A5060367204- Geology and Paleoclimatology Research
- Methane Hydrates and Related Phenomena
- Geochemistry and Elemental Analysis
- Geological formations and processes
- Hydrocarbon exploration and reservoir analysis
- Heavy metals in environment
- Groundwater and Isotope Geochemistry
- Paleontology and Stratigraphy of Fossils
- Mine drainage and remediation techniques
- Geological and Geophysical Studies
- Marine and coastal ecosystems
- Isotope Analysis in Ecology
- earthquake and tectonic studies
- Oceanographic and Atmospheric Processes
- Radioactive element chemistry and processing
- Geochemistry and Geologic Mapping
- Radioactive contamination and transfer
- Marine and environmental studies
- Underwater Acoustics Research
- Geomagnetism and Paleomagnetism Studies
- Geological and Geochemical Analysis
- Environmental Policies and Emissions
- Water Quality and Pollution Assessment
- Fluid Dynamics Simulations and Interactions
- Scientific Research and Discoveries
Geological Survey of Finland
2016-2025
University of Turku
2005-2010
Leibniz Institute for Baltic Sea Research
2010
ABSTRACT The growth and metal enrichment of ferromanganese minerals on the seafloor have intrigued many studies, yet role microbes in process has remained elusive. Here, we assessed microbial influence trace accumulation release concretions from Baltic Sea using 12‐week microcosm incubation experiments. We studied three concretion morphotypes: Crust, discoidal, spheroidal, with biotic abiotic treatments. samples were collected into bottles containing artificial brackish seawater Gulf...
Abstract. Iron (Fe) plays a key role in sedimentary diagenetic processes coastal systems, participating various redox reactions and influencing the burial of organic carbon. Large amounts Fe enter marine environment from boreal river catchments associated with dissolved matter (DOM) as colloidal oxyhydroxides, principally ferrihydrite. However, fate this pool estuarine sediments has not been extensively studied. Here we show that flocculation along salinity gradient an estuary northern...
Abstract. The anthropogenically forced expansion of coastal hypoxia is a major environmental problem affecting ecosystems and biogeochemical cycles throughout the world. Baltic Sea semi-enclosed shelf sea whose central deep basins have been highly prone to deoxygenation during its Holocene history, as shown previously by numerous paleoenvironmental studies. However, long-term data on past fluctuations in intensity zone are largely lacking, despite significant role these areas retaining...
Abstract. For millennia, humans have gravitated towards coastlines for their resource potential and as geopolitical centres global trade. A basic requirement ensuring water security coastal communities relies on a delicate balance between the supply demand of potable water. The interaction freshwater saltwater in settings is, therefore, complicated by both natural human-driven environmental changes at land–sea interface. In particular, ongoing sea-level rise, warming deoxygenation might...
Abstract. Submarine groundwater discharge (SGD) has been implicated as a significant source of nutrients and potentially harmful substances to the coastal sea. Although number reported SGD sites increased recently, their stratigraphical architecture aquifer geometry are rarely investigated in detail. This study analyses multifaceted dataset offshore seismic sub-bottom profiles, multibeam side-scan sonar images seafloor, radon measurements seawater groundwater, onshore ground-penetrating...
Natural and anthropogenic sediment mixing can significantly impact the fidelity of sedimentary records climate environmental variability human impact. This lead to incorrect interpretations previous state(s) a given ecosystem, its forcing mechanisms, future development. Here, natural processes (i.e. bioturbation, hydroturbation direct impact) are investigated in south-western Baltic Sea by sedimentological, ichnological, geochemical, radionuclide analyses assess their on time-marker profiles...
Sedimentary molybdenum (Mo) and uranium (U) enrichments are widely used to reconstruct changes in bottom water oxygen conditions aquatic environments. Until now, most studies using Mo U have focused on restricted suboxic-euxinic basins continental margin minimum zones (OMZs), leaving mildly reducing oxic (but eutrophic) coastal depositional environments vastly understudied. Currently, it is unknown: (1) what extent enrichment factors (Mo- U-EFs) can accurately sites experiencing mild...
Abstract This paper presents a model of late‐glacial and post‐glacial deposition for the late‐Neogene sedimentary succession Archipelago Sea in northern Baltic Sea. Four genetically related facies associations are described: (i) an ice‐proximal, acoustically stratified draped unit glaciolacustrine rhythmites; (ii) onlapping basin‐fill rotated rhythmite clasts transparent to chaotic matrix interpreted as debris‐flow deposits; (iii) ice‐distal, transparent, lacustrine, weakly laminated...
The bedrock of the northern halves North America and Europe is covered by Quaternary glacial deposits, forming a surficial overburden that relatively thin, nonlithified, lithologically variable on small scale (in terms grain-size, mineralogy, texture, fabric, structure, color), often has well-preserved depositional topography.These geologically unique characteristics fact was long considered to be only restricted economic value have caused it treated differently in geological research from...
The hadal zone, >6 km deep, remains one of the least understood ecosystems on Earth. We address bioturbational structures in sediment cores from depths exceeding 7.5 km, collected during IODP Expedition 386 Japan Trench. Micro-CT imaging 20 core sections allowed to identify biogenic sedimentary (incipient trace fossils) and their colonization successions within gravity flow deposits. Their frequency, consequent changes substrate consistency, oxygenation organic matter delivery...
Abstract: Holocene postglacial lacustrine clays in the northern Baltic Sea were studied for ichnofossils, petrography, and microscale elemental 34 S/ 32 S composition to understand impact of benthos-produced organic matrices on early diagenesis sediments. X-radiographs these display intense burrow mottling with discrete Palaeophycus , ‘Mycellia' rare Arenicolites . Small burrow-like irregularly shaped concretions separated from clays. The are composed framboidal pyrite poorly crystalline FeS...
Research Article| January 01, 2013 Iron isotope heterogeneity in pyrite fillings of Holocene worm burrows Joonas J. Virtasalo; Virtasalo * 1Geological Survey Finland, P.O. Box 96, FI-02151 Espoo, Finland *E-mails: joonas.virtasalo@gtk.fi; martin.whitehouse@nrm.se; aarno.kotilainen@gtk.fi. Search for other works by this author on: GSW Google Scholar Martin Whitehouse; Whitehouse 2Swedish Museum Natural History, 50007, SE-104 05 Stockholm, Sweden Aarno T. Kotilainen Author and Article...
The L ate P leistocene and H olocene glacial postglacial sediments of the Baltic Sea basin are conventionally classified into units according to so‐called B altic S ea stages: I ce ake, Y oldia ea, A ncylus ake itorina ea. stages have been identified in offshore sediment cores by fundamentally different criteria, precluding detailed comparisons amongst sea areas studies. Here, long reflection seismic pinger sub‐bottom profiles were studied from an area G ulf F inland, northern strata divided...
Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural over 6000 years ecosystem suggest that forecasted climate warming might enhance environmental problems Sea. proxy reveal increased sea surface temperatures expanded seafloor anoxia (in deep basins) during earlier warm phases, such as Medieval Climate Anomaly. Under future IPCC scenarios global warming, there is likely no improvement bottom water conditions...