- Tytuł:
- The mineralogical record of the Early Toarcian stepwise climate changes and other environmental variations (Ciechocinek Formation, Polish Basin)
- Autorzy:
- Brański, P.
- Powiązania:
- https://bibliotekanauki.pl/articles/2061010.pdf
- Data publikacji:
- 2012
- Wydawca:
- Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
- Tematy:
-
clay minerals
bulk rock data
warming event
palaeoclimate
Ciechocinek Formation
Early Toarcian
Polish Basin
minerały ilaste
okres ocieplenia
Formacja Ciechocińska
wczesny toark
basen polski - Opis:
- After the cooling episode of the Late Pliensbachian, a major oceanic anoxic event occurred during the prominent warming event of the Early Toarcian (183 Myr; Early Jurassic). In this paper, new mineralogical and geochemical data (XRD, XRF, SEM, and TOC) measured on four cores from the Polish Basin are presented in order to document the regional impacts of these disturbances at a high sampling resolution. The results show that the clay mineral assemblages (<2 μm fraction) and vertical variations in kaolinite content are generally similar basin-wide and were controlled by the intensity of chemical weathering and climate changes. However, sea-level changes and variations in terrigenous supply are reflected in the bulk rock data. The spatial variability in clay mineral proportions may also be influenced by the distance from shoreline and the lithology of source areas. Generally, the clay minerals from the Polish Basin confirm the stepped nature of the Early Toarcian warming event. After a predominance of illite in the lower part of the Ciechocinek Fm., which suggests a temperate climate in the early tenuicostatum Zone, rises in kaolinite in the middle part of the Ciechocinek Fm. indicate a stronger weathering rate and high rainfall due to the onset of the warming event in the late tenuicostatum Zone. Importantly, the initial phase of climate change recorded by clay minerals seems to slightly precede the first step of the negative carbon isotope excursion ascribed to massive greenhouse gas releases.
- Źródło:
-
Volumina Jurassica; 2012, 10, 1; 1--24
1896-7876
1731-3708 - Pojawia się w:
- Volumina Jurassica
- Dostawca treści:
- Biblioteka Nauki
Artykuł