ELSEVIER Sedimentary Geology 113 (1997) 149-159 Sedimentary Geology Provenance and tectonic implications of heavy minerals in Pliocene-Pleistocene siliciclastic sediments of the southern Apennines, Italy P. Acquafredda ay*, A. Fornelli a, G. Piccarreta a,b, V. Summa b a Dipartimento Geomineralogico, via E. Orabona 4, 70125 Bari, Italy b Istituto di Ricerca sulle Argille, Tito Scala Potenza, Italy Received 1 July 1996; accepted 27 March 1997 Abstract During the late Tortonian-Pleistocene, rifting in the Tyrrhenian region and compression in the Apennines coexisted, with an eastward migration of the rift basin-thrust belt-foredeep systems. In a northwest-southeast area of the southern Apennine Pliocene deposits, accumulated in piggy-back basins, and Pliocene-Pleistocene sediments deposited in the foredeep basins, are contiguous. Here our attention is focused on the heavy minerals, which are sensitive indicators of source rocks. Garnet, blue amphibole, staurolite, clinopyroxene, epidote have been analysed and compared with the minerals of the likely protoliths. Blue amphibole and staurolite derive from Early Miocene ‘Tufiti di Tusa e Arenarie di Corleto’ Formation; pyroxenes derive from Pleistocene Vulture volcanics and, possibly from Pliocene volcaniclastic strata cropping out in Basilicata. Interestingly, blue amphibole and staurolite, present in the Early Miocene volcanolithic and quartzofeldspathic sandstones of the ‘Tufiti di Tusa e Arenarie di Corleto’ Formation, are absent in Tortonian siliciclastic strata, but appear again in Pliocene-Pleistocene siliciclastic sediments. The space-time distribution of these minerals was controlled by important motphostructural modifications affecting the southern Apennine thrust belt. Keywords: sedimentary petrology; clay; sand; mineral chemistry; tectonics 1. Introduction Provenance models of sedimentary rocks have, generally taken into account the mineralogical and/or chemical composition of sandstones and shales (e.g. Dickinson, 1970; Dickinson and Suczek, 1979; Van de Kamp and Leake, 1995). The compositions of the heavy minerals, as well as the mineral assem- *Corresponding author. Tel.: +39 80 5442-613; Fax: f39 80 5442-591. E-mail: acquafredda@lgxserver.uniba.it blage of fine- and coarse-grained rock fragments, are sensitive indicators of source rocks (e.g. Morton, 1985; Nechaev and Isphording, 1993; Fornelli and Piccarreta, 1997). This paper deals with the types and chemi- cal compositions of heavy minerals occurring in Pliocene-Pleistocene sedimentary strata deposited in piggy-back and foredeep basins connected with east- ward migration of the southern Apennine chain. The chemical data were compared with those from the same minerals occurring in the likely source rocks. 0037-0738/97/$17.00 0 1997 Elsevier Science B.V. All rights reserved. PZZ SOO37-0738(97)00051-l