oa Regional AEM Survey in NE Namibia

Regional surveys using the TEMPEST208 airborne electromagnetic system were acquired for the Geological Survey of Namibia in 2011. The TEMPEST208is the lowest cost airborne electromagnetic system available currently worldwide and was selected to test a cost- effective means of covering the country with AEM and particularly to map thickness of the Kalahari Sequence to open new areas for mineral exploration.

This review of the data acquired showed that;

• The TEMPEST208 system did have some noise problems but significant improvements could be achieved with minor system modifications.
• TEMPEST208 can map areas of thin (0-60 m), to medium (~100 m) and thick cover (>150 m) Kalahari Sequence. In areas of thin cover, conductors can be detected in the underlying basement. In areas of medium cover an estimate of thickness of the Kalahari (with LEI) is probably possible but in areas greater than 150 m the system generally did not appear to detect the base of the Kalahari.
• Comparison with detailed surveys done with standard TEMPEST and VTEM shows that TEMPEST208 detected most of the features seen in surveys by the more sophisticated system.
• The data will be useful for explorers selecting best areas for exploration particularly where the Kalahari Sequence is less than 60 m.