Catagenic ankerite replacing biogenic calcite in the Marhøgda Bed (Jurassic)

• Main Authors: Sassenfjorden Spitsbergen, Krzysztof P. Krajewski
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Key words; Arctic; Spitsbergen; Jurassic; Marhøgda Bed; ankerite; palaeotemperatures; burial diagenesis; hydrocarbon generation; Svalbard; Adventdalen; Marhøgda
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.488.8964; http://www.polish.polar.pan.pl/ppr23/ppr23-085.pdf

ABSTRACT: The Marhøgda Bed occurring at base of the Adventdalen Group in Sassen− fjorden, Spitsbergen contains common ankerite–replaced belemnite skeletons. Petrographic, major element geochemical, and stable carbon and oxygen isotopic data indicate that the ankerite originated in a catagenic environment associated with thermal degradation of kerogen and hydrocarbon generation in the sequence. It formed at maximum temperature of 150°C under burial of approx. 2 000 m, most probably during Paleogene filling and subsi− dence of the Central Spitsbergen Basin. Dissolution of biogenic calcite and precipitation of ankerite reflect extensive heat flow through the Adventdalen Group sequence related to the Cretaceous and Paleogene magmatic and orogenic activity in Svalbard.