Tagasi otsingusse
Põldsaar et al., 2019

A siliciclastic shallow-marine turbidite on the carbonate shelf of the Ordovician Baltoscandian palaeobasin

Põldsaar, K., Ainsaar, L., Nemliher, R., Tinn, O., Stinkulis, G.
DOI10.3176/earth.2019.01
Aasta2019
AjakiriEstonian Journal of Earth Sciences
Köide68
Number1
Leheküljed1-14
Tüüpartikkel ajakirjas
OpenAccess
LitsentsCC BY 4.0
Eesti autor
Keelinglise
Id9552

Abstrakt

A metre-scale thick siltstone–sandstone lobe is described within the Dapingian outer ramp argillaceous limestone facies of the Baltoscandian palaeobasin. This bed is referred to as the Volkhov Oil Collector in previous studies due to its hydrocarbon accumulation potential. It formed on the palaeoslope of the regional Jelgava Depression, which represents an elongated axial region of the deepest part of the Ordovician Baltoscandian sedimentary basin. Sedimentological and petrological analysis of this siliciclastic bed in core sections shows that it was deposited as a result of a single event of turbidite flow. The internal structure of the turbidite bed follows the classical Bouma divisions of the turbidite sequence model. The triggers of this single siliciclastic turbidite bed within a tectonically inactive shallow carbonate basin are analysed. It is concluded that a rare tsunami might have eroded and transported sediments in suspension from land to shallow sea. Suspension fallout would have evolved into a density flow and later into a turbidity current that travelled into the deeper parts of the basin, depositing siliciclastic material at the slope of the Jelgava Depression. The occurrence of the Volkhov Oil Collector turbidite bed on the tectonically relatively stable and flat-bottomed Baltoscandian palaeobasin suggests that turbidite events can take place in rare cases also in epicontinental environments.

Viimati muudetud: 11/14/2020
KIKNATARCSARVTÜ Loodusmuuseumi geokogudEesti Loodusmuuseumi geoloogia osakond
Leheküljel leiduvad materjalid on enamasti kasutamiseks CC BY-SA litsensi alusel, kui pole teisiti määratud.
Portaal on osaks teadustaristust ning infosüsteemist SARV, majutab TalTech.
Open Book ikooni autor Icons8.