Major tectonic rotation along an oceanic transform zone, northern Iceland: Evidence from field and paleomagnetic investigations

Statistical Analysis of Small Faults in Rotated Blocks of Crust Near the Húsavík‐Flatey Transform Fault, Northern Iceland

“…Our regressions against fault-normal distance ignore fault-parallel variability in the extent of rotation. Likewise, Young et al (1985), Titus et al (2018), andYoung et al (2020) do not discuss variability along fault strike. However, Horst et al (2018) interpret the variability in their paleomagnetic data as evidence for rotation of irregular crustal blocks (Figure 2d) with potential variation along the strike of the Húsavík-Flatey fault.…”

“…Previous studies have suggested various processes to explain this rotation, including intermittent coupling along the transform fault (Horst et al, 2018;Stefansson et al, 2008), and broadly distributed transcurrent deformation prior to the development of a major fault (Young et al, 1985(Young et al, , 2020. Workers have speculated about the complications that rotation on Flateyjarskagi presents for paleostress analysis (Bergerat et al, 2000;Horst et al, 2018;Young et al, 1985Young et al, , 2020. However, studies focused on outcrop-scale fault data with slickenside straie (Angelier et al, 2000;Bergerat et al, 2000;Garcia & Dhont, 2005;Garcia et al, 2002) have primarily interpreted the unusually complex distribution of fault orientations near the Húsavík-Flatey fault in terms of stress variability, rather than considering the effects of block rotation.…”

“…The extent of clockwise rotation increases progressively approaching the fault, likely exceeding 100° in the nearest on-land areas (Horst et al, 2018;Titus et al, 2018;Young et al, 2020). Previous studies have suggested various processes to explain this rotation, including intermittent coupling along the transform fault (Horst et al, 2018;Stefansson et al, 2008), and broadly distributed transcurrent deformation prior to the development of a major fault (Young et al, 1985(Young et al, , 2020. Workers have speculated about the complications that rotation on Flateyjarskagi presents for paleostress analysis (Bergerat et al, 2000;Horst et al, 2018;Young et al, 1985Young et al, , 2020.…”

The Iceland Palaeomagnetism Database (ICEPMAG)

“…Palaeomagnetic techniques have also been used to understand the tectonic history of the island (Jancin 2010;Horst et al 2018;Titus et al 2018;Young et al 2018), e.g. palaeomagnetic directions combined with structural data have been used to quantify varying clockwise rotation with distance from the Husavík-Flatey fault in northern Iceland (Titus et al 2018).…”

“…It would not be advised to include data collected to understand, e.g. the influence of tectonic rotation in northern Iceland (Jancin 2010;Horst et al 2018;Titus et al 2018;Young et al 2018) in statistical analyses of palaeosecular variation. This is a compromise in the construction of the ICEPMAG database.…”