| Borehole Number: |
| Prospecting Company: De Beers Holdings Botswana |
| Prospecting License No.: PL31/88 |
| Coordinates Type: WGS 84 |
| Coordinates Format: Decimal Degrees (DD) |
| Coordinates: -22.704839 , 27.882721 |
| Location: Lerala |
| Start Drill: 0000-00-00 |
| End Drill: 0000-00-00 |
| Borehole Type: Exploration |
| Drilling Method: Core |
| Sample Type: Core |
| Depth of Surface Casing: N/A |
| Azimuth: Degrees |
| Hole Inclination: N/A |
| Collar Elevation: N/A |
| Borehole Water Strike: Metres |
| End of Hole (Depth): N/A |
| Hole Diameter: Millimetres |
| Log Formation: |
| No. | From (m) | To (m) | Log Formation |
|---|
| 1. | 0 | 1 | Topsoil |
| 2. | 1 | 2 | Topsoil with quartzite. |
| 3. | 3 | 12 | 60% pfg with first appearance of kimberlitic clay 40%. |
| 4. | 12 | 19 | Kimberlite breccia with |
| 5. | 23 | 27 | 80% mafic Schist, 20% pfg. |
| 6. | 27 | 28 | 1% aphinitic, textureless kimberlite, some phlogopites. |
| 7. | 28 | 29 | 70% dark green, aphanitic kimberlite, clay balls? of kimberlite |
| 8. | 29 | 31 | 20% pfg + Quartzite. |
| 9. | 31 | 39 | Kimberlite presence is often only as clay coatings to chips, presence of quartz - chlorite Schist gives logging problem espcially with estimating % inclusions section in rich basement inclusions. |
| 10. | 39 | 41 | 30% blue kimberlite, phlog bearing not macrocrystic. |
| 11. | 41 | 43 | 100% quartz chlorite Schist. |
| 12. | 43 | 47 | K clay coatings, qtz chl Schist,70%. |
| 13. | 47 | 49 | Blue kimb + qz chl Schist much k.clay coatings. |
| 14. | 49 | 50 | Green amorphous Silcrete, quartzite, no k clay. |
| 15. | 50 | 51 | 100% felsic gneiss + Quartzite. |
| 16. | 51 | 59 | Chlorite Schist, felsic gneiss. |
| 17. | 59 | 65 | Generally 100% chlorite Schist, felsic gneiss. |
| 18. | 65 | 66 | 1% phlogopite kimberlite, generally 99% chlorite Schist, felsic gneiss. |
| 19. | 66 | 69 | Felsic gneiss 40%, chl Schist + Amphiboliteibolite 60%. |
| 20. | 69 | 77 | Kimberlite recognisable as brownish weathered, phlog bearing chips balls g k.clay 80%, 20% fg, chls. |
| 21. | 77 | 79 | 5% kimb Fe oxides in chl Schists, felsication? Seen in some chips. |
| 22. | 79 | 81 | 20% kimb present as green, decomposed clay chips. |
| 23. | 81 | 85 | 20% kimberlite (as clay chips) incls of chl sch + Amphibolite. |
| 24. | 85 | 87 | 5% kimberlite (as clay chips) incls of chl sch + Amphibolite. |
| 25. | 87 | 89 | 30% kimberlite (as clay chips) incls of chl sch + Amphibolite. |
| 26. | 89 | 90 | 20% kimberlite (as clay chips) incls of chl sch + Amphibolite. |
| 27. | 90 | 93 | 99% kimberlite (as clay chips) incls of chl sch + Amphibolite. |
| 28. | 93 | 111 | 93m to EOH at 111m generally >90% inclusions of blue chlorite Schist and Amphiboliteibole kimberlite occurs as clay chips as discussed earlier. |
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