High temperature logging has to this date mostly 
involved temperature and pressure measurements 
using mechanical and digital memory tools. Other 
physical parameters for reservoir evaluation have been 
obtained during drilling when the well can be cooled 
down using cooling water at the drill site. With more 
frequent high temperature geothermal utilisation and 
drilling to even higher temperatures (e.g. supercritical), 
the need to upgrade existing instruments and methods 
for extended tolerance to even more volatile conditions 
has become more urgent. Such instruments and 
methods could then be operated without the need 
of cooling and can in some cases be the only methods 
available for use if a well cannot be cooled down, due to
excessive heat or lack of cooling medium. A brief 
overview of the current status of high temperature 
logging conditions will be given, along with discussions 
on the required parameter space, which can depend on 
factors such as formation types and well fluid chemistry. 
Tool manufacturing limitations are discussed (material,
connections and electronics) along with wellhead design 
considerations, that would allow logging even at high 
wellhead temperatures and pressures.

Grensasvegur 9
Reykjavik,
Iceland