Observing these features in Saddleworth is relatively easy once one knows the basic form of evidence to look for. The growth of a delta front is created by the continuous deposition of sediment from a landmass onto the submarine slope. A modern analogue would be the Egyptian River Nile delta or the delta on the River Ganges, Bangladesh. Outflow from a river gives the shallow waters a uni-directional current flow and typically beds (or layers) of sediment drape over each other as they accumulate. (See Fig 4 below)


Fig 4

These deltaic flow directions and sediment accumulation patterns can be seen in the photograph below which was taken around the Dovestones Reservoir region. Flow can be deduced as from left to right as classic ‘S’ curve prograding bed features can be seen. Also evident from this photograph is the evolution of the past submarine slope deposits with the upward variation in bed thickness (7 beds in all with 3 thinner strata at hammer-head level). (See Fig 5 below)


Fig 5

The figure 6 below explains the development of the cross-bedding seen in the photograph above.


Fig 6

Exposures like this are common and a larger example can be seen below (Fig 7). Flow is again left to right in the ancient delta.


Fig 7


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