Sökning: "late Pliensbachian"

Hittade 3 uppsatser innehållade orden late Pliensbachian.

  1. 1. Stratigraphy and palaeoenvironment of the early Jurassic volcaniclastic strata at Djupadalsmölla, central Skåne, Sweden

    Master-uppsats, Lunds universitet/Geologiska institutionen

    Författare :Per Wahlquist; [2023]
    Nyckelord :volcaniclastic; Djupadalsmölla; CSVP; palynomorphs; early Jurassic; late Pliensbachian; Earth and Environmental Sciences;

    Sammanfattning : From the almost 200 volcanic outcrops in the Central Skåne Volcanic Province (CSVP), only three are of volcaniclastic material. These volcanoclastics, and the transition to the underlying crystalline basement, have been investigated for the first time in a drill core (KBH2) from Djupadalsmölla in order to understand the stra-tigraphy, depositional process, age of deposition, and depositional environment. LÄS MER

  3. 2. The Jurassic extinction events and its relation to CO2 levels in the atmosphere : a case study on Early Jurassic fossil leaves

    Kandidat-uppsats, Lunds universitet/Geologiska institutionen

    Författare :Liina Santasalo; [2013]
    Nyckelord :conifers; Pliensbachian; Australian; Early Jurassic; stomatal proxy; palaeo-CO2; koldioxidhalt; klimat; Australien; tidig Jura; Marburg subgroup; Allocladus helgei; stomata index; CO2; Earth and Environmental Sciences;

    Sammanfattning : The Mesozoic was a so-called “hothouse” time period in Earth’s history, with high concentrations of atmospheric CO2 and elevated temperatures, but the exact climate evolution is not fully known for the entire inter-val. The Early Jurassic for instance is believed to have been a warm period, flanked by two episodes of extremely high CO2, coinciding with environmental degradation and mass extinctions: the Triassic-Jurassic (200 Ma) and the early Toarcian (183 Ma) mass extinction events. LÄS MER

  4. 3. Palynostratigraphy and palaeoclimatic analysis of Lower-Middle Jurassic (Pliensbachian - Bathonian) of the Inner Hebrides, NW Scotland

    Magister-uppsats, Lunds universitet/Geologiska institutionen

    Författare :Sissa Stefanowicz; [2008]
    Nyckelord :palynologi; jura; miospor; paleoklimat; Inre Hebriderna; Skottland; palynology; Jurassic; miospore; palaeoclimate; Inner Hebrides; Scotland; Earth and Environmental Sciences;

    Sammanfattning : A palynostratigraphic investigation of partly ammonite dated, Pliensbachian to Bathonian (Early – Middle Jurassic) strata on the Isles of Skye and Raasay, Inner Hebrides in Northwest Scotland, has recovered a diverse but not always well preserved miospore flora and a less diverse dinoflagellate cysts flora. The studied interval has been subdivided into five biozones, A - E, based on the first occurrence, common occurrence, first common occurrence, and relative abundance of pollen and spore key taxa. LÄS MER