Category: Nye Publikasjoner


Ny publikasjon i Elements

Eoghan Reeves (GEO), together with Jens Fiebig (Uni. Frankfurt), has written a review of the state of the art on abiotic organic molecules in Earth’s crust in the February issue of The Geochemical Society’s Elements magazine, available here:

http://elementsmagazine.org/past-issues/abiotic-hydrogen-and-hydrocarbons-in-planetary-lithospheres/

New publication in AGU100

The Arctic warms much faster than the global average. This amplified response can trigger feedbacks that affect the trajectory of future change. In areas formerly covered by ice, darker open water or rocks reflect less solar heat, enhancing warming. However, freshwater from melting ice may slow ocean circulation, leading to cooling. The climate impact of these mechanisms remain insufficiently understood, restricting efforts to predict future change. To reduce uncertainty, our research uses geological information from the most recent past period when the Arctic was warmer than the present, the Early Holocene, which lasted from 11,700 to 8,200 years ago. We analyzed fats from algae preserved in Svalbard lakes that yield information about past summer temperatures. Our findings show that the Early Holocene was characterized by the coldest and warmest extremes experienced since the last Ice Age. During peak warmth, summer temperatures were 7 °C warmer than today as more solar radiation and warm water reached the Arctic. However, Early Holocene warming was much slower than today. But warming was interrupted when freshwater pulses from melting Ice Sheets lowered temperatures. As we face a warmer Arctic with a melting Greenland Ice Sheet, our findings provide a rare window into the region’s future. Link to the paper itself. And a link to an outreach piece written by the Bjerknes Centre. Gratulerer til Willem og Jostein @ co. 🙂

8 nye artikler i Boreas – Geologiske arkiver fra dype innsjøer i de Polare Uralfjellene kaster nytt lys over istidsutviklingen i Russisk Arktis

Geologists investigating a long sediment core from the Polar Ural Mountains in Russia. Jan Mangerud (left), Haflidi Haflidason, John Inge Svendsen, Carl Regnell and Reidun Eldegård. Photo: Eva Bjørseth

Som del av forskningsprosjektet CHASE (Climate History along the Arctic Seaboard of Eurasia) holder vi på med å utforske miljø- og klimaendringene gjennom istider og mellomistider i Russisk Arktis. Vi har i den forbindelse hentet opp borekjerner fra innsjøer inne i de Polare Uralfjellene og vi har studert glasiasjonshistoren i omkringliggende områder. Noen av resultatene fra dette forskningsarbeidet ble nylig publisert i tidsskriftet Boreas, i et spesialhefte som omhandler arktiske innsjøer. Seismiske profiler profiler viser at fjellgrunnen under den dypeste sjøen ligger 110 m under dagens havoverflate og at bassenget er fyllt opp med 160 m med silt og leire. Vår tolkning av sediment-stratigrafien, som dels består av årslag (såkalte varv), er at denne tykke sedimentpakken er avsatt gjennom de siste 50-60,000 år og at det her rådet isfrie forhold under siste istidsglobale ismaksimum da hele Skandinavia var dekket av et mektig isdekke som nådde helt sør til Tyskland. Vi har altså fått et vindu inn i en periode som det har vært vanskelig å få innsikt i på grunn av manglende geologiske arkiver med så høy tidsoppløsning.  Undersøkelsene har så langt gitt oss helt ny innsikt i utviklingshistorien i denne delen av Arktis og viser at den klimatiske utviklingen her har vært nokså annerledes enn i områdene omkring Norskehavet og Nord Atlanteren. Gratulerer til John Inge & Co 🙂

Artikkel nr 1Artikkel nr 2Artikkel nr 3Artikkel nr 4Artikkel nr 5Artikkel nr 6Artikkel nr 7Artikkel nr 8

 

New publication in Science Advances with the title: “Earthquakes track subduction fluids from slab source to mantle wedge sink”


Authors: Felix Halpaap, Stéphane Rondenay, Alexander Perrin, Saskia Goes, Lars Ottemöller, Håkon Austrheim, Robert Shaw, Thomas Eeken. (alle fra UiB, Imperial College London, eller UiO)

Engelsk: The mechanism of earthquakes at depths greater than 50 km (in subduction zones) is a vigorously debated topic in the geosciences, but it is probable that such earthquakes are related to mineral reactions that liberate water into the system. In our new article, we show that there is indeed a direct relationship between the occurrence of earthquakes and the migration paths of fluids in the Hellenic and other subduction zones. Link to the artickle in Science Advances Congratulations!!

New publication: From subsurface to surface: a multidisciplinary approach to decode the landscape evolution of the karstic massif of Mt. Menikio, Macedonia, Northern Greece

Christos Pennos*, Stein-Erik Lauritzen, Konstantinos Vouvalidis, Patience Cowie, Sofia Pechlivanidou, Charikleia Gkarlaouni, Michael Styllas, Panagiotis Tsourlos, Antonios Mouratidis

We study the epiphreatic caves and the surficial karst landforms of Mt. Menikio to unravel the tectonic controls on the evolution of this karst landscape. We construct a chronological framework for the ancient water table positions using Th/U dating of speleothem samples. Our age constraints indicate that the water table has dropped by 35 m, to its current position, the last 77 ka ago. We show that the factors that controlled the relative position of the water table also controlled the uplift movement of Mt. Menikio and we estimate the relative maximum uplift rate since 77 ka ago to be 0.45 mmyr-1. Read the article here. Congratulations 🙂

 

“Nytt” enormt stort kontinent er oppdaget av forskere ved GEO

I perioden da dinosaurene kom på banen, trias-perioden, ble alle jordens kontinenter samlet sammen til ett superkontinent: Pangea. Det viser seg nå at en del av det nordlige Pangea er bevart under Barenshavet mellom Norge og Russland. -Vi oppdaget et enormt og svært gammelt elvedelta, forteller Tore Klausen, William Helland-Hansen og Bjørn Burr Nyberg. Ny artikkel i Geology med tittelen: The largest delta plain in Earth’s history. Gratulerer!! 🙂 Les også fra NewScientist, forskning.no, atlasobscura.com og Dagbladet.no

New publication in Geology: ‘Tipping the balance: Shifts in sediment production in an active rift setting’

The publication is by Sofia Pechlivanidou, Patience A. Cowie, Guillaume Duclaux, Casey W. Nixon, Robert L. Gawthorpe and Tristan Salles.

In this study we use a field-calibrated numerical model to explore the controls on landscape evolution across the Corinth rift, central Greece. We show that flexural tilting plays a key role in controlling the syn-rift sediment flux and, in a counterintuitive way, modifies the relationship between topographic relief and catchment-averaged erosion rates. Our results provide a new perspective on the origin and timing of sediment starvation relative to structural development in rifts.

Here is the link of our new publication in Geology. Congratulations 🙂

New publication has been rewarded by the 2018 choice of the “Basin Research” Journal’s Editor

Phd student Anneleen Geurts, supervised by Patience Cowie, Rob Gawthorpe and Ritske Huismans, has been rewarded for her article “Drainage integration and sediment dispersal in active continental rifts: A numerical modelling study of the central Italian Apennines” by the 2018 choice of the “Basin Research” journal’s Editor (https://onlinelibrary.wiley.com/page/journal/13652117/homepage/EditorsChoice.html). Written by Rebecca Bell, one of the journal’s Editors:

“The paper by Geurts and colleagues is commended on both scientific merit and presentation. The motivating question is impactful and clearly stated: What drives drainage integration in continental extensional systems? From there, the paper follows a very logical and impressive progression that tests also-clearly stated hypotheses. The methods and results show elegant integration of modeling and field observations. The significance of these results clearly extends beyond the Apennine study area, with global implications, as demonstrated in the discussion and conclusions. I have already tagged several of the figures for use in my basin analysis class this spring.”

Online version: https://onlinelibrary.wiley.com/doi/full/10.1111/bre.12289    Congratulations 🙂

 

 

Ny publikasjon: Reconstructing ice‐flow fields from streamlined subglacial bedforms: A kriging approach

Abstract
The orientation of several landforms, e.g. drumlins, flutes, crag‐and‐tails, and mega‐scale glacial lineations, records the direction of the overlying ice flow that created them. Populations of such features are used routinely to infer former ice‐flow patterns, which serve as the building blocks of reconstructions of palaeo ice‐sheet evolution. Currently, the conceptualisation of flow patterns from these flow‐direction records is done manually and qualitatively, so the extractable glaciological information is limited. We describe a kriging method (with Matlab code implementation) that calculates continuous fields of ice‐flow direction, convergence, and curvature from the flow‐direction records, and which yields quantitative results with uncertainty estimates. We test the method by application to the subglacial bedforms of the Tweed Valley Basin, UK. The results quantify the convergent flow pattern of the Tweed Palaeo‐Ice Stream in detail and pinpoint its former lateral shear margins and where ice flowed around basal bumps. Ice‐flow parameters retrieved by this method can enrich ice‐sheet reconstructions and investigations of subglacial till processes and bedform genesis. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. Read more here. Congratulations Anna 🙂

Nå har Gijs Henstra lansert boken om geologien på Ringerike

Boken er ute i bokhandelen men kan også kjøpes direkte på web-siden hans https://www.georike.com/ En kjempeflott bok – godt skrevet og illustrert for alle å lære i alle aldre  🙂
ringblad.no har også skrevet et stykke om han: https://www.ringblad.no/…/na-har-gijs-lanser…/s/5-45-686056…

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