The formations of this region are essentially metamorphic Granit-Gneissic of which the term granitic is descended of the granitization-migmatization of Kimezien. Two tectonic periods have been demonstrated by double schistosities noticed to the level of the micas. The geochronology of these formations will be able to bring more precision on the age of these formations and that has the end will confirm or will invalidate the thesis to evoke in this survey.
This cartographic survey has been done from the samples of cores of polls achieved on longitudinal and transverse profiles as well as by the modelling, appropriated precisely in the concession of the mining of Bakwanga on the massif 12.
Of these data of polls, we could achieve a cartographic survey and deduct the structure of this massive kimberlitic under survey.
Let’s note that most polls on this massif, met the sand, sandstone, the epiclastic kimberlite, the xenokimberlite, the massive kimberlite and the limestone.
In a general manner, to part the limestone, the dolomite, sandstone and the sand, three facies kimberlitics has been put in evidence in this publication and it, according to the percentage in kimberlitics elements, it is about of:
- The kimberlite very tender epiclastic (0-25% of kimberlitic elements).
- The little strengthened xenokimberlite (25-50% of kimberlitic elements).
- The massive kimberlite (beyond 75% of kimberlitic elements).