Browsing by Subject "1171 Geotieteet"

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  • Hilander, Markus (2016)
  • Todorovic, Sara; Rekola, Hanna; Muukkonen, Petteri; Bernelius, Venla (Helsingin kaupunki, 2020)
    Helsingin kaupungin pelastuslaitoksen julkaisuja
  • Heinonen, Jussi S.; Luttinen, Arto V. (2013)
    Our two-person “flood basalt task force” (authors Arto Luttinen and Jussi Heinonen) of the Finnish Museum of Natural History (LUOMUS) spent three weeks in Mozambican countryside collecting samples of the little-studied flood basalt formations of the Jurassic ~180 Ma Karoo large igneous province. The expedition was related to the recently launched MARZ (Magmatism in the Africa- Antarctica Rift Zone) project that is funded by the Academy of Finland. Fieldwork was carried out within three provinces, Tete, Sofala, and Manica in cooperation with Professor Daud Jamal, Dr. Estêvão Sumburane, Mr. Teofilo Gove (all from the Eduardo Mondlane University in Maputo), and Dr. António Alface (Direcção Nacional de Geologia, Tete). During the field campaign, we took lodging in towns and villages and also camped on the forest savannah, and were greatly impressed by the friendliness and helpfulness of the local people. Despite the tropical conditions, the quality of the bedrock outcrops was surprisingly good and we were able to collect ~150 rock samples, well above our initial expectations. The samples will be analysed for major and trace elements, Sr and Nd isotopes, and selected samples will be used for Ar- Ar plagioclase and U-Pb zircon dating. Our samples are from areas that have not been previously studied in detail and the results hopefully will shed light on the mysteries related to the origin of Karoo and other flood basalt provinces. More information about the MARZ project: marzENG.htm
  • Marttila, H.; Tammela, S.; Mustonen, K.-R.; Louhi, P.; Muotka, Timo; Mykrä, Heikki; Klove, B. (IWA Publishing, 2019)
    Hydrology Research 1 June 2019; 50 (3): 878–885
    We conducted a series of tracer test experiments in 12 outdoor semi-natural flumes to assess the effects of variable flow conditions and sand addition on hyporheic zone conditions in gravel beds, mimicking conditions in headwater streams under sediment pressure. Two tracer methods were applied in each experiment: 2–5 tracer-pulse tests were conducted in all flumes and pulses were monitored at three distances downstream of the flume inlet (0 m, 5 m and 10 m, at bed surface), and in pipes installed into the gravel bed at 5 m and 10 m distances. The tracer breakthrough curves (total of 120 tracer injections) were then analysed with a one-dimensional solute transport model (OTIS) and compared with data from the gravel pipes in point-dilution pulse tests. Sand addition had a strong negative effect on horizontal fluxes (qh), whereas the fraction of the median travel time due to transient storage (F200) was determined more by flow conditions. These results suggest that even small additions of sand can modify the hyporheic zone exchange in gravel beds, thus making headwater streams with low sediment transport capacity particularly vulnerable to sediments transported into the stream from catchment land use activities.
  • Heinonen, Aku; Seitsamo-Ryynänen, Minja (2021)
  • Niinikoski-Fusswinkel, Paula; Kotilainen, Mia (2021)
  • Heinonen, Jussi S. (2017)
    Nick Zentner is a senior lecturer at the Department of Geological Sciences of the Central Washington University (CWU), United States. After accidentally ending up with studying geology, he built up interest in its narrative aspects and started working at the CWU in 1992. Initially he was a technician, but he was also responsible for community outreach. He started gaining wider popularity among locals via the University’s own television channel, on which he hosted a geology talk show with other CWU geologists as guests. Today, he has released several highly viewed videos in YouTube, he runs his own geology show on a regional television channel, and guides open-to-all geological excursions in Washington State and its surroundings. The University has acknowledged his contributions in the popularization of geology as a part of his job description. Nick highlights that general interest, rehearsing of public performance, genuineness, and humbleness are the most important characteristics of a science popularizer. An e-mail list that anyone can subscribe to is an important tool in informing his audiences about upcoming public events. Nick’s examples can help those who are interested in popularizing geology in Finland. YouTube would probably be one of the most easily accessible platforms for such projects in the future. It is worth noting, however, that when narrating stories about billion-year-or-more old rocks, the approach should be somewhat different than in the geologically active northwestern United States.
  • Muukkonen, Petteri; Hynynen, Laura; Jäntti, Lauri; Lammi, Panu (2022)
  • Tuomisaari, Johanna Maaria; Junno, Niina; Bäcklund, Pia; Korja, Annakaisa (2022)
  • Järvinen, Matias; Jylhä, Markus; Muukkonen, Petteri (University of Helsinki, Faculty of Science, Department of Geosciences and Geography, 2019)
    Department of Geosciences and Geography C
  • Heinonen, Jussi S. (2013)
    Climbing is not usually associated with Finland, because of lack of mountains, and even the highest hills are generally quite gently sloping. Some impressively steep and tens of meters high rock faces have, however, formed in places that have been strongly affected by shearing, faulting or glacial erosion during the last glacial maximum. Finnish climbing community has been increasingly active since the late 1950’s in developing some of these faces for different climbing styles. Unlike in mountaineering, the main goal in rock climbing is not to conquer the hill, but to climb it via as difficult route as possible. As the bedrock of Finland is characterized by Precambrian granites and gneisses, most of the climbing takes place along crack lines or thin edges and crystal faces, which means that the routes are often rather demanding. At current, about 100 rope climbing and over 400 bouldering destinations can be found in Finland. Climbers have traditionally respected nature and Finnish climbers and landowners have built relatively good relationships over the years.
  • Yli-Halla, Markku Juhani; Suomela, Raija (2019)
  • Veikkolainen, Toni; Oinonen, Kati; Vuorinen, Tommi; Kortström, Jari; Mäntyniemi, Päivi; Lindblom, Pasi; Uski, Marja; Tiira, Timo (Institute of Seismology, University of Helsinki, 2021)
    In 2019–2020, the Institute of Seismology set up, in collaboration with the City of Helsinki, a seismic network, HelsinkiNet, consisting of three stations. The stations of the network were in operation in Kuninkaantammi (KUNI), Lauttasaari (LAUT), and Vuosaari (VUOS) in association with the automatic observation systems of Finland and the Helsinki region. The noise level of stations was low considering their locations, and no long interruptions to data delivery have taken place. In addition to HelsinkiNet, stations HEL1-HEL5 established for the monitoring of the St1 deep heat project were operational in the western part of Helsinki region. In 2020, the number of confirmed seismic events within 30 km from the Central Railway Station of Helsinki was 484, most of them explosions. Induced earthquakes happened in Espoo, particularly in Otaniemi, but also in Koskelo. Three natural earthquakes occurred, two of them were 0.7-magnitude events in Vantaa and one was a –0.5-magnitude event in Laajaranta. The number of natural and induced earthquakes of at least magnitude 0.0 was 24. Most of the macroseismic observations of earthquakes were associated with the St1 geothermal plant project in Otaniemi, Espoo.
  • Veikkolainen, Toni; Oinonen, Kati; Vuorinen, Tommi; Kortström, Jari; Mäntyniemi, Päivi; Lindblom, Pasi; Luhta, Tuija; Hällsten, Jennifer Mikaela Alexandra; Tiira, T. (Institute of Seismology, University of Helsinki, 2022)
    2021 was the first fully operational year of the HelsinkiNet, a collaborative seismological observation network of the Institute of Seismology and City of Helsinki. The stations KUNI, LAUT, and VUOS continued in association with the national and regional automatic detection systems. In May 2021, operation of the station RSUO began for monitoring the geothermal heat plant of Ruskeasuo. In addition, stations HEL1-HEL5 were in operation in Helsinki and Espoo, although HEL4 stopped operating in April 2021. A total of 3483 confirmed seismic events occurred within 30 km of the Central Railway Square of Helsinki. Only one of them was a natural earthquake. It occurred in the sea area of Kirkkonummi on the 28th of August 2021. A single induced earthquake was observed in southeastern Espoo on the 2nd of March 2021, and again on the 4th of July 2021. A swarm of probably induced earthquakes occurred in the same area on the 27th and 29th of December 2021. The vast majority of observed seismic events were explosions. Particular attention was paid to a detonation in the low atmosphere in northern Pasila on the 11th of September 2021. The location and the probable reason for the event were resolved in cooperation between the Institute of Seismology and the Ursa Astronomical Association.
  • Helmisaari, Heljä-Sisko Marketta; Kaarakka, Lilli M; Korpela, Leila; Lindroos, Antti-Jussi; Nieminen, Tiina M; Nöjd, Pekka; Smolander, Aino (Suomen Maaperätieteiden seura, Helsingin yliopisto, Maataloustieteiden Osasto, 2019)
    Pro Terra