Open AccessThe Turonian-Coniacian deposits of the south-west of the Ulyanovsk-Saratov trough
Author(s) -
Е. М. Первушов,
V. B. Seltser,
Е. А. Калякин,
Е. И. Ильинский,
И. П. Рябов
Publication year - 2019
Publication title -
izvestiâ vysših učebnyh zavedenij. geologiâ i razvedka
Language(s) - English
Resource type - Journals
eISSN - 2618-8708
pISSN - 0016-7762
DOI - 10.32454/0016-7762-2019-5-10-27
Subject(s) - terrigenous sediment , trough (economics) , geology , paleontology , carbonate , benthic zone , biozone , biostratigraphy , sedimentary rock , oceanography , chemistry , organic chemistry , economics , macroeconomics
Integrated study of a series of the Turonian and Coniacian complete geological records has revealed the stratigraphic completeness and specified the faunal contents of the deposits. The south and the southwest of the Ulyanovsk-Saratov trough have been shown to comprise the thickest beds of the studied interval represented by carbonate and carbonate-terrigenous rocks. Northwards, in the zone of the Saratov dislocations, the Turonian – Coniacian bodies are peculiar for terrigenous and terrigenous-carbonate compositions. The beds are ubiquitously monotonous, which complicates identifications at the stage and the substage levels. Distributions of the benthic foraminifer assemblages and the data on the finds of cephalopods, inoceramus, echinoderms, brachiopods and siliceous sponges have allowed to distinguish detailed biostratigraphic units at the level of biozones traced within the examined structural units. An attempt has been made to reconstruct the conditions in the marine environment.