The Lapland post-glacial fault province
Organisers: Robert Lagerbäck (SGU, Geological Survey of Sweden, firstname.lastname@example.org), Odleiv Olesen (NGU, Geological Survey of Norway, email@example.com), Christophe Pascal (NGU, Geological Survey of Norway, firstname.lastname@example.org)
Purpose: The present post-congress excursion is the natural follow-up of the proposed symposium: Neotectonics and stress state in formerly glaciated regions by C. Pascal and I. Stewart. The main goal of the excursion is to visit and discuss unique examples on Earth of late- to post-glacial reverse fault scarps located in Lapland (Fig. 1). The late- to post-glacial fault scarps are impressive rock walls extending various tens of kilometers across the landscape and exceeding locally 10 to 20 m high (Figs. 2 and 3). As such they represent dramatic earthquake events having occurred shortly after deglaciation (i.e. ~10ky BP). We will concentrate on "first-class" examples found in Sweden (e.g. the Pärvie, Fig. 3, and Lansjärv faults, Lagerbäck 1979) and in Norway (i.e. the Stuorragura Fault, Olesen 1988, Fig. 2). We propose to show trenched sections across two or three selected faults and discuss fault-associated paleoseismic records (i.e. various types of soft-sediment deformations and landslides, Fig. 4, Lagerbäck 1990). Some additional aspects of the Quaternary geology in the region (e.g. postglacial rebound and palimpsest landscapes) will also be dealt with during the excursion.
Fig. 2: a) Aerial view due to the SE of the post-glacial and reverse Stuoragurra Fault scarp. b) Outline of a trench across
the fault evidencing post-glacial reverse faulting (after Dehls et al. 2000).
|Fig. 3. The Pärvie fault at Lake Kamasjaure in |
northernmost Sweden. The site will be visited
during the excursion.
|Fig. 4. Landslide developed in sandy till at Elmaberget |
north of the Lansjärv fault in northeastern Sweden.
Dating of peat formed inside the scar has given the
slide a minimum age of 8140 ±180 B.P
(uncorrected 14C-age). Hundreds of similar landslide
scars occur in the region.