Revisión de la Zona de Hoekaspis schlagintweiti Harrington y Leanza, Ordovícico del Noroeste argentino

WAISFELD, B.G.

Tarija

Congreso; XII Congreso Geológico de Bolivia; 1996

The well known "Hoekaspis schlagintweiti" zone from Northwestern Argentina is here reviewed from stratigraphic viewpoint. The lower Llarvirn age of the "Hoekaspis schlagintweiti" zone is here modified. In view that Hoekaspis sp. nov. (=H. schlagintweiti sensu Harrington y Leanza, 1957) is associated to a lower Caradoc conodont fauna (cf. Albanesi y Rao, in press) in the Santa Gertrudis Formation (Sierra de Mojotoro, Salta Province), the "H. schalagintweiti" zone is restricted to that age. The occurrence of Hoekaspis sp. nov. in the Los Colorados-Chamarra area (western flank of the Cordillera Oriental, Jujuy) substantially extend the record of this taxon in Northwestern Argentina. Hoekaspis sp. nov. bearing units in the Sierras Subandinas and Cordillera Oriental (i.e. Capillas, Santa Gertrudis, and the upper part of Sepulture formations) are regarded to the lower Caradoc. Furthermore, potential chronologic equivalence with Bolovian units yielding Huemacaspis Pribyl y Vanek, as well as Hoekaspis matacensis (Hoek) is here discussed.