Estratigrafía y desarrollo tectosedimentario de los sedimentos terciarios en los alrededores de la Sierra de Hualfín, borde suroriental de la Puna, Catamarca, Argentina

tertiary sediments, outcropping around the hualfín-las cuevas range, catamarca province, argentina (fig. 1) reveal 3,000 m of alluvial continental clastic sediments. previous work includes many studies of this area, mainly motivated by the exceptional mammalian fauna the sediments contain (stahlecker, 1926 en riggs y patterson, 1939; cabrera, 1937, 1944; pascual y odreman rivas, 1971; marshall et al., 1979; marshall y patterson, 1981; butler et al., 1984; allmendinger, 1986; bossi et al., 1987, 1993, 1994; flynn y swisher, 1995; gavriloff et al., 1998; powell et al., 1998; esteban y nasif, 1999; esteban et al., 1999). detailed sedimentary facies analysis, provenance and compositional studies in sandstones and conglomerates, petrology and shale mineralogy and paleontologic studies were made in the sedimentary succession (muruaga, 1998). the lithostratigraphic scheme and its correlation with other units defined for adjacent areas are shown in figure 2. in the study area, the hualfín formation is defined as the basal unit (lower cretaceous) of the tertiary sediments. the overlying formations belong to the santa maria group (middle miocene to pliocene), having a stratotype at the santa maria valley (bossi y palma, 1982), including the las arcas, chiquimil, andalhuala and corral quemado formations. the chiquimil formation is divided into three members in the puerta de corral quemado-villavil area, now formally named the los ba？os (lower), el áspero (middle) and el jarillal (upper) members. two sedimentation settings have been distinguished (muruaga, 1998). the first, 3,500 m thick, dominated by braided river fluvial plain (rio villavil section, fig. 3 and 4) and the other of 2,300 m thick, by alluvial fans and close to the basin border (el durazno section, fig. 5). the paleocurrents and provenance data (table 3) indicate that the puna block and altohuasi-culampajá and papachacra ranges were the source areas of the neogene sediments in the hualfín basin. the sedimentary f