Provenance of the Novo Oriente Group, southwestern Ceará Central Domain, Borborema Province (NE-Brazil): A dismembered segment of a magma-poor passive margin or a restricted rift-related basin? Carlos E.G. de Araújo a, ⁎, Tercyo R.G. Pinéo a , Renaud Caby c , Felipe G. Costa a , José C. Cavalcante a , Antonio M. Vasconcelos a , Joseneusa B. Rodrigues b a CPRM-Geological Survey of Brazil, R. Antonio Sales 1418, CEP 60135-101, Fortaleza-CE, Brazil b CPRM-Geological Survey of Brazil, Av. SGAN-Quadra 603 — Conjunto J, Parte A,CEP 70830-030, Brasilia-DF, Brazil c Laboratoire de Tectonophysique, Univ. de Montpellier II, Sciences et Techniques, 34095 Montpellier Cedex 05, France abstract article info Article history: Received 11 August 2009 Received in revised form 29 January 2010 Accepted 3 February 2010 Available online 11 February 2010 Keywords: Detrital zircon Sediment geochemistry Provenance Novo Oriente Group Ceará Central Domain Integrated field, LA-MC-ICP-MS geochronology and geochemical data from the Novo Oriente Group have been investigated in order to determine their provenance and possible tectonic setting. This group in the southwestern portion of the Ceará Central Domain, is a well-preserved metavolcanosedimentary sequence, in part exhalative, composed of two distinct formations. The proximal coastal Bonsucesso Formation comprises mainly quartzite and minor basic metavolcanic rocks and is in gradational contact with the distal Caraúbas Formation which constitutes a metapelitic–volcanic-carbonate sequence, including metabasic rocks with pillow structure and sheared serpentinized ultrabasic rocks. The youngest detrital zircon found in the quartzite of the Bonsucesso Formation yielded an age of ca. 2.1 Ga and well-defined peaks around 2.2, 2.3–2.4 and 2.5 Ga. In addition, zircons from a related metabasalt yielded an upper intercept age of 2083 ±28 Ma. We interpret the zircons found in this metabasalt as inherited from the host quartzite. This fact is supported by depleted-mantle Nd model ages (T DM age) from correlated metabasic and metaultrabasic rocks from other places in the Novo Oriente sequence, which have yielded ages between 1.36 and 1.69 Ga, that is younger than the zircon age obtained in the metabasalt extruded over the Bonsucesso quartzite. Geochemical data of the metasedimentary rocks from the Caraúbas Formation indicates a provenance composed of a mixture of felsic and intermediate sources typical of old stable cratons and older continental roots of active tectonic settings. The rocks of the Granja (Médio Coreaú Domain) and Bacajá Complexes (southeastern Amazonian Craton) exposed to the west of the Novo Oriente Group, and largely covered by the Phanerozoic Parnaíba intracratonic basin, are the most likely source rocks. Since the precise age of the Novo Oriente Group is not yet well constrained, two distinct settings may be proposed: (1) it may represent a more evolved basin developed from extensional processes during the Mesoproterozoic (ca. 1.5–1.3 Ga); and (2) it could constitute part of the passive margin systems developed during the break-up of the Rodinia crown copyright supercontinent (ca. 0.95–0.8 Ga), associated with a pre-Brasiliano/Pan-African ocean (e.g. Pharusian Ocean). Crown Copyright © 2010 Published by Elsevier B.V. on behalf of International Association for Gondwana Research. All rights reserved. 1. Introduction Different techniques and studies have been used to determine the source of detritus in clastic material from basins that are found within orogenic systems. It has long been recognized that chemical composition of sedimentary rocks reflects the nature of the source region; and therefore the tectonic setting of the sedimentary basins should be considered as the overall primary control on the composition of sedimentary rocks (Bathia, 1983; Dickinson, 1985; McLennan et al., 1990). The use of geochemical data coupled with detrital zircon U–Pb geochronology has greatly contributed to the understanding of provenance and tectonic setting related to the evolution of sedimentary basins (e.g. Nelson, 2001; Eriksson et al., 2001; Goodge et al., 2002; McLennan et al., 2003; Najman, 2006; Sun et al., 2008; Fergusson et al., 2009; Veevers and Saeed, 2009; Bahlburg et al., 2010). Recent improvements of the geological knowledge of the Ceará Central Domain (CCD) in the Borborema Province has led to a better understanding of the tectonic architecture of this crustal segment and its role in West Gondwana assembly during the late Neoproterozoic (Caby and Arthaud, 1986; Fetter et al., 2003; Castro, 2004; Arthaud et al., 2008; Santos et al., 2008, 2009). Gondwana Research 18 (2010) 497–513 ⁎ Corresponding author. Tel.: +55 85 38780200; fax: +55 85 38780235. E-mail addresses: caegeo@gmail.com, cganade@fo.cprm.gov.br (C.E.G. de Araújo). 1342-937X/$ – see front matter. Crown Copyright © 2010 Published by Elsevier B.V. on behalf of International Association for Gondwana Research. All rights reserved. doi:10.1016/j.gr.2010.02.001 Contents lists available at ScienceDirect Gondwana Research journal homepage: www.elsevier.com/locate/gr