Discussion Comment on “Apatite fission track and (U–Th)/He data from Fennoscandia: An example of underestimation of fission track annealing in apatite” by Hendriks and Redfield [Earth Planet. Sci. Lett. 236 (443–458)] Sven Åke Larson a , Charlotte E. Cederbom b, ⁎ , Eva-Lena Tullborg a , Jan-Petter Stiberg c a Department of Geology, Earth Sciences Centre, Göteborg University, Box 460, S-405 30 Göteborg, Sweden b GeoForschungsZentrum Potsdam, Albert-Einstein-Strasse, Telegrafenberg, 14473 Potsdam, Germany c Ammerudgrenda 271, 0960 Oslo, Norway Received 12 December 2005; received in revised form 9 March 2006; accepted 7 June 2006 Available online 20 July 2006 Editor: K. Farley Abstract In a recent paper Hendriks and Redfield question the existence of major episodes of burial and subsequent denudation in old cratonic settings. They use Fennoscandia as an example, a continental shield region once covered by foreland basin deposits related to the Caledonian orogen, but today characterized by an exposed Precambrian basement. Hendriks and Redfield argue against a significant Caledonian foreland basin cover, referring to a selection of the numerous thermal indicator studies that have been performed in the region. Furthermore, they discern an inconsistency between previously published fission track and (U–Th)/He results in the region, and suggest an alternative interpretation of the apatite fission-track data from Fennoscandia. Here we present geological arguments and highlight the numerous studies, only briefly mentioned or not referred to at all by Hendriks and Redfield, that strongly support the former existence of thick and extensive deposits on the Caledonian foreland. Furthermore, we discuss the alleged inconsistency between the different data sets by examining the data referred to more closely. Finally, we evaluate the significance of the suggested inverse correlation between fission track age and 238 U concentration presented by Hendriks and Redfield. There is, in fact, no published example of an inconsistency between the two methods concerning Paleozoic cooling in Fennoscandia at present, and the inverse relationship stated by the authors is poorly constrained. Therefore, although radiation- enhanced lattice recovery may have an influence on the apatite fission-track age and should be examined further we conclude that the study by Hendriks and Redfield is poorly constrained, their argumentation weakly and sometimes wrongly founded, and that the thermochronology data from Fennoscandia indeed do reflect sedimentary loading. © 2006 Elsevier B.V. All rights reserved. Keywords: FT dating; (U–Th)/He dating; thermochronology; Fennoscandia; foreland basin; Palaeozoic 1. Introduction Hendriks and Redfield [1] discuss the inconsistency which sometimes occurs between (U–Th)/He and fission track (FT) measurements of apatite from old, cratonic Earth and Planetary Science Letters 248 (2006) 561 – 568 www.elsevier.com/locate/epsl ⁎ Corresponding author. E-mail addresses: sal@geo.gu.se (S.Å. Larson), cederbom@gfz-potsdam.de (C.E. Cederbom), evalena@swipnet.se (E.-L. Tullborg), fission@online.no (J.-P. Stiberg). 0012-821X/$ - see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.epsl.2006.06.018