Popis: |
An overview of early studies on heavy minerals in the southern North Sea is presented, followed by the state of the art as regards seabed sediments mapping and (sub)recent sediment dynamics. The aim of this study is to relate the findings of Baak's (Regional petrology of the southern North Sea. Ph.D. Thesis, Leyden University, H. Veenman and Sons, Wageningen, 128pp) heavy mineral study and some later mineral studies to the results of more recent seabed sediment mapping activities and studies on sub-recent sediment dynamics. Baak's findings could not be appreciated properly at the time as knowledge in the other fields was almost non-existent. His five-fold subdivision of seabed sands and their geological significance is interpreted with the extant knowledge regarding geological mapping and seabed dynamics. Compared to the two fields last mentioned, heavy mineral studies remain useful in tracing relicts of former surface deposits no longer mappable and in tracking down the fate of material derived from eroded seabed deposits. The symbiosis between seabed mapping, (sub)-recent dynamics and mineral studies generates a very strong tool for the unravelling and reconstruction of the dynamic history of shallow shelf and coastal sands. |