Buried reef structures in the Lennard Shelf, Canning Basin, Western Australia

Buried Upper Devonian reef has been found in Meda No. 1 borehole in the Lennard Shelf, Canning Basin. Frequency analysis made on seismic-record sections across the structure indicates an increase in the frequency of seismic reflection above the structure. The frequency increase is interpreted as indicating thinning of sedimentary layers caused by differential compaction commonly found above a reef. Analysis of a further sixteen selected seismic-record sections containing features suspected to be reef structures shows the presence of similar frequency anomalies on four of the seismic sections, and is suggestive of a further four buried reef structures in the Lennard Shelf.