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Exploration Borehole


 
 Borehole Number: 105/25/K003/1A/H8
 
 Prospecting Company: De Beers Prospecting Botswana (Pty) Ltd
 Prospecting License No.: PL31/88
 Coordinates Type: WGS 84
 Coordinates Format: Decimal Degrees (DD)
 Coordinates: -22.704839 , 27.882721
 Location: Lerala
 
 Start Drill: N/A
 End Drill: N/A
 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: N/A
 End of Hole (Depth): N/A
 Hole Diameter: N/A
 
 Log Formation:
No.From (m)To (m) Log Formation
1.0 1Topsoil
2.1 2Topsoil with quartzite.
3.3 1260% pfg with first appearance of kimberlitic clay 40%.
4.12 19Kimberlite breccia with
5.23 2780% mafic Schist, 20% pfg.
6.27 281% aphinitic, textureless kimberlite, some phlogopites.
7.28 2970% dark green, aphanitic kimberlite, clay balls? of kimberlite
8.29 3120% pfg + Quartzite.
9.31 39Kimberlite 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 4130% blue kimberlite, phlog bearing not macrocrystic.
11.41 43100% quartz chlorite Schist.
12.43 47K clay coatings, qtz chl Schist,70%.
13.47 49Blue kimb + qz chl Schist much k.clay coatings.
14.49 50Green amorphous Silcrete, quartzite, no k clay.
15.50 51100% felsic gneiss + Quartzite.
16.51 59Chlorite Schist, felsic gneiss.
17.59 65Generally 100% chlorite Schist, felsic gneiss.
18.65 661% phlogopite kimberlite, generally 99% chlorite Schist, felsic gneiss.
19.66 69Felsic gneiss 40%, chl Schist + Amphiboliteibolite 60%.
20.69 77Kimberlite recognisable as brownish weathered, phlog bearing chips balls g k.clay 80%, 20% fg, chls.
21.77 795% kimb Fe oxides in chl Schists, felsication? Seen in some chips.
22.79 8120% kimb present as green, decomposed clay chips.
23.81 8520% kimberlite (as clay chips) incls of chl sch + Amphibolite.
24.85 875% kimberlite (as clay chips) incls of chl sch + Amphibolite.
25.87 8930% kimberlite (as clay chips) incls of chl sch + Amphibolite.
26.89 9020% kimberlite (as clay chips) incls of chl sch + Amphibolite.
27.90 9399% kimberlite (as clay chips) incls of chl sch + Amphibolite.
28.93 11193m 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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