Paleomagnetic studies of rapakivi complexes in the Fennoscandian shield – Implications to the origin of Proterozoic massif-type anorthosite magmatismShow others and affiliations
2021 (English)In: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 365, article id 106406Article in journal (Refereed) Published
Abstract [en]
Paleomagnetic studies have been performed on five rapakivi related complexes in Sweden and Finland. Poles of varying quality have been defined and the majority of the ∼1640–1497 Ma poles are clustering on low latitudinal positions. By combining data from ∼1500 Ma intrusions a new high-quality pole (Plat: 13°N; Plon: 190°E; A95: 11°, K: 14) for Baltica has been defined. Tectonic reconstructions, on the basis of the new data and previously published high-quality data, indicate that Baltica experienced stable low latitude to equatorial positions during 1640–1470 Ma, temporally coinciding with globally pronounced rapakivi-anorthosite magmatism. Our study argues against single hotspot source for ∼1640–1620 Ma, ∼1590–1520 Ma, and 1470–1410 Ma rapakivi-anorthosites, but supports a model of large-scale superswell under a stationary low-latitude position of supercontinent Nuna for the origin of rapakivi-anorthosite magmatism. However, a possibility for convergent tectonism as the origin cannot be ruled out.
Place, publisher, year, edition, pages
Elsevier, 2021. Vol. 365, article id 106406
National Category
Geophysics
Research subject
Exploration Geophysics
Identifiers
URN: urn:nbn:se:ltu:diva-87300DOI: 10.1016/j.precamres.2021.106406ISI: 000703586700018Scopus ID: 2-s2.0-85118713174OAI: oai:DiVA.org:ltu-87300DiVA, id: diva2:1599250
Funder
Academy of Finland, 319277Swedish Research Council
Note
Validerad;2021;Nivå 2;2021-09-30 (alebob)
2021-09-302021-09-302021-12-13Bibliographically approved