The main objective of this drilling fluid analysis was the detection of inflows of formation fluids. Therefore different gases dissolved in the drilling mud were measured continuously and automatically at drill site with three different methodes (Fig.: KTB-Report 92-2 page C13). The operation principles of the mass spectrometer and the gaschromatograph have been explained by STROH et al. (1988) and FIGGEMEIER et al. (1991). The principle of radon determination is published by ERZINGER et al. (1992).
In the laboratory, the gamma radiation is measured by a sodium iodtite (NaI) scintillation detector (cores and cuttings) and by a germanium (Ge) semiconductor detector (cuttings). The cuttings are measured in air tight Marinelli-beakers with a volume of 250 cm3. For the core measurements a special, automatically operating equipment with three NaI detectors is used. A description of this apparatus is given in Wienand et al. (1989). The principle of measurements with the Ge-detector is described by Bücker et al. (1991).The measured spectra are calibrated by a standard of Luvarovite (NIM-L, South African Bureau of Standards). The influence of the local terrestrial radiation on the measurements has been corrected. Especially for the core measurements a calibration procedure has been performed for geometric corrections (core diameter and length). In general, a measuring time of 12 h for the NaI-detector and 2 h for the Ge-detector was chosen.
The magnetic susceptibility is measured by an inductive AC device (BARTINGTON). The sample is placed inside a coil which generates an alternating magnetic field. The applied frequency is 460 Hz (cuttings, 25.4 mm mini cores), 565 Hz (cores) or 1470 Hz (15 mm mini cores) respectively. A shift in the oscillator frequency is a measure for the magnetic susceptibility of the sample. The applied magnetic field strength is 80 A/m (RMS) and appr. 2 times the total earth magnetic field strength in the KTB area (=38 A/m). The measurement field is lower than the field which is necessary for magnetic saturation and allows therefore to measure the initial susceptibility. The used sensors are insensitive to the electrical conductivity of the samples. Except the determination of the temperature dependent susceptibility, all measurements are done under surface conditions (room temperature and atmospheric pressure).
Cuttings were crushed in a tungsten carbide ball mill for 25 min; while core samples were crushed in a tungsten carbide jaw breaker and then processed in the same way as the chip material. The resulting powder samples (max 0.06 mm size) were dried at 105°C, 3 gr selected and mixed with 2.5% Moviol solution and finally pressed under 40 kN into alumina rings. These standardized pellets were used for both, XRD and XRF measurements. For the determination of major and trace elements a fully automated wavelenght-dispersive XRF device (SIEMENS SRS 303 AS) was used in the field laboratory. The standard measuring operation comprised 11 major elements (SiO2, TiO2, Al2O3, Fe2O3 total, MnO, MgO, CaO, Na2O, K2O, P2O5, S) and 12 traces (Rb, Sr, Y, Zr, Nb, Cr, Ni, Zn, V, Cu, Th, U). Element concentrations were calculated by setting up calibration curves computed with more than 40 international natural rock standards.
Cuttings were crushed in a tungsten carbide ball mill for 25 min; while core samples were crushed in a tungsten carbide jaw breaker and then processed in the same way as the chip material. The resulting powder samples (max 0.06 mm size) were dried at 105°C, 3 gr selected and mixed with 2.5% Moviol solution and finally pressed under 40 kN into alumina rings. These standardized pellets were used for both, XRD and XRF measurements. For the determination of major and trace elements a fully automated wavelenght-dispersive XRF device (SIEMENS SRS 303 AS) was used in the field laboratory. The standard measuring operation comprised 11 major elements (SiO2, TiO2, Al2O3, Fe2O3 total, MnO, MgO, CaO, Na2O, K2O, P2O5, S) and 12 traces (Rb, Sr, Y, Zr, Nb, Cr, Ni, Zn, V, Cu, Th, U). Element concentrations were calculated by setting up calibration curves computed with more than 40 international natural rock standards.
Cuttings were crushed in a tungsten carbide ball mill for 25 min; while core samples were crushed in a tungsten carbide jaw breaker and then processed in the same way as the chip material. The resulting powder samples (max 0.06 mm size) were dried at 105°C, 3 gr selected and mixed with 2.5% Moviol solution and finally pressed under 40 kN into alumina rings. These standardized pellets were used for both, XRD and XRF measurements. For the determination of major and trace elements a fully automated wavelenght-dispersive XRF device (SIEMENS SRS 303 AS) was used in the field laboratory. The standard measuring operation comprised 11 major elements (SiO2, TiO2, Al2O3, Fe2O3 total, MnO, MgO, CaO, Na2O, K2O, P2O5, S) and 12 traces (Rb, Sr, Y, Zr, Nb, Cr, Ni, Zn, V, Cu, Th, U). Element concentrations were calculated by setting up calibration curves computed with more than 40 international natural rock standards.
Cuttings were crushed in a tungsten carbide ball mill for 25 min; while core samples were crushed in a tungsten carbide jaw breaker and then processed in the same way as the chip material. The resulting powder samples (max 0.06 mm size) were dried at 105°C, 3 gr selected and mixed with 2.5% Moviol solution and finally pressed under 40 kN into alumina rings. These standardized pellets were used for both, XRD and XRF measurements.For the determination of major and trace elements a fully automated wavelenght-dispersive XRF device (SIEMENS SRS 303 AS) was used in the field laboratory. The standard measuring operation comprised 11 major elements (SiO2, TiO2, Al2O3, Fe2O3 total, MnO, MgO, CaO, Na2O, K2O, P2O5, S) and 12 traces (Rb, Sr, Y, Zr, Nb, Cr, Ni, Zn, V, Cu, Th, U). Element concentrations were calculated by setting up calibration curves computed with more than 40 international natural rock standards.
In the complete KTB-VB and in in the KTB-HB down to a depth of 3003 m the gas phase was released and collected by twirl degassers attached in front of the mud shakers. This open system led to gas losses as well as air contamination. Therefore results obtained down to this depth have only qualitative character. After casing the KTB-HB to a depth of 3003 m a bypass system was installed at the BOP (blow-out preventer) 50 cm below the flow line. A constant part (about 100 l/min) of gas-bearing drill mud is pumped through the bypass directly to a twirl degasser which is isolated against atmosphere. To prevent air contamination or sucking off drill mud the pressure in the gas trap is balanced by charging argon. The released gas phase is completely sucked off and led through a heated hose (in order to prevent water condensation or freezing) to the logging unit and there parallel to the measuring systems gaschromatograph, mass spectrometer and radon logging device.
In the complete KTB-VB and in in the KTB-HB down to a depth of 3003 m the gas phase was released and collected by twirl degassers attached in front of the mud shakers. This open system led to gas losses as well as air contamination. Therefore results obtained down to this depth have only qualitative character. After casing the KTB-HB to a depth of 3003 m a bypass system was installed at the BOP (blow-out preventer) 50 cm below the flow line. A constant part (about 100 l/min) of gas-bearing drill mud is pumped through the bypass directly to a twirl degasser which is isolated against atmosphere. To prevent air contamination or sucking off drill mud the pressure in the gas trap is balanced by charging argon. The released gas phase is completely sucked off and led through a heated hose (in order to prevent water condensation or freezing) to the logging unit and there parallel to the measuring systems gaschromatograph, mass spectrometer and radon logging device.
In the complete KTB-VB and in in the KTB-HB down to a depth of 3003 m the gas phase was released and collected by twirl degassers attached in front of the mud shakers. This open system led to gas losses as well as air contamination. Therefore results obtained down to this depth have only qualitative character. After casing the KTB-HB to a depth of 3003 m a bypass system was installed at the BOP (blow-out preventer) 50 cm below the flow line. A constant part (about 100 l/min) of gas-bearing drill mud is pumped through the bypass directly to a twirl degasser which is isolated against atmosphere. To prevent air contamination or sucking off drill mud the pressure in the gas trap is balanced by charging argon. The released gas phase is completely sucked off and led through a heated hose (in order to prevent water condensation or freezing) to the logging unit and there parallel to the measuring systems gaschromatograph, mass spectrometer and radon logging device.
