Los estromatolitos del Precámbrico tardío de los alrededores de Caborca, Estado de Sonora; parte 1, Reconstrucción de Jacutophyton Shapovalova e interpretación paleoecológica preliminar

Abstract

The fossil stromatolites of the Gamuza Beds, south of Caborca, Sonora, were discovered in 1941 and afterwards assigned to "Collenia" or ''Cryptozoon" in a tentative inanner. The finding of Conophyton and Jacutophyton at two localities allows to corroborate the previous assignation of the Gamuza Beds to the Late Precambrian, at least up to the uppermost level with Jacutophyton. The Units 10 to 12 of the Gamuza Beds (sensu Anderson et al., 1978) do not carry stromatolites and lack other guide fossils. Their attribution to the Precambrian is therefore tentative. Excellent outcrops of stromatolite bioherms in the area allow the reconstruction and paleoecological interpretation fundamental in local and regional correlation (basin analysis). The bioherms developed in a marine environment and, at least temporally, at the subtidal zone and below the wave base.