late Aalenian. The formation is time-equivalent with the Röddinge Formation of the Vomb Trough, the Djupadal Formation in central Skane and the Sorthat Formation of Denmark, with which it shares the Spheripollenites–Leptolepidites and Callialasporites–Perinopollenites Zones. The formation also correlates with the Fjerritslev Formation of the Danish Basin, and the Gassum Formation of the Øresund Basin. The storm-dominated, hummocky cross-stratified Hasle Formation on Bornholm is contemporaneous with the muddy Katslösa Member of the Rya Formation. Basin history Basement The basins where the Rya Formation was deposited form part of the Sorgenfrei-Tornquist Zone (STZ) of the Trans-European Suture Zone, the boundary between Baltica to the northeast and Peri-Gondwana to the southwest. The orogeny was active in the Late Ordovician, or approximately 445 million years ago. At the Carboniferous-Permian boundary around 300 Ma, the area was influenced by the Skagerrak-Centered Large Igneous Province, another large igneous province stretching across the North Sea, the eponymous Skagerrak between Denmark and Sweden and to the northwest up to northern England and Scotland. Break-up of Pangea The basins of southern Sweden and eastern Denmark were formed during the latest Triassic and earliest Jurassic. During this time the Central Atlantic magmatic province (CAMP), with an estimated the largest igneous province in Earth's history, was formed to the present southwest of the Danish-Swedish realm. In the Skåne area, the Central Skåne Volcanic Province was active during the time of deposition of the Rya Formation, commencing around the Sinemurian-Pliensbachian boundary. The earliest magmatism was partly emplaced into and across pre-existing extensional basin structures. The first and the main volcanic phase of this volcanic province occurred in the Early Jurassic (late Sinemurian to Toarcian) at 191–178 Ma. Analysis of the volcanic rocks produced by this Jurassic volcanism suggests a continental Strombolian-type eruptive character close to the oceans of the Early Jurassic. No correlative pyroclastic beds have yet been identified in sedimentary basins surrounding central Skåne. Toarcian During deposition of the Rydebäck Member, the Toarcian turnover happened. This event at the Pliensbachian-Toarcian boundary characterized by widespread anoxic conditions globally, led to the extinction of various groups of flora and fauna. Taxa inhabiting the upper water column were unaffected by anoxia and included ammonites and belemnites. Epifaunal taxa adapted to low-oxygen conditions, such as the buchiids, posidoniids and inoceramids, flourished in the post-extinction environment during the survival interval. Economic geology A study on the geothermal potential of reservoirs in the Øresund Basin published