THE COMBINED USE OF LANDSAT TM IMAGE AND VECTORIAL
INFORMATION APPLIED TO THE CHARACTERIZATION
OF THE TULUM VALLEY, SAN JUAN, ARGENTINA
Graciela Salinas de Salmuni
Ruben Porcel
Marina I. Lundi
Marcelo Roldan
Universidad Nacional de San Juan
Faculdad de Ingenieria
PREMA - Procesamiento de Information de Recursos Naturales y Medio Ambiente
Departamiento de Ingenieria de Minas
Av. Libertador San Martin 1109 (Oeste)
5400 San Juan, Argentina
ISPRS Commission VII / Working Group 9
ABSTRACT
The city of San Juan is located in the North-west of Argentina, within the Tulum valley it was originated
from San Juan River which has its source in The Andes Range. This river is W-E direction along a
deep and wide stream channel, spreading in several branches causing a fan of about 10 km wide.
After crossing the city, the river reaches its local base at Guanacache and Rosario lagoons and finally
passing through a meandering area forming isolated lagoons.
The climate in the ecosystem of Tulum is of the subtropical torrid desert type. There soils on the former
fluvial plain. They are of sandy composition, overlaying a lime-argillaca bed, with good drainage,
although in some zones the water tableis near the surface, causing loss of growing surfaces. There are
also saline-alkaline soils which reach, in parts, the characteristics of salinas forming the southern
boundary of the valley, it can also be noted the presence dune areas, distributed all over the valley. The
main crops are vine, olives, fruits and vegetables.
From the structural point of view, the valley is a tectonic depression bounded to the by the Andes to the
west and by the Sierra Pampeanas precambric basement to the east. The faulting direction is coincident
with the NNE - SSW regional orogeny.
When considering the geographic, geological, geomorphological, hydrological and climate features of
Tulum Valley, it can be seen that there are areas where the environmental analysis should be a basic
element for urban and rural design planning and, consequently, for a better performance of the local
economy.
This paper reports on the advantages of integrating the results of digital processing Landsat TM image
combined with vectorial information from existing maps.
Several digital image procedures were used, including image enhancements with both sing and color
combination, achieving the identification on the image of structural, lithological an geomorphologic
features.
Color combinations were use to generate each of the composites of the 7 bands of the image in order to
remark different features, like soil degradation, land use and vegetation types, and also for urban features.
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