunami, whereas the first two are described here in detail for the first time. All three are interpreted as having initiated as dip-slope failures. In addition to the recent rock avalanches, older rock avalanche deposits are observed, demonstrating older (Holocene) periods of activity. Furthermore, three larger unstable rock slopes that may pose a future hazard are described. A number of non-tectonic seismic events confined to the area are interpreted as recording rock slope failures. The structural setting of the Karrat Landslide Complex, namely dip slope, is probably the main conditioning factor for the past and present activity, and, based on the temporal distribution of events in the area, we speculate that the possible trigger for rock slope failure

The Greenland landmass preserves ∼4 billion years of tectonic history, but much of the continent is inaccessible to geological study due to the extensive inland ice cap. We map out, for the first time, the 3-D crustal structure of Greenland and the NW Atlantic ocean, using Rayleigh wave anisotropic group velocity tomography, in the period range 10–80 s, from regional earthquakes and the ongoing GLATIS/GLISN seismograph networks. 1-D inversion gives a pseudo-3-D model of shear wave velocity structure to depths of ∼100 km with a horizontal resolution of ∼200 km. Crustal thickness across mainland Greenland ranges from ∼25 km to over 50 km, and the velocity structure shows considerable heterogeneity. The large sedimentary basins on the continental shelf are clearly visible as low velocities in the upper ∼5–15 km. Within the upper continental basement, velocities are systematically lower in northern Greenland than in the south, and exhibit a broadly NW–SE trend. The thinning of the crust at the continental margins is also clearly imaged. Upper-mantle velocities show a clear distinction between typical fast cratonic lithosphere (Vs ≥4.6 km s−1) beneath Greenland and its NE margin and anomalously slow oceanic mantle (Vs ∼4.3–4.4 km s−1) beneath the NW Atlantic. We do not observe any sign of pervasive lithospheric modification across Greenland in the regions associated with the presumed Iceland hotspot track, though the average crustal velocity in this region is higher than that of areas to the north and south. Crustal anisotropy beneath Greenland is strong and complex, likely reflecting numerous episodes of tectonic deformation. Beneath the North Atlantic and Baffin Bay, the dominant anisotropy directions are perpendicular to the active and extinct spreading centres. Anisotropy in the subcontinental lithosphere is weaker than that of the crust, but still significant, consistent with cratonic lithosphere worldwide.

AIM: To understand the lived experience of body image in young women after obesity surgery.BACKGROUND: Quantitative studies have documented that health-related quality of life and body image are improved after bariatric surgery, probably due to significant weight loss. Female obesity surgery candidates are likely to be motivated by dissatisfaction regarding physical appearance. However, little is known about the experience of the individual woman, leaving little understanding of the association between bariatric surgery and changes in health-related quality of life and body image.DESIGN: A qualitative descriptive phenomenological study.METHODS: Data were collected over 4 months during 2010. Selection for interview was carried out through purposeful sampling. The participants were five young women who underwent bariatric surgery (range: 1-12 months). In-depth, semi-structured interviews were analysed by systematic text condensation influenced by Giorgi's phenomenological method and supplemented by elements from narrative analysis.FINDINGS: The analysis revealed three concepts: solution to an unbearable problem, learning new boundaries and hopes of normalization. These revelatory concepts were synthesized into one major theme: on the edge of control, that is describing these women's feelings of being on the edge of balance between control and loss of control.CONCLUSION: Perception of control may be an essential aspect of body image and the key to understanding these young women's feelings of empowerment and quality of life through body control postbariatric surgery. Future studies should focus on how body control is an essential aspect of body image, which may contribute to long-term weight loss maintenance and improve quality of life.

Grønland er formet af voldsomme geologiske processer, som har sat deres præg på landskabet gennem flere milliarder år. Nu om stunderer de tektoniske processer i området mere fredelige, og rønland ligger trygt og godt på den Nordamerikanske plade.

Med knap 12 minutters mellemrum blev Asien ramt af to kraftige jordskælv d. 10. august 2009. Først gik det ud over Andamanerne i det Indiske Ocean, som blev ramt af et jordskælv der målte 7,6 på Richterskalaen. Kort tid efter var det Japans tur, da et jordskælv på 6,4 satte både hav og jord i bevægelse ud for det sydlige Honshu.

Det er en klassiker. Et stort jordskælv sender huse i grus, mange mennesker mister livet, og endnu flere bliver hjemløse. Katastrofen er omfattende og tragedien ubærlig. Frem af kaos dukker en person, som hævder at have forudsagt jordskælvet, og hvis advarsler er blevet ignoreret af myndigheder og borgere. Hvis bare vi havde lyttet, kunne menneskeliv være sparet.

En helt almindelig søvnig vintermorgen, d.16. december 2008, blev tusindvis af danskere vækket ca. kl. 6.20 af de uvante rystelser fra et jordskælv. Huse knagede, ting og sager raslede, senge svajede og uhyggelige lyde hørtes fra undergrunden. Nogle steder var oplevelsen så intens, at forskrækkede mennesker løb udenfor – ganske som man bør, hvis man pludselig befinder sig midt i et kraftigt jordskælv.

Island vokser støt og roligt med knap 2 cm om året. Det sker i takt med, at den Nordamerikanske plade og den Eurasiske plade driver i hver sin retning og dermed giver plads til ny skorpe i Islands vulkanske riftzoner. Islands vokseværk kan mærkes som små jordskælv, der dagligt ryster øen.

Jordens mest spektakulære topografi findes i Asien, hvor høje bjergtinder knejser mod himlen, skabt i sammenstødet mellem Indien og Eurasien over de seneste 50 millioner år. Topografi en vedligeholdes løbende af den aktive pladetektonik i området. Den Indiske plade presser sig ubønhørligt nordpå med 4-5 cm om året, og den Eurasiske plade lader sig ikke uden videre flytte, så undergrunden flænses jævnligt af voldsomme jordskælv, når klipperne må give efter for presset.

Inden for en måned ramte flere kraftige jordskælv henholdsvis det centrale Peru og kysten ud for det centrale Sumatra med tab af menneskeliv til følge - er der en sammenhæng mellem jordskælvene, eller er det blot helt tilfældigt?

Sumatra-jordskælvet udløste en næsten ubegribelig menneskelig katastrofe i landene omkring Det Indiske Ocean med tæt på 300.000 omkomne. Langt de fleste blev ofre for den tsunami, som jordskælvet satte i gang. Jordskælvet er også opsigtsvækkende rent videnskabeligt på grund af sin voldsomhed og de naturvidenskabelige fænomener der fulgte med; den enorme brudzone, de store forskydninger, tsunamien og de kraftige rystelser, som satte hele jordkloden i svingninger.

Jorden svinger stadig efter det store jordskælv vest for det nordlige Sumatra d. 26. december 2004. Jordskælvet, som netop er blevet opjusteret til 9,3 på Richterskalaen, er det største siden jordskælvet ud for Chiles kyst i 1960, som målte 9,5.