The supply of sediment is one of the major variables responsible for the local variation in the geometric character of the sedimentary parasequence sequences sets and facies patterns of basin fill. Controls include climate, relief of fluvial drainage basin, lithology of substrate, and vegetative cover. Changes of sediment supply can be caused by tectonism and climate changes, often at a local level. The rate of and nature of sediment supply can bring about changes in accommodation.

Sediment supply for both clastics and carbonates vary commonly as a function of sea level position. Clastic rates will tend to be higher during relative sea level lows in response to higher rates of erosion of the more exposed inland interfluve areas. During the same lows carbonate accumulation rates will be high if the offshore basin is shallow enough, but non-existant on the exposed basin margin. The source of the clastic sediment is likely the updip uncoformities of the sequence boundary. Clastic accumulation rates are lower during transgressions and highstands in sea level. carbonates tend to fall in the offshore with rapid rises in sea level, but can keep pace with the sea level rise in the inner shelf lagoons. During highs in sea level the carbonates fill the inner shelf and prograde seaward across shallow shelves. carbonate turbidites are associated with the increase in slope of the basin margins during sea level highs but will be their most prolific when the upper part of the margin is exposed during sea level lows but and the down slope margin can become the main carbonate factory.

If a portion of the accommodation being produced by tectonic subsidence and eustasy is reduced, then a small increase in the rate of sedimentation is likely to cause the resulting parasequences into a forced regression of prograding clinoforms whose upper surface often undergoes diachronous erosion. This stacking pattern of parasequence sets is commonly produced in the early lowstand systems tract of shallow offshore basins.

In contrast, if the development of accommodation being produced by tectonic subsidence and eustasy increases then should the rate of sediment supply not able to keep pace with this increase of space then the resulting parasequences are likely to backstep retrogradationally over the earlier sedimentary section. This stacking pattern of parasequence sets is commonly produced in the transgressive systems tract. Commonly the upper layer of the transgressive systems tract is a condensed section which is associated with the mfs where it is overlain by the downlapping highstand systems tract. Sometimes the transgressive surface marking the base of the trangressive systems tract is immediately overlain by a condensed section that is in turn capped by the mfs.

Finally if the development of accommodation being produced by tectonic subsidence and eustasy matches the rate of sediment supply then the resulting parasequences are likely to aggrade and prograde over the earlier sedimentary section. This stacking pattern of parasequence sets is commonly produced in the highstand systems tract.

If sedimentation constantly outpaces the creation of accommodation produced by tectonic subsidence and eustasy then the resulting prograding clinoforms will build out in all the systems tracts, including the transgressive systems tract. If sedimentation rates are constantly low compared the creation of accommodation produced by tectonic subsidence and eustasy then the resulting sedimentary geometries will retrogressively backstep or onlap onto the basin margin in all the systems tracts, including the lowstand and highstand systems tracts.

The build out trajectory of the clinoforms developed at basin margins will tend to be low or close to horizontal if the rates of sediment supply match or slightly exceed the development of accommodation. If accommodation development is just exceeded by sedimentation supply rates then coastal build out trajectory will tend to become steeper offshore. If accommodation development exceeds rates of sedimentation supply then coastal trajectory builds back onto the land in a stepped manner. The steeper trajectory is favored by a small difference in the rates of accommodation development and sediment supply.