O koncepcji wczesno paleozoicznych wielkich ruchów przesuwczych wzdłuż krawędzi płyty laurentyjskiej i bałtyckiej: replika

Abstract

ON THE CONCEPTION A MAJOR EARLY PALEOZOIC WRENCH MOVEMENT ALONG THE EDGES OF LAURENTIAN AND BALTIC PLATES: REPLY Summary I do not accept the paper by Brochwicz-Lewiński et al. (2) as a satisfactory discussion of my earlier critical remarks (3). My opponents have not dispel all my doubts concerning the weak points of their hypothesis, as for example: 1) their rejection, without discussion, of earlier views on the nature of Early Palaeozoic deformations in the Northern Appalachians and Great Britain, 2) assumption of the pre-Ordovician closure of Northern Iapetus, 3) discrepancies with the Early Palaozoic palaeomganetic reconstructions, 4) coeval operation of subduction and transcurrent fault at the same place,, 5) similarity of origin of their fault zone to the San Andreas fault system. They have not proven, as well, the close pre-Ordovician affinities between such territories as Dobrogea and Scotland which were supposed to lay astride their fault before the inception of movement. Instead of constructive discussion, they have changed their interpretation. Previously they claimed that their large scale wrench movement began in the Early Ordovician „ ... when a mid-oceanic ridge, responsible for sea-floor spreading ... reached the margin of Grampian fold belt ... " and this spreading „ ... was being compensated by „. the above discussed strike-slip fault .„" (1). Now they support and develop an idea - advanced earlier by P.A. Ziegler (5) - of the Late Ordovician oblique collision of the Gondwana derived microplates with Laurentia and Baltica (2). I have not considered this idea because it did not exist in the first version. Although in general I am not against it, its application to the actual case would require a new, perhaps somewhat lengthy discussion, the more so that in a new version I found again some misinterpretations of the earlier works. However, I confess that such a peculiar way of „discussion" is not to my taste and I regard it as not very promising.