Sökning: "Silurian"

Visar resultat 1 - 5 av 39 avhandlingar innehållade ordet Silurian.

1. 1. Silurian vertebrates of Gotland (Sweden) and the Baltic Basin

   Författare :Oskar Bremer; Henning Blom; Per E. Ahlberg; Tiiu Märss; Héctor Botella; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; early vertebrates; vertebrate microremains; scale taxonomy; early vertebrate distribution; environmental preferences; Silurian; Baltic Basin; Gotland; Sweden; Biology with specialization in Evolutionary Organismal Biology; Biologi med inriktning mot evolutionär organismbiologi;

   Sammanfattning : During the Silurian, the Swedish island Gotland was positioned close to the equator and covered by a shallow sea called the Baltic Basin. The sedimentary rocks (predominantly carbonates) comprising most of the island today were initially formed in this warm sea, and the relatively complete succession of rocks often contains fossil fragments and scales from early vertebrates, including heterostracans, anaspids, thelodonts, osteostracans, acanthodians, and a stem-osteichthyan. LÄS MER

3. 2. Diversity and Life Habits of Silurian Strophomenide Brachiopods of Gotland

   Författare :Ole Andreas Hoel; Lars E. Holmer; Michael Bassett; David A. T. Harper; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Gotland; Silurian; brachiopod; functional morphology; ecology; Llandovery; Wenlock; Ludlow; Strophomenoidea; Geovetenskap; Earth sciences; Geovetenskap;

   Sammanfattning : The Superfamily Strophomenoidea is a very diverse group of brachiopods in the Early Palaeozoic. In the Silurian succession on Gotland, they are among the most easily identifiable, and commonly found fossils. LÄS MER

4. 3. Late Ordovician-Early Silurian facies development and stratigraphy of Jämtland, central Sweden

   Författare :Peter Dahlqvist; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biostratigraphy; Sedimentology; Stratigrafi; Stratigraphy; Paleontologi; Palaeontology; Jämtland; provenance; brachiopods; conodonts; Hirnantian; Silurian; Ordovician; glaciation; eustasy; Sedimentologi; sedimentology;

   Sammanfattning : This thesis is based on studies of Lower Palaeozoic sedimentary successions within the central Scandinavian Caledonides. These deposits have been transported by considerable nappe displacement (several kilometres), and are today relatively isolated from the nearest coeval outcrops (Dalarna 250 km, Oslo Region 350 km). LÄS MER

5. 4. Silurian Carbonate Platforms of Gotland, Sweden - Archives of Local, Regional and Global Environmental Changes

   Författare :Mårten Eriksson; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sedimentologi; Sedimentology; fysisk geografi; Geologi; physical geography; Geology; Gotland; Silurian; Facies; Carbonate platforms; Sequence stratigraphy; Stable isotopes; Palaeoclimate;

   Sammanfattning : This thesis treats the Silurian carbonate platforms of Gotland, Sweden, which formed close to the equator within the East Baltic Basin. Three different time intervals, all involving changes in facies composition and structure of the platforms, have been studied; Late Homerian, latest Homerian ? earliest Gorstian, and late Ludfordian, respectively. LÄS MER

7. 5. Early Palaeozoic jawed polychaetes with focus on polychaetaspids and ramphoprionids from the Silurian of Gotland, Sweden

   Författare :Mats Eriksson; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fysisk geografi; Geologi; physical geography; Geology; chemistry; palaeobiogeography; palaeoecology; taxonomy; apparatus reconstructions; Silurian; Recent; Ordovician; early Palaeozoic; scolecodonts; Annelida; polychaeta;

   Sammanfattning : Jawed polychaete annelid worms were abundant and diverse in the early Palaeozoic seas and their jaws (scolecodonts) are common microfossils in sedimentary rocks of that age. Despite their abundance, relatively little work has been focused on these fossils. LÄS MER