Mineral composition from sediment core of Lake Alchichica in Mexico

The mineralogical data were measured from a 57-cm-long sediment core retrieved from Lake Alchichica (19° 24' 38 N, 97° 24' 14 W, 2322 masl) at a water depth of ~ 60 m using a Uwitec® coring device equipped with a 9-cm coring tube. Forty freeze-dried ground samples weighing ~0.5 g were sieved through a 150 µm mesh and transferred to a plastic holder using the backside method and scanned from 2 to 70◦ 2θ with a step size of 0.009◦2θ and 0.5 s per step. The analysis was performed using a Bruker® D8-Advance Eco diffractometer (CuKα radiation, λ = 1.5418 Å, 40 kV, 25 mA) coupled with a Lynxeye XE detector (AGEs Laboratory, University of Liège). Mineral identification and quantification were done using the EVA (v4.3) and TOPAS (v5.0) ® Bruker software, respectively. A Rietveld refinement was applied to all the minerals identified by XRD. Unit cell parameters and preferred orientations of the mineral phases were adjusted to obtain a reconstructed XRD pattern as close to the measured pattern.