Bioestratigrafía y sedimentología de los sedimentos detríticos del sector Macandamine Secuencia 2

Abstract

Abstract: This research studies the biostratigraphy and sedimentology of a sequence from the Macandamine sector (Paltas Canton) with the aim of establishing chronostratigraphic sequences and stratigraphic biozones. Through the analysis of the fossil record and its sedimentary characteristics, it was determined that the macrofossils are well preserved and have a good to acceptable taphonomic index, suggesting low-energy environmental conditions during sedimentation. This is directly related to the transport index, which was determined to be low. The study of planktonic foraminifera allowed for the establishment of temporal distribution ranges, highlighting the presence of the species Dicarinella primitiva as a key fossil, representing the age range of this sequence between 86.3 and 89.8 million years ago, corresponding to the Coniacian. This study contributes to a better understanding of the area's paleoenvironment, suggesting that the sequence represents a mid-shelf marine environment notable for the presence of benthic foraminifera of the genera Praebulimina and Allomorphina, as well as low-energy conditions conducive to the accumulation and preservation of macro- and microfossils.