Cretaceous Research (2000) 21, 221–239 doi:10.1006/cres.2000.0209, available online at http://www.idealibrary.com on Palaeobiogeographic aspects of northeast Brazilian basins during the Berriasian before the break up of Gondwana 1 *A u tila A. S. Da Rosa and †Anto ˆ nio J. V. Garcia *Department of Geosciences, Federal University of Santa Maria (UFSM), Faixa de Camobi km 9, 97105-900, Santa Maria, RS, Brazil; e-mail: atila@base.ufsm.br †Sedimentary Geology Program, UNISINOS University, Av. UNISINOS 950, 93022-000, Sa ˜o Leopoldo, RS, Brazil; e-mail: garcia@euler.unisinos.tche.br Revised manuscript accepted 21 March 2000 A complete sedimentary analysis (lithofacies, palaeocurrent pattern, framework composition, biocorrelation) is presented for the northern margin of the Afro-Brazilian Depression, a large, shallow, northeast Brazilian basin that developed during the Berriasian prior to the separation of South America and Africa, the final break up of Gondwana. An understanding of the depositional systems has allowed an interpretation of the fossil record to be made in terms of palaeoclimate as the northern margin became wetter owing to a change in wind patterns. On a local scale, ponds and shallow lakes were surrounded by a rich fauna resembling present-day conditions in African savannahs. The regional behaviour of the fauna indicates migration routes that, although still not fully understood, seem to have changed from the situation that prevailed in southern Africa and South America earlier in the Mesozoic Era.  2000 Academic Press K W: palaeobiogeography; palaeoclimatology; Cretaceous; Berriasian; Gondwana break up; South Atlantic; Brazil. 1. Introduction Knowledge of northeastern Brazilian coastal and in- terior sedimentary basins has increased significantly during the last 30–40 years, mainly as a result of Petroleo do Brasil S/A (PETROBRAS) oil research. Since the work of Haroldo Erwin Asmus and Francisco Celso Ponte of PETROBRAS, the sedi- mentary succession in these basins has been sub- divided into three sequences (pre-rift, rift or syn-rift, and post-rift or drift). These sequences contain records of the stages of separation of South America from Africa during the break up of Gondwana, rift and post-rift being the most studied owing to the presence of sources of hydrocarbons in these rocks. Despite the presence of important local reservoirs in the pre-rift sequence in some basins (e.g., the Sergipe- Alagoas Basin; Garcia et al., 1998), this tectono- sequence is the most poorly studied. Academic interest in the pre-rift sequence is concerned with the representation of the Jurassic–Cretaceous boundary in Brazil. Scattered outcrops of the pre-rift sequence are present in the interior basins of the northeast (Figure 1). These sedimentary records represent the remains of what was once a great, shallow basin, the Afro- Brazilian Depression, originally defined by Ponte (1972), and re-evaluated by Garcia (1992), Garcia & Wilbert (1994) and Goldberg et al. (1996). Early Cretaceous orography of the Afro-Brazilian Depression (ABD) presented in palaeogeographic reconstructions by Ziegler et al. (1987) and Golonka et al. (1994) point to a narrow ‘lowland’, limited by ‘uplands’ parallel to the present coastal regions of Brazil and West Africa, according to Ponte’s (1972) first definition and subsequent papers (e.g., Ponte & Asmus, 1978). This paper presents an alternative palaeogeographic reconstruction of the ABD, detail- ing the palaeogeographic proposition in Garcia & Wilbert (1994) and Goldberg et al. (1996). As a result, our understanding of the palaeogeography and palaeoclimate is improved, which in turn enables the constraints on faunal and floral distribution in 1 Contribution to IGCP Project 381: South Atlantic Mesozoic correlations. 0195–6671/00/020221+19 $35.00/0  2000 Academic Press