Holocene and Upper Pleistocene stratigraphy of Xochimilco lake, central Mexico

The lacustrine system developed in the basin of Mexico has been great interest studies various geological and social disciplines. Its sediments preserve history environmental changes that occurred during late Quaternary. Between 2016 2018, a set sediment cores were collected Xochimilco sub-basin, located south Mexico. From these sedimentary sequences, master sequence was constructed represents upper 66.5 m deposits. For establishment its stratigraphic column, 15 lithotypes defined from their components which clastic made up silicates dominate, mostly silt clay size. most abundant biogenic fraction is diatoms frequently form oozes, ostracods are common component sequence, locally hashes. Interbedded with volcaniclastic Eight lithological units based on dominant lithotypes. time scale still uncertain for oldest sediments; however, it estimated covers last 300000 to 350000 years. this temporality, oscillations millennial scales inferred. Diatom-rich laminated represent deepest phases lake. deposits higher authigenic calcareous indicate ionic concentration lake shallower. detailed analysis stratigraphy description allows establish an initial interpretation variations depositional environments, provides base paleoclimatic indicators will be supported.