Dear Sir/Madam,
I am Iulian Seba, an exploration geologist a with a large experience in various projects across Europe, Africa and US, working for various exploration projects.
I have a large experience in GIS, working with a lot of data, to interpolate or to use maps with data already interpolated.
I have feasible GIS solution for your project but there is a problem: I cannot see any coordinates (latitude, longitude) on the drawings. Usually they are marked on the margins but in this case...nothing.
Without these coordinates it is impossible to georeference the maps, placing them in an exactly geographical position.
Do you have more complete data about?
As a clue, the small green cross are the marks for the map grid. Knowing the position of this is possible to reference the maps and then working with the contours.
If a master map with the grids and coordinates figure is available, the problem can be solved.
Hooping that my skills are useful for your project I remain at your disposal for any other details.
Kind regards,
Iulian Seba