X=Ray fluorescent chemical analysis down borehole - using nip diode in solid ionisation chamber dependent upon emission voltage

摘要

The source of excitement of the X-F by means of x or gamma photons and the detector of the x-rays from the element or the collection of elements being investigated, in a process of chemical analysis down a borehole, are selected so as to maximise simultaneously the x-ray fluorescence of known characteristics and the number of charges corresponding to this radiation recorded by the detector. It is possible to analyse the chemical elements down a borehole without it being necessary to extract cores for examination at the surface. The detector used for the increasing of the efficiency of the process is an n.i.p. diode based on Si compensated with Li. A solid ionisation chamber based on HgIn is used when the energy is 0.5-50 KeV whilst an ionisation chamber based on Te or Cd is used when the fluorescent x-rays emitted by heavy elements and the value is 10 - 100 KeV.