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Supplementary Data for: Glacial erosion and Quaternary landscape development of the Eurasian Arctic
No full textThis dataset contains a high-resolution palaeo-topography reconstruction of the Eurasian Arctic through the Quaternary (Article abstract: Multiple ice age cycles spanning the last three million years have fundamentally transformed the Arctic landscape. The cadence, intensity and pattern of this glacial modification underpin the stability of Arctic geosystems over geologic time scales, including its hydrology, circulation patterns, slope stability, hydrocarbon fluid flow, geochemical/sediment cycling and nutrient supply. The Barents Shelf provides a unique arena to investigate long-term landscape evolution as it has undergone significant glacial modification during the Quaternary and has an extensive stratigraphic data repository motivated by decades of hydrocarbon seismic and well exploration. Here, we assimilate new geological datasets with ice sheet erosion modelling to incrementally reconstruct the geomorphic evolution of the Eurasian Arctic domain over each of the 47 glaciations since the intensification of Northern Hemisphere glaciation ~2.74 Ma. We utilise this time-transgressive framework to review hypotheses regarding the heterogenous development of the Barents Shelf and the timing of key topographic reconfiguration episodes. Our results demonstrate that up to 2.6 km of bedrock was glacially removed to the shelf margins, and though the mean rate of erosion declines over the Quaternary, the efficacy of glacial erosion has a more complex timeline. Initially, erosion was highly effective as large expanses of the Eurasian Arctic switched from subaerial exposure to marine conditions around 2 Ma ago. Thereafter, erosional efficacy decreased as the landscape desensitized to successive glaciations but, after 1 Ma, it increased as a dynamic, marine-based ice sheet drained by ice streams expanded, selectively eroding large outlet troughs to the shelf edge. Critically for Arctic climate, at ~0.69 Ma this episode of enhanced preferential erosion opened up the Barents Seaway establishing a new circulation pathway between the Atlantic and Arctic Oceans. Our 4D landscape reconstruction provides key boundary conditions for paleoclimate models and establishes a new framework for assessing the profound impact of late-Cenozoic glaciation on the Eurasian Arctic landscape.</p
Supporting Data for: Holocene changes in the position of the Southern Hemisphere Westerlies recorded by long-distance transport of pollen to the Kerguelen Islands
No full textThis repository contains a sedimentological databundle consisting of micro X-Ray Fluorescence (μXRF), Computed Tomography (CT), Magnetic susceptibility (MS), Dry bulk density (DBD), and Loss-on-ignition (LOI) measurements associated with the publication: Holocene changes in the position of the Southern Hemisphere Westerlies recorded by long-distance transport of pollen to the Kerguelen Islands, published in Quaternary Science Reviews. The μXRF, CT, MS, DBD, and LOI measurements derive from the 357.5 cm long sediment core L50319, collected from the Kerguelen Islands. The site, the informally named Lake 5 (49.14°S, 69.09°E, ∼130 m above sea level), was cored using a gravity corer and modified piston corer as part of the joined NFR grant funded project SOUTHSPHERE (project number 267719) and Institut Polaire Français (IPEV) funded project PALAS2 ('PAleoclimate from LAke Sediments on Kerguelen Archipelago 2'; project number: 1094).The Southern Hemisphere Westerlies (SHW) are a vital part of the Southern Hemisphere's coupled ocean-atmosphere system and play an important role in the global climate system. The SHW affect the upwelling of carbon-rich deep water and exchange of CO2 from the ocean to the atmosphere by driving the Antarctic Circumpolar Current. On seasonal to millennial timescales, changes in the strength and position of the SHW are associated with temperature and precipitation changes throughout the extratropical Southern Hemisphere. Understanding the behaviour of the SHW under different background climate states is important for anticipating its future behaviour and remains a subject of ongoing research. Terrestrial paleoclimate records from lake sediments are valuable for reconstructing past atmospheric change and records from the handful of sub-Antarctic islands provide the opportunity to develop datasets to document spatio-temporal patterns of long-term SHW behaviour. Here, we generate palynological, microcharcoal, and sedimentological reconstructions (including CT imagery, μXRF analysis, magnetic susceptibility, and loss-on-ignition) on lake sediments from the Kerguelen Islands (49°S) to constrain variability in Holocene vegetation, climate, and atmospheric circulation (SHW position). Due to the influence of the SHW on the Kerguelen Islands, the influx of long-distance transported (LDT) pollen and microcharcoal from southern Africa serve as proxies for the meridional position of the SHW. In contrast with the stable conditions that prevailed on the Kerguelen Islands over the past 8,600 cal yr BP, our findings reveal a highly dynamic Early Holocene period. Consistent with local palynological evidence of warmer conditions, a high influx of LDT pollen and charcoal from southern Africa suggest that the SHW core belt was located further south of the Kerguelen Islands during this time. Comparison against paleoclimate records from the surrounding region and beyond suggests that the inferred changes might be explained by changes to our planet's interhemispheric thermal gradient, triggered by North Atlantic cooling in response to melting of the last remnants of the Laurentide Ice Sheet.</p
Extended data for: Impact of sub-basalt thrust systems on the Faroe continental shelf for the late Paleoproterozoic–Cenozoic tectonic evolution of the margin
No full textHigh-resolution version of the seismic reflection data off the Faroe Islands from TGS presented in "Impact of sub-basalt thrust systems on the Faroe continental shelf for the late Paleoproterozoic–Cenozoic tectonic evolution of the margin".
The data were acquired by Western Geophysical in 1994-1995 and reprocessed by TGS between April 2011 and January 2012 (Nicholson, 2012; internal reprocessing report accessible upon contacting TGS).
Nicholson, A.: Final Report Seismic Data Re-processing Offshore Faroes, April 2011-January 2012, Project No. 624, Project Code OF9495RE11, 2012.Extended data for "Impact of sub-basalt thrust systems on the Faroe continental shelf for the late Paleoproterozoic–Cenozoic tectonic evolution of the margin". The dataset includes the following:
-Figure_2a: Interpreted (up) and uninterpreted (down) Figure 2a: NNE–SSW-trending seismic transect west of the Faroe Islands showing the occurrence of major NNE-dipping, top-SSW thrust systems below Cenozoic lavas off the Faroe Islands. The thrust systems consist of major mylonitic shear surfaces (red lines) and of tightly folded bedding or foliation surfaces (yellow lines). Relatively small (kilometer to hundreds of meters wide) features of interest include asymmetric (up to isoclinal recumbent) folds, duplexes, and antiformal thrust stacks. The vergence of asymmetric fold structures (and mylonitic shear surfaces) is opposite on either side of major ridges and highs, e.g., at Wyville–Thomson Ridge, suggesting limited amounts of movement. There are Z-shaped reflections in the lower part of the Suðurøy and West Faroe fault zones suggesting extensional reactivation of the fault zones.
-Figure_2b: Interpreted (up) and uninterpreted (down) Figure 2b: NE–SW-trending seismic transects showing the continuation of the top-SSW Wyville–Thomson fault zone at Wyville–Thomson Ridge.
-Figure_2c: Interpreted (up) and uninterpreted (down) Figure 2c: NE–SW-trending seismic transects showing the continuation of the top-SSW Wyville–Thomson fault zone at Wyville–Thomson Ridge.
-Figure_2d: Interpreted (up) and uninterpreted (down) Figure 2d: NE–SW-trending seismic transects showing the continuation of the top-SSW Wyville–Thomson fault zone at Wyville–Thomson Ridge.
-Figure_2e: Interpreted (up) and uninterpreted (down) Figure 2e: WNW–ESE-trending seismic section along the Wyville–Thomson Ridge showing tens of kilometers wide, open, NNE–SSW-striking macrofolds deforming the top-SSW Wyville–Thomson fault zone. The opposite sense of shear is indicated by asymmetric folds and minor brittle thrusts on either limbs of the macrofolds, which suggests limited amount of tectonic displacement. In the northwest, the section displays gently northwest-dipping, moderate-amplitude reflections (blue lines), curving-downward reflections (black lines), and southeast-dipping disruption surfaces (black lines) interpreted respectively as SDRs, saucer-shaped sills, and dykes and sills. The later crosscut the folded Wyville–Thomson fault zone. The Wyville–Thomson fault zone and related asymmetric folds extend below and northwest of the SDRs suggesting that the Iceland–Faroe Ridge consists (at least partly) of continental crust.
-Figure_2f: Interpreted (up) and uninterpreted (down) Figure 2f: ENE–WSW-trending seismic section at the Munkagrunnur Ridge showing asymmetric folds indicating top-east kinematics along the Munkagrunnur fault zone. The Z-shaped reflections suggest extensional reworking of the fault zone.
-Figure_2g: Interpreted (up) and uninterpreted (down) Figure 2g: NE–SW-trending seismic transect at Munkagrunnur Ridge showing the dominance of top-NNE kinematic indicators (e.g., NNE-verging folds and top-NNE minor brittle thrusts) along the Munkagrunnur fault zone.
-Figure_2h: Interpreted (up) and uninterpreted (down) Figure 2h: NW–SE-trending transect along the Munkagrunnur Ridge showing the reworking of the Munkagrunnur fault zone by a tens of kilometers wide, NNE–SSW-striking, SSW-plunging macrofold with opposite sense of shear on either flanks.
-Figure_2i: Interpreted (up) and uninterpreted (down) Figure 2i: Folded portion of the West Faroe fault zone that was overprinted by a top-northwest Caledonian thrust. The listric, post-Caledonian, brittle, normal fault, which offsets the Top-basement reflection by ca. 1 second (TWT) merges with the top-northwest thrust at depth suggesting it formed along preexisting zones of weakness in the crust.Abstract of the revised, accepted version of the related manuscript "Impact of sub-basalt thrust systems on the Faroe continental shelf for the late Paleoproterozoic–Cenozoic tectonic evolution of the margin".
Background
The Faroe margin in the northeastern Atlantic is segmented by margin-orthogonal, WNW–ESE-striking lineaments extending several hundred kilometers out to the continent–ocean transition. Despite several earlier studies speculating that these features are the product of reactivation of pre-Cenozoic basement-seated structures at depth, the thick Cenozoic volcano-sedimentary sequences deposited along the margin mask the underburden, thus rendering the identification and interpretation of such structures and resolving the pre-Cenozoic history of the area challenging. The present study documents for the first time the existence of margin-orthogonal basement-seated thrust systems and describes their detailed geometry, kinematics, and tectonic evolution.
Methods
We interpreted basement-seated tectonic structures on seismic reflection data from TGS on the Faroe Platform and the Wyville–Thomson and Munkagrunnur ridges using the newly established seismic facies of major thrust systems.
Results
The data show that the Wyville–Thomson Ridge, Munkagrunnur Ridge, and Faroe Platform are cored by WNW–ESE-striking thrust systems hundreds of kilometers long and 30–50 km wide, showing dominantly top-SSW kinematics. The thrusts were reworked into NE–SW-striking folds during the Caledonian Orogeny and controlled the formation of Caledonian thrusts, which in turn controlled the formation of post-Caledonian faults. The pre-Caledonian nature of the WNW–ESE-striking thrusts and their geometry and kinematics suggest a relationship with late Paleoproterozoic Laxfordian shear zones onshore northern Scotland and the continuation of the coeval Nagssugtoqidian Orogen in southeastern Greenland, the Ammassalik Belt. The thrust systems also align with the Tornquist Zone in eastern Europe and the North Sea, thus suggesting either that they controlled the formation of the Tornquist Zone or a possibly much longer (Paleoproterozoic?) tectonic history for the Tornquist Zone.
Conclusions
The Faroe Island margin is crosscut by late Paleoproterozoic Laxfordian–Nagssugtoqidian thrust systems, which controlled further tectonic development of the margin.</p
Replication Data for: Risk-based path planning for preventing collisions and groundings of maritime autonomous surface ships
No full textField trials on risk-based path planning with an autonomous surface vehicle.Two field trial experiments were performed to test and demonstrate risk-based path planning with KPRA, a method for dynamic probabilistic risk assessment, and risk evaluation on an autonomous surface vehicle (ASV) from Maritime Robotics. The main objective was to observe the effect of KPRA on an ASV’s behavior, compared to its nominal behavior, in an uncontrolled and uncertain environment.
The first experiment tested KPRA’s effect on the ASV navigating open waters during a crossing encounter with another vessel. The second experiment increased the environmental complexity and tested the method in a crossing encounter near an island. Both experiments yielded datasets, called "open_waters" and "near_land" respectively, containing data on the ASV's state (e.g., position, speed and heading), the other vessel's state, and the explored planning state-space (i.e., the states considered by KPRA when searching for an adequate path), among others.
Both experiments were performed in areas around Munkholmen island in Trondheim, Norway. The island is a tourist spot in Trondheim, frequently approached by recreational vessels and kayaks, so the risks of collision and grounding are present. In both experiments, the main goal for the ASV was to autonomously navigate near the island while performing risk assessment and avoiding undesired consequences - in this case, collision with other ships and powered groundings
Background data for: Probabilistic variability in clausal verb complementation in World Englishes
No full textThis dataset contains tabular files recording occurrences of the verb REGRET in the GloWbE corpus. Tokens were retrieved using the online interface (https://www.english-corpora.org/glowbe/) and manually annotated for several syntactic and semantic variables. See ReadMe file for more details. Related publication: Romasanta, Raquel P. 2023. Probabilistic variability in clausal verb complementation in World Englishes. Berlin: Peter Lang
3DMSL - 3D Mitochondria Shape Library for Optical Microscopy
No full textDataset description:
This dataset contains individual 3D mitochondria extracted from 3D electron microscopy images in different 3D shape representation formats of meshes, point clouds and implicit shapes. The dataset also includes synthetic microscope images of these shapes.Article abstract:
With more deep learning solutions being developed for fluorescence microscopy image analysis, there is increasing demand for annotated ground truth datasets for training supervised methods. However, obtaining these annotations is a laborious and expensive endeavor. To address this problem for microscope analysis of cell organelles, we release 3DMSL, a database of 3D shapes of mitochondria. 3DMSL utilizes high-resolution Electron Microscopy data as the source for creating the extensive database. Utilizing a physics-based simulator, 3DMSL allows the creation of large fluorescence microscope image datasets with 3D ground truths that can be used to train deep learning models for 3D shape reconstruction, microscope-microscope style transfer, 2D and 3D segmentation etc. We demonstrate this using a variety of example application in this paper. 3DMSL contains more than 27K instances of diverse mitochondria shapes in different 3D shape representation formats of , meshes, point clouds and implicit shapes.</p
GNSS Total Electron Content Data (60 s) at Bjørnøya in 2023
No full textThis data set contains Total Electron Content data at 60 seconds time resolution from Bjørnøya, Svalbard.
The measurements were collected by the University of Bergen using a NovAtel GPStation-6 global navigation satellite system receiver. The measurements include signals from GPS, GLONASS, and GALILEO at different frequencies. These data are used for research on space weather disturbances in the polar ionosphere.
A detailed description of the data structure and format is gathered in the documentation data set: Oksavik, Kjellmar, 2020, "Documentation of GNSS Total Electron Content and Scintillation Data (60 s) at Svalbard", DataverseNO, https://doi.org/10.18710/EA5BYX
This data set is part of a larger collection: Oksavik, Kjellmar, 2020. "The University of Bergen Global Navigation Satellite System Data Collection". DataverseNO. https://doi.org/10.18710/AJ4S-X394.
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Replication Data for: Quantifying Uncertainty in Foraminifera Classification: How Deep Learning Methods Compare to Human Experts
No full textThis dataset contains PNG images of individual foraminifera and sediment grains. The dataset contains a set of training images, and a set of test images. Each of the sets contains four subfolders for each of the four classes in the dataset. The four classes are: A (Benthic Agglutinated foraminifera), B (Benthic Calcareous foraminifera), P (Planktic foraminifera), and S (Sediment grains). The training dataset consists of 258 from class A, 380 from class B, 332 from class P, and 341 from class S (1311 in total). The test dataset consists of 65 images from each class (260 in total). The resolution varies from image to image.
The photos were produced by capturing images using a 51 megapixel Canon EOS 5DS R mounted on a Leica M420 stereo microscope. A Leica cls 150x twin gooseneck combination light was used for lighting at fixed lumen. The photographed specimens were handpicked, allowing a very high degree of certainty for the labeling.
All photographed materials (foraminifera and sediment) were extracted from sediment cores retrieved at water depth ranging from about 100–700m from both fjord and shelf settings in the Arctic Barents Sea region
Replication data for: Phenotypic plasticity and thermal efficiency of temperature responses in two conspecific springtail populations from contrasting climates
No full textIn the present dataset, we focused on a soil microarthropod species abundant across the Northern Hemisphere, Folsomia quadrioculata (Collembola), with previously-known effects of macroclimate. We selected an arctic and a temperate population from areas with contrasting climates (highly stochastic and preictable, respectively) and compared them for thermal plasticity and thermal efficiency in growth, development, fecundity, and survival across four temperatures (10, 15, 20 and 25°C) for a major part of their life cycle. We intended to understand the mechanisms by which temperature drives the evolution of life history strategies. We found that the temperate population maximized performance at 10–15°C, whereas the arctic population maintained its thermal efficiency across a wider temperature range (10–20°C). Thermal plasticity varied in a trait-specific manner, but when considered together with differences in thermal efficiency, indicated that stochasticity in temperature conditions may be important in shaping the life history strategies. Analyses of these data reveal the importance of a "whole-organism approach" and physiological time considerations in clarifying thermal adaptation and understanding plausible climate-trait links underlying organismal responses to global climate change
Replication Data for: Alea iacta est. Insights from corpus semantics into the diachrony of the Latin passive
No full textDataset includes annotated corpus data from Latin texts from the 3rd c. BCE until the 10th c. CE. Attestations of forms of both the original construction ('PP-BE.inf.', e.g. 'cantatus est') and the innovation ('PP-BE.perf.', e.g. 'cantatus fuit') for the expression of the passive (taken together with forms of deponent verbs into 'nonactive') of perfectum stem tenses were extracted from major online corpora (331.131 data points); a random sample (n = 383) of data points of PP-BE.inf. that represents all text types and time periods as evenly as possible was then subjected to a close-reading analysis in order to ascertain the attestation rate of meanings for which it competed with the innovation PP-BE.perf. (specialized in ANTERIORITY) and the present tense (specialized in present events or situations). Only the data points that were annotated in full in this second phase are included in the current dataset. For the data points examined in the first phase, only the formal categories in the list below were annotated to the extent that these annotations are not subject to interpretation