The Orapa Kimberlite field of Botswana is one of the world’s major diamond producing regions. Within this field, there are several small kimberlite pipes that have not been completely explored in terms of the lateral extent, depth and diamond potential. Two such pipes, BK54 and BK55, were found during a ground gravity and magnetic survey and subsequent drilling confirmed the presence of kimberlite material. To determine the physical properties of these pipes, their lateral extent, depth and thickness were estimated using a gravity and magnetic analysis and 2.5D and 3D modeling. Tilt derivatives of the magnetic data indicated that BK54 has a northwest-trending elliptical shape and BK55 has a roughly circular shape. Residual gravity anomaly maps indicate that BK54 does not have a density anomaly while BK55 is associated with a gravity maximum. 3D gravity and magnetic inversion modeling constrained by magnetic susceptibility measurements indicate that BK54 is smaller in volume than BK55 and neither pipe is thicker than 125 m. The difference in shape and the lack of a gravity anomaly over BK54 implies a different formation mechanism for each kimberlite pipe. While several mechanisms are suggested, BK54 may have formed by a more explosive eruption producing more tuffistic material in both the crater and diatreme facies. The gravity and magnetic analysis also found that the kimberlite pipes, while small, are larger in extent than determined by drilling and warrant additional drilling to determine their economic potential.

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The Okavango Rift Zone (ORZ) and Okavango Delta in Northwest Botswana are Earth's youngest continental rift system and largest inland delta. The delta and its underlying sediments record the effects of incipient rifting on the geomorphology and stratigraphy within the (incipient) southwestern arm of the East African Rift System in Botswana. Three open questions that we use river-borne seismic-reflection profile analyses to answer are (1) whether the Gumare fault extends across the delta, (2) whether the Gumare fault zone is a part of the ORZ, and (3) how wide is the ORZ. Our results suggest that the Gumare fault extends across the delta and is a part of the ORZ. Integration of our and pre-existing geophysical data also suggests that the southern section of the ORZ is more active than the northern section that we imaged, and at least 150 km of fault-related extension has occurred within the Okavango Rift Zone. These findings provide constraints on the present-day structural and stratigraphic configuration of the ORZ and OD, which is a fundamental first step towards reconstructing sedimentation and extensional patterns during the earliest stages of continental rifting.