(Fig.10)
The major research themes agreed upon after long-lasting discussions are：
* the nature of geophysical structures and phenomena; that is, we wanted to calibrate the geophysical deep-sounding methods to understand for example the crustal stress field and the brittle-ductile transition;
* study the thermal regime and heat transfer processes;
* investigate fluids in the crest, and of course
* understand and study the properties and evolution of the basement in that area.
(Fig.11)
This ambitious scientific program was realized by an integrated evaluation and interpretation of data from three different sources：
* A field lab which was established at the drill site which was in fact a very modern research institute;
* by a large variety of borehole experiments and borehole measurements; and
* by a large number of individual specialized research projects carried out at universities and other research institutions.
Altogether about 470 scientists from 12 countries have been involved in this program, with more than 300 individual research projects. The results of the KTB program have been summarised in a special volume of the Journal Geophysical Research in August 1997.
(Fig.12,13)
Since the pilot hole was completely cored, a core spotting took place in the main hole with a newly developed large-diameter coring tool. With this instrument large diameter cores up to 5 meters in length with a diameter of 25 centimeters were taken at a number of intervals.
Due to a newly developed drilling fluid system, a real break-through could be achieved in the analysis of cuttings, rock flour, drilling fluid and gases released from the drilling fluid. All these parameters were continuously measured with a large number of different methods.
(Fig.15)
I just want to show you the concept of gas analysis. Twelve gas components were determined routinely every 3 minutes quantitatively with this gas mass spectrometer and a chromatography system which was used for the hydrocarbons, and a special device for the continuous analysis of the radon content.
(Fig.16)
A number of borehole measurements were carried out. This Figure shows the electrical resistivity of the borehole televiewer.
(Fig.17)
Altogether, according to the experience from the pilot borehole, a combination of a number of instruments were applied, so we have a continuous record of the in situ properties of the drilled basement section. Even at very high temperatures there were a number of instruments available which worked excellently.
