Francisco Pascasio Moreno, born in Buenos Aires in 1852, was attracted to the natural sciences from an early age. Between 1873 and 1880, he led 4 expeditions to the Patagonian hinterland. In 1896, after further years of research in the Andes, he accepted the position of "Perito" [official Expert] for the Boundary Commission, representing Argentina's interests in determining the frontier with Chile.

Moreno's original map, on which this one was based, was published in Buenos Aires in 1879. Survey data for the Río Santa Cruz were taken from Fitzroy (1834). In addition to Moreno's route, this map includes parts of Musters (1869), Lista (1878), and several Indian trails.