Middle Jurassic multi‐scale transgressive–regressive cycles: An example from the Lusitanian Basin. (22nd February 2023)

• Record Type: Journal Article
• Authors: Magalhães, Antonio J. C.; Terra, Gerson J. S.; Guadagnin, Felipe; Fragoso, Daniel G. C.; Menegazzo, Mirian C.; Pimentel, Nuno L. A.; Kumaira, Sissa; Fauth, Gerson; Santos, Alessandra; Watkins, David K.; Bruno, Mauro D. R.; Ceolin, Daiane; Baecker‐Fauth, Simone; Gabaglia, Guilherme P. R.; Teixeira, Washington L. E.; Lima‐Filho, Francisco P.
• Is Part Of: Depositional record. Volume 9:Number 1(2023)
• Page Start: 174
• Page End: 202
• Publication Date: 2023-02-22
• Subjects: Bathonian–early Callovian age -- Central Lusitanian Basin -- high‐frequency sequences -- multi‐scale T–R cycles; Sediments (Geology) -- Periodicals; Sedimentology -- Periodicals; Sedimentation and deposition -- Periodicals; 552.5
• DOI: 10.1002/dep2.223
• Languages: English
• ISSNs: 2055-4877

Abstract

Abstract: Multi‐scale transgressive–regressive cycles from the mid‐Jurassic were recognised in the Central Lusitanian Basin, Portugal. These cycles allow the depositional evolution of the basin to be better understood and aid in the construction of stratigraphic sequences composed of three hierarchies. The stacking pattern of high‐frequency transgressive–regressive sequences forms larger clusters that define medium‐frequency transgressive–regressive sequences. Likewise, the stacking pattern of medium‐frequency transgressive–regressive sequences generates two Bathonian–early Callovian low‐frequency transgressive–regressive sequences. Integration of several methods supported the interpretation of facies associations representing clastic deposition in offshore to shoreface environments and carbonate sediments in outer to inner ramp settings. New data from calcareous nannofossils and dinoflagellate assemblages constrained the interval's Bathonian–early Callovian age, thus unveiling the Middle–Upper Jurassic disconformity and filling the Middle Jurassic stratigraphic record gap in the Central Lusitanian Basin. This study may be helpful for similar successions in Tethyan domains and comparable depositional settings elsewhere. Abstract : Middle Jurassic multi‐scale transgressive–regressive cycles were recognised in the Central Lusitanian Basin, Portugal. New data from calcareous nannofossils and dinoflagellate assemblages constrained the Bathonian–early Callovian age for the studied interval, thus filling the gap of the Middle Jurassic in the Central Lusitanian Basin. Using descriptive criteria to identify sequences based on the T–R cycle anatomy, recurrence, and trends, cyclic stratigraphy has enabled the definition of a conceptual model for the deposition of the studied section that is more robust than conventional interpretations.