The geological structure of the Catoca it is complex and the mineralized body is subdivided into three different parts. The Central, up to 200m deep, is composed of vulcanogenic-sedimentary rocks (tufistic kimberlite).
The part that surrounds the chimney walls has the ring shape and is composed of kimberlites and rocks derived from them and represents the main industrial ore (porphyrical kimberlite). The central part of the mineralized body, below 260m, is composed of autolytic kimberlitic gaps. Up to a depth of 100m the average diamond content is unevenly distributed, the western part being richer than the eastern.
Embedding rocks are made up of gneiss. At a depth of 65 to 75m the rocks are represented by several species and solid monolithic material. The physical and mechanical properties of kimberlite, at the upper levels, reveal its low resistance, easy crushing and high self-disintegration.
Geological Prospecting and Geophysical Research
Geological activities at the level of the Kimeberlite Catoca include, follow these steps:
1. Analysis and processing of geological and geophysical information;
2. Geological, geophysical and mineralogical mapping;
3. Data collection with electromagnetic methods;
4. Magnetic survey;
5. Aerogeophysical survey;
6. Directional drilling;
7. Helical drilling;
8. Drilling of detonation wells;
9. Drilling of hydrogeological wells;
10. Profiling of wells;
11. Treatment of geological samples / core and large volume;
12. Mineralogical and petrographic analysis;
13. Geomechanical studies.
Catoca prospecting in:
- 1 . Concessions of Catoca, Luaxe and Vulege (Lunda Sul)
- Luemba, Luangue and Tchafua concessions (LundaNorte)
- Gango and Quitubia Concessions (Kwanza-Sul)