February 24, 2004
Further Interpretation Of Drilling Results
TORONTO, ONTARIO - Tsodilo Resources Limited (TSX Venture Exchange: TSD) are pleased to announce an update on the Company's Ngamiland diamond exploration program, including a further interpretation of their geophysical survey and reverse circulation drilling results on the A37 and A12 kimberlites.
Exploration Program Summary
Tsodilo's exploration program consists of a number of individual projects. The most important of these are:
1. Evaluation of the recently discovered A37 and A12 kimberlites in the Nxau Nxau kimberlite field, and the investigation of further magnetic targets which, it is believed, could reflect a significant extension of this field to the south.
2. Follow-up of further magnetic targets in the Guma area in the east of the licence block to locate the source of unexplained Kimberlitic Indicator Minerals (KIMs) recovered by our soil sampling programs in this area.
3. Follow-up of magnetic targets associated with unexplained KIMs in the south of the ground held by the company's Botswana-registered 75% held subsidiary, Newdico.
4. Investigation of bulls-eye magnetic anomalies in the Prospecting Licences recently acquired by the company's wholly owned subsidiary, Gcwihaba Resources. This ground is located to the south of the Newdico Licences.
Evaluation of the A37 and A12 Kimberlites
The evaluation of the recently discovered A37 and A12 kimberlites in the Nxau Nxau cluster represents of the most advanced of the company's projects.
Additional chemical analyses for Niobium and Nickel in drill samples confirms our previous cautiously expressed view that the drilling had indeed intersected kimberlite crater facies sediments. Essentially, kimberlites tend to be relatively enriched in Niobium (Nb) and Nickel (Ni) relative to most other rock types. When a kimberlite erupts, particularly if it encounters groundwater and explosively fractures the country rock, a mixture of kimberlite material and country rock fragments are blown into the air to form an unstable cone around the kimberlite. This mixture of kimberlite and country rocks then collapse back into the crater to form the crater sediment sequence. The lowermost crater sediments are formed by unstable debris flows ("landslides") giving rise to coarse, poorly-sorted basal deposits while the waning phases of sedimentation in the crater are finer clays settling out of the crater lake giving rise to a series of shales and mudstones. Chemically, the crater sediments will reflect this mixture of reconstituted country rocks and kimberlite tuffs. Our drilling and chemical results indicate deep weathering of these sediments, which has led to strong leaching of the elements that are typically concentrated in kimberlitic crater sediments.
The gravity and magnetic data from ground surveys over the A37 kimberlite are interpreted to indicate that there is a major kimberlitic crater and at least two closely associated subordinate craters with a number of kimberlite intrusive centres. It is therefore similar to many of the world's large kimberlites in being a composite body. We estimate that the main A37 sediment-filled crater is some 1000m in length by 500 to 600m in width and that the total surface area, including the subsidiary basins to the east and north, is 80 -120 hectares. While further drilling will be needed to delineate the body with greater accuracy, it seems as though this will be the second or third biggest kimberlite found in the Republic of Botswana, the largest producer of diamonds, by value, in the world.
The drilling results therefore confirm our earlier geophysical interpretation of this composite kimberlite intrusion. The dolomitic limestone country rock probably contained considerable amounts of groundwater in solution cavities at the time of the kimberlite eruption. The very hot kimberlite, encountering this water, turned it to steam and resulted in a very large explosion that caused extensive fracturing of the dolomite in what is termed a "phreatic eruption". The large surface area of the resulting crater sediments and its flat, "champagne-glass" cross-sectional shape bear testimony to this event.
It should be noted here that there are several examples world-wide of very high-grade producing diamond mines where similar "phreatic eruptions" of kimberlite occurred. The Mbuji Mayi mine in the Kasai Province of the Democratic Republic of the Congo consists of an elongate group of 10 kimberlite pipes along a linear zone some 3,500 metres long by 800 metres wide and also erupted through dolomitic limestone country rock leaving a flat "champagne-glass" cross-sectional shape and extensive crater sediments. Other examples of the development of diamondiferous crater sediments are at the Argyle mine in Australia, the Lac de Gras kimberlite cluster and the Orapa mine some 500 Km. southeast of A37. The high grades associated with these kimberlites may indicate that the phreatic eruptive processes favour the preservation rather than the resorption of the diamonds.
Our drilling results indicate that the A12 kimberlite intruded through quartzite country rock, probably containing less ground water with a less explosive eruption and therefore differs from the A37 body in having a "carrot" shape, making it more similar to pipes elsewhere in southern Africa, and those in the Lac de Gras field in Canada.
Composite samples of drill chips from A12 and A37 have been collected and bagged for shipment to Canada where micro-diamond analyses will be done. The results are only expected by July 2004 when additional drilling of the two kimberlite occurrences will be planned on a systematic grid to better define the size and shape of the craters, their kimberlite pipe feeders and to collect sufficient samples for a reasonable estimate of the grade and value of any diamonds in the kimberlites.
Soil Sampling Program
Canadian geophysical contractors using a variety of different algorithms recently reprocessed our aeromagnetic data. This enhanced dataset was screened and over 100 bulls-eye magnetic targets selected for a follow-up sampling program. The targets are located in several areas where previous sampling has outlined isolated unexplained KIM anomalies. This suggests that they could represent at least three virgin kimberlite fields, as well as an extension of the known Nxau Nxau field to the south. Detailed KIM soil sampling over these anomalies will begin in March after the worst of the rainy season is over. Detailed gravity surveys and first-phase drilling of the positive targets will follow this program.
Tsodilo Resources is an international diamond exploration company engaged in the search for economic kimberlites at its Newdico and Gcwihaba projects in northwest Botswana. Tsodilo has a 75% stake in Newdico while Trans Hex Group, a South African diamond mining and marketing company, holds the remaining 25%. The recently granted southern "Gcwihaba Project" area is held by subsidiary Gcwihaba Resources and agreement in principal has been reached with SouthernEra Resources for their participation as to 50%. The exploration of both licence areas is managed by Tsodilo. The design and conduct of the Company's exploration program is the responsibility of Dr. Andrew Moore, a professional geologist registered with the South African Council for Natural Scientific Professions.
The TSX Venture Exchange does not accept responsibility for the adequacy or accuracy of this release.
FOR FURTHER INFORMATION PLEASE CONTACT:
James M. Bruchs -- President and Chief Executive Officer: E-Mail firstname.lastname@example.org
Dr. Andrew E. Moore -- Vice President, Exploration: E-Mail email@example.com
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