Sourceland controls and dispersal pathways of Holocene muds from boreholes of the Ionian Basin, Calabria, southern Italy

Deep-marine muds were collected from two boreholes (Crati II and Neto VI) along theIonian Calabrian Basin. The samples from the Crati II and the Neto VI boreholes show a similarmineralogical distribution; the marine muds contain mostly phyllosilicates, quartz, calcite, feldsparsand dolomite. Traces of gypsum are present in a few samples. The Neto muds show higher concentrationsof carbonates than the Crati muds; these contents are mainly related to recycling of theNeogene–Quaternary carbonate-rich marine deposits of the Crotone Basin, which mostly influencesthe composition of the Neto muds. The geochemical signatures of the muds mainly reflect a provenancecharacterized by felsic rocks with a minor, but not negligible, mafic supply. In particular, thehinterland composition of the Crati drainage area is on average more mafic in composition than theNeto drainage area. The higher mafic concentration of the Crati sample muds is probably related to theophiolitiferous units that are exposed in the Crati drainage basin. The degree of source area weatheringwas most probably of low–moderate intensity because the Chemical Index of Alteration values for thestudied muds range from 67 to 69. Furthermore, the low and constant Al/K and Rb/K ratios suggestlow–moderate weathering without important fluctuations in weathering intensity. The Al2O3–TiO2–Zrternary diagram and the values of the Index of Compositional Variability indicate that both the Netoand Crati muds are first-cycle, compositionally immature sediments, related to a tectonically active(collision) setting such as the Calabria–Peloritani Arc, where chemical weathering plays a minor role.