-----

I got the geological maps from here:

http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/indice.htm

http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/28-k.jpg
http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/28-l.jpg
http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/29-k.jpg
http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/29-l.jpg
http://www.ingemmet.gob.pe/publicaciones/serie_a/mapas/30-l.jpg

-----

Got the satellite images from Google Earth

Zoomed into the desired area.
View->Grid

File->Save->Save Image

-----

In both cases below, once I got the jpg image, I cropped it to just the 
lat/long grid I wanted, and saved that version in the "cropped" folder.

-----

Renamed the files, so the filename shows the lat/long extents:

Geological Maps:
mv 28-k.jpg geo140s765w-135s760w.jpg
mv 28-l.jpg geo140s760w-135s755w.jpg
mv 29-k.jpg geo145s765w-140s760w.jpg
mv 29-l.jpg geo145s760w-140s755w.jpg
mv 30-l.jpg geo150s760w-145s755w.jpg

Satellite Maps:
mv 28-k_google.jpg sat140s765w-135s760w.jpg
mv 28-l_google.jpg sat140s760w-135s755w.jpg
mv 29-k_google.jpg sat145s765w-140s760w.jpg
mv 29-l_google.jpg sat145s760w-140s755w.jpg
mv 30-l_google.jpg sat150s760w-145s755w.jpg

-----