Heritage Cases

The proposed exploration programme is designed to evaluate the distribution of heavy mineral sands in the PR area and to ascertain the extent and grade of the deposits both vertically and laterally. Marine mineral sands exploration relies heavily on non-invasive geophysical prospecting activities. Initially this will involve a review of existing information and past survey results for these potential heavy mineral deposits. The prospecting will then follow several phases from grab sampling to geophysical surveys. If this work indicates potential, a vibracoring programme will define grade and tonnages of specific areas. Numerous prospecting and feasibility studies have been conducted on the Geelwal-Karoo heavy mineral sand deposits over the years. Results of the initial geological evaluation of the deposits have been published in MacDonald & Rozendaal (1995). Past information sources will be reviewed to provide a context for interpretation of results conducted under this application. The significance and grade of the Geelwal beach deposits has indicated the offshore potential for heavy mineral sands in the sea floor sediments. This specialist prospecting method involves work being undertaken from aircrafts and survey vessels using remote sensing techniques. No surface disturbance will take place during this phase and therefor no rehabilitation will be required. The size of the grab samples are considered very small and would not impact on the continuously recycled movements of the sea floor sediments. The prospecting activities will consist of the following phases: • Phase 1: Literature Study (Estimated Duration 1 year) • Phase 2: Geophysical Survey (Estimated Duration -1 year) • Phase 3: Grab sampling and analysis. (Estimated duration 1 year) • Phase 4: Detailed Geophysical Surveys. (Estimated duration 2 years) The geophysical survey will be in the form of a low level airborne magnetic survey. The results from this will identify potential enriched areas within the PR area that can be targeted for specific sampling. Following the outcome of the Phase 2 programme, grab samples of the sea floor sediments will be taken. The areas of high magnetic potential will be sampled using a small grab lowered from a boat. The samples will be no more than 20 kg each. Sample sites will be surveyed and the actual samples will be analysed in detail to define the mineral types and ratios. With the combined earlier exploration results a detailed geophysical survey will be undertaken. A combination of single beam bathymetry, side scan sonar and boomer sub bottom profiling will be recorded from a survey vessel/boat. The results will indicate sea floor sediment types, thickness, distribution and concentrations of heavy minerals.