Growth-related 1.85-1.55 Ga magmatism in the Baltic Shield; a review addressing the tectonic characteristics of Svecofennian, TIB 1-related, and Gothian events - A reply

Transitioning from Svecofennian to Transcandinavian Igneous Belt (TIB) magmatism in SE Sweden: Implications from the 1.82 Ga Eksjö tonalite

“…This challenging configuration is not always apparent due to a conflicting TIB terminology that obscures the tectonic relationships between the OJB and TIB magmatism (see discussion in Wikström 2001 andLarson 2001). In any case, the results of this study confirm that the 1.83-1.82 Ga OJB magmatism separates the TIB 1 magmatism (1.81-1.77 Ga, Larson & Berglund 1992;Åhäll & Larson 2000) from the ~1.85 Ga magmatism that resulted in several TIB-like intrusions along the Svecofennian margin, exemplified by the U-Pb dated Askersund and Hälla granites (Wikström 1996;Wikström & Persson 2002) and granites in the Revsund area (Högdahl 2000).…”

“…Truncation of Svecofennian structures by such calc-alkaline ~1.85 Ga intrusions (e.g. Samfallet tonalite, Wikström 1996; Nygården norite, Claeson & Andersson 2000) collectively imply northeastward subduction below Svecofennian crust in an Andean-type setting by 1.85 Ga (Åhäll & Larson 2000(Åhäll & Larson , 2001.…”

“…This alternative may be constructive, but only if the 1.83-1.82 Ga OJB granitoids are shown not to represent a suspect terrane. A third option could be to reassess the Svecofennian to include the growth-related, ~1.85 Ga events along SW Baltica, represented by the Askersund suite (Åhäll & Larson 2000(Åhäll & Larson , 2001 and references therein) and the broadly coeval granitoid rocks in the Revsund area further north (Högdahl 2000). This option merits special attention if the GFF 124 (2002) Åhäll et al: Transitioning from Svecofennian to Transcandinavian Igneous Belt magmatism in SE Sweden 223 Ljusdal granitoid (1843±2 Ma, Delin 1993) is shown to represent such a young event of calc-alkaline magmatism well within what has long been known as the Svecofennian Domain.…”

Character and origin of variably deformed granitoids in central southern Sweden: implications from geochemistry and Nd isotopes

“…Johansson et al , ; Mansfeld, ). The TIB may also be subdivided based on magmatic ages, but the different groupings are somewhat controversial (Åhäll and Larson, , ; Andersson and Wikström, , ). The groups used in this paper are: TIB‐0 at 1.85–1.83 Ga (Ahl et al , ), TIB‐1 at 1.81–1.76 Ga (Larson and Berglund, ) and TIB‐2 at 1.71–1.65 Ga (Andersson and Wikström, ; Brander et al , ).…”