English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

A number of discrete slate belts of limited size occur in the Paleoproterozoic volcano-sedimentary Bergslagen Group of western Bergslagen in the Fennoscandian shield of south central Sweden. The Grythyttan Slate Belt, studied for more than a century, forms a single basin with the nearby Saxan Slate Belt. We use the lithostratigraphy of the Grythyttan Slate Formation of the Grythyttan belt, based on basin scale sedimentary facies associations of the volcaniclastic sediments in time and space, as a method to interpret overall tectonic structure. Contrary to traditional views, we reconstruct the GSB as a single overturned limb of a km-scale anticline with horizontal axis in the hanging wall of an east vergent thrust fault, reactivating a listric extensional fault. The fold connects the GSB to the neighboring SSB. Folding and thrusting were related to tectonic closure of a volcanic back- or intra-arc basin. The early folds were subsequently affected by strike-slip shearing and folding around vertical fold axes, which partitioned preferentially into the least competent lithologies (slates and marbles), significantly modifying the map appearance of the slate belt. The late shearing and folding resulted from accretion of Bergslagen onto the Fennoscandian continental margin during the late, Svecobaltic phase of the Svecofennian orogeny. The GSB forms a thin, intraformational wedge in the Bergslagen Group and represents a relatively short interlude with a conglomeratic alluvial fan and turbiditic volcaniclastics followed by more felsic volcanic rocks resembling those of the Bergslagen Group. We suggest that the GSB, and by inference the other slate belts, stem from calderas, as either terrestrial volcanic lakes or shallow submarine eruption centers. The conglomerates are pre-orogenic, not a post-orogenic molasse, as traditionally conceived, and their clast fabric has resulted from sedimentary processes only. Newly determined SIMS U-Pb zircon ages constrain the age of the GSB at ca. 1895 Ma.

The Palaeoproterozoic Grythyttan Field in the Svecofennian Orogen, West Bergslagen, Central Sweden: structure, stratigraphy and age