This paper discusses different aspects related to the andesite and obsidian availability and circulation at different moments of the occupation sequence in the Pueyrredón-Posadas-Salitroso (PPS) lake basin in the North, and the Burmeister-Belgrano lake basin in the South (Norwestern Santa Cruz Province, Argentine Patagonia).The distribution of raw materials -both in space and time- allows us to assert that potential regional circulation routes would have been affected differentially by the paleolakes present from the Pleistocene up until the mid-Holocene.The basis of the discussion is made taking into account sites from the Northeast coast of the Pueyrredón Lake, Cerro de los Indios 1 (central portion of the PPS basin) and Cerro Casa de Piedra 7 (near to the Burmeister lake). This investigation considers three moments that are contained at the sites studied: ca. 8000-4000 years BP; ca. 4000-2000 years BP; ca. 2000 years BP and later.