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  • Salminen, Johanna (Helsingin yliopisto, 2009)
    The importance of supercontinents in our understanding of the geological evolution of the planet Earth has been recently emphasized. The role of paleomagnetism in reconstructing lithospheric blocks in their ancient paleopositions is vital. Paleomagnetism is the only quantitative tool for providing ancient latitudes and azimuthal orientations of continents. It also yields information of content of the geomagnetic field in the past. In order to obtain a continuous record on the positions of continents, dated intrusive rocks are required in temporal progression. This is not always possible due to pulse-like occurrences of dykes. In this work we demonstrate that studies of meteorite impact-related rocks may fill some gaps in the paleomagnetic record. This dissertation is based on paleomagnetic and rock magnetic data obtained from samples of the Jänisjärvi impact structure (Russian Karelia, most recent 40Ar-39Ar age of 682 Ma), the Salla diabase dyke (North Finland, U-Pb 1122 Ma), the Valaam monzodioritic sill (Russian Karelia, U-Pb 1458 Ma), and the Vredefort impact structure (South Africa, 2023 Ma). The paleomagnetic study of Jänisjärvi samples was made in order to obtain a pole for Baltica, which lacks paleomagnetic data from 750 to ca. 600 Ma. The position of Baltica at ca. 700 Ma is relevant in order to verify whether the supercontinent Rodinia was already fragmented. The paleomagnetic study of the Salla dyke was conducted to examine the position of Baltica at the onset of supercontinent Rodinia's formation. The virtual geomagnetic pole (VGP) from Salla dyke provides hints that the Mesoproterozoic Baltica - Laurentia unity in the Hudsonland (Columbia, Nuna) supercontinent assembly may have lasted until 1.12 Ga. Moreover, the new VGP of Salla dyke provides new constraint on the timing of the rotation of Baltica relative to Laurentia (e.g. Gower et al., 1990). A paleomagnetic study of the Valaam sill was carried out in order to shed light into the question of existence of Baltica-Laurentia unity in the supercontinent Hudsonland. Combined with results from dyke complex of the Lake Ladoga region (Schehrbakova et al., 2008) a new robust paleomagnetic pole for Baltica is obtained. This pole places Baltica on a latitude of 10°. This low latitude location is supported also by Mesoproterozoic 1.5 1.3 Ga red-bed sedimentation (for example the Satakunta sandstone). The Vredefort impactite samples provide a well dated (2.02 Ga) pole for the Kaapvaal Craton. Rock magnetic data reveal unusually high Koenigsberger ratios (Q values) in all studied lithologies of the Vredefort dome. The high Q values are now first time also seen in samples from the Johannesburg Dome (ca. 120 km away) where there is no impact evidence. Thus, a direct causative link of high Q values to the Vredefort impact event can be ruled out.
  • Liikanen, Ilkka; Sallamaa, Kari (Kirjallisuuden laitos. Julkaisuja 4, Oulun yliopisto. Oulu 1982, 1982)
  • Susanna Wolkoff (Helsingin yliopisto, 2006)
  • Susanna Wolkoff (Helsingin yliopisto, 2009)
  • Seppänen, Laura; Schaupp, Marika; Toiviainen, Hanna; Ala-Laurinaho, Arja; Heikkilä, Heli; Kira, Mari; Korpelainen, Eija; Lallimo, Jiri; Ruotsala, Riikka; Uusitalo, Hanna (Toiminnan, kehityksen ja oppimisen tutkimusyksikkö CRADLE, Helsingin yliopisto, 2012)
  • Alam, Yunis; Husband, Charles (Helsinki Collegium for Advanced Studies, 2012)
  • Aldrin, Viktor (Helsinki Collegium for Advanced Studies, 2015)
    This article focuses on expressions of bereavement and religious coping in medieval miracle stories from Sweden. The stories come from the collections of St. Birgitta (Bridget) of Sweden, the Blessed Bishop Nicolaus Hermanni (Sw. Nils Hermansson) of Linköping and the Blessed Katarina of Vadstena, and were recorded in the fourteenth and fifteenth centuries. Catherine M. Sanders’s modern five stages of bereavement have been used as the theory of analysis through Kay Talbot’s adaptation of the theory for parents in grief. This theoretical foundation has provided new insights into how parental grief was expressed in medieval Sweden – and in stark contrast to Continental research on the same topic. Parents of both sexes expressed their grief outwardly through tears and crying, and a reluctance to accept that their children were dead. Throughout the miracle stories, lay people constructed their own prayers for miraculous intervention without the aid of any priests. This makes fathers and mothers in medieval Sweden agents of their own in terms of praying to God and being able to construct their own forms of religious coping.
  • Grossman, Volker; Poutvaara, Panu (Helsinki Center of Economic Research, 2006)
  • Tukiainen, Janne (Helsinki Center of Economic Research, 2008)
  • Pellinen, Sini; Minoia, Paola (Department of Geosciences And Geography, University of Helsinki, 2013)
  • Unknown author (Helsinki Collegium for Advanced Studies, 2015)
  • Wahlgren, Staffan (Helsinki Collegium for Advanced Studies, 2015)
    In this article I will discuss the presentation of the past and, to some extent, the present (or immediate past) in selected Byzantine chronicles of the ninth and tenth centuries, from prosopographical-political, geographical and other perspectives. Particular emphasis will be placed on the Chronicle of Theophanes the Confessor and the Chronicle of Symeon the Logothete. My main contention will be that changes in a narrative’s form can, to a considerable degree, explain why the knowledge therein is so different in each text. In other words, how a text is organised decides the kind of information it will contain, and therefore, the value of a text as an historical document is very much dependent upon its form.
  • Kultti, Klaus; Takalo, Tuomas; Toikka, Juuso (Helsinki Center of Economic Research, 2007)
  • Palokangas, Tapio (Helsinki Center of Economic Research, 2008)
  • Tåg, Joacim (Helsinki Center of Economic Research, 2007)
  • Haaparanta, Pertti; Kuisma, Kirsti (Helsinki Center of Economic Research, 2006)
  • Lankoski, J.; Lichtenberg, E.; Ollikainen, M. (Helsingin yliopisto, taloustieteen laitos, 2004)
  • Honkapohja, Seppo; Mitra, Kaushik (University of Helsinki, 2003)
  • Honkapohja, Seppo; Mitra, Kaushik (University of Helsinki, 2003)