129. The authorization holder must carry out the well logs necessary to be able to define the lithology, porosity, type of the fluids present in each of the geological formations intersected by the surface casing to the well casing head and in depth, under the surface casing.
The holder must, in particular, carry out
(1) a gamma ray logging from the well casing head to the final depth of the wellbore;
(2) a neutron logging from 25 m under the well casing head to the base of the surface casing; and
(3) an electrical resistivity logging and a porosity logging from the base of the surface casing to the final depth of the wellbore.
In the case of an electrical resistivity or porosity logging, it must be carried out at least until a 70° angle has been reached in relation to the vertical.
The Minister may exempt the holder from the requirement to carry out certain well logs in the case of a production well or if the Minister considers that he or she already has sufficient data to characterize the reservoir or the sealing rocks.