Most of the asphaltite veins in this area are located around the volcano Tromen, with preferential direction NE-SW, even tough in its proximity the veins have more radial directions. (Cobbold et al, 2011). According to observations of these authors, the veins get thinner as they get away from the volcano, and in some cases they present branches.
However, the maximum thicknesses (exceptionally up to 10 meters) can be found when the wall rock is very resistant to the fracture, which is the case of the formations Tordillo, Avilé or Mulichinco, or Grupo Neuquén. (Cobbold et al, 2011).
Several veins in the area Laguna Auquilco are set in sandstones of the formation Tordillo, among them La Salvada, as well as the veins of the group Curaco and La Carrascosa located a few kilometers to the east of the first one. Actually, the asphaltite vein La Salvadais exposed in the surface in pelite box of the formation called Vaca Muerta and its structure can be followed to the NW over rocks of the same unit. Reason why the schematic sections presented by Danderfer (2006) with the location of the suggested explorations wells place in all cases the formation Vaca Muerta as the outcropping entity closest to surface,
which is consistent with the reality.
Danderfer also made a valid observation referring to the possibility that the structure of the vein La Salvada gets thicker when going deeply trough more fragile rocks belonging to the formation Tordillo, which agrees with recent assertions made by Cobbold et al (2011). Maybe in order to complete the diagnosis of the position of the explorations, it would be good to complement the range of possibilities presented by the information of the magnetometric research done by Danderfer (2006), which included a significant amount of measuring or control points. The graphic representation of these points shows a clear alignment that suggests the continuity of the vein structure La Salvada in direction NW-SE.
Before deciding the execution of proposed explorations, the characteristics of the veins filling should be confirmed by means of geoelectric profiles, since the magnetometry gave some information about the presence of discontinuations in the subsoil (faults, fractures, lithologic contacts) but said very little in relation to their filling and thickness. The experience that took place in the south-west slope of the volcano Auca Mahuida in the area of the asphaltite veins Auca Mahuida and La Escondida should also be considered. There, the magnetometry indicated continuity relations between both veins while the geoelectric profile clearly showed the absence of filling in those fractures.