The passage of Hurricane Donna (September 9-10, 1960) across south Florida, an area where details of the pre-storm sea floor were well known, enabled the recognition of widespread storm effects. The recognition of these storm effects led to the conclusion that a significant part of marine sedimentation records the geologic work of large storms.

Specific storm effects were as follows: (1) formation of large quantities of boulder-size rubble by the action of surf on corals at the platform edge; (2) transportation of all sizes of material away from the open sea toward the platform interior; (3) stranding of layers of carbonate mud over wide areas on the supratidal flat (above the normal high tide line).

The amount of boulder-size rubble formed by hurricane surf on platform-edge reefs far exceeds the amount produced by day-to-day processes of death and deterioration. Each large storm adds an increment to the building of the rubble accumulations.

The large extent of supratidal flats is due to the ability of storm tides to strand sediment over large areas, the inaccessibility of the supratidal flats to processes that could rework its sediment into adjacent marine environments, and the supply of the supratidal flat sediments at the expense of adjacent marine sediments that compete with it for a place in the geologic record. These factors help explain the large amount of supratidal sediments in some ancient rocks.

Interesting negative aspects of hurricane's effects were that: (1) mound-type accumulations of muddy sediment were not eroded by storm wave or tidal currents, and (2) the sediment-laden waters resulting from the stirring of bottom sediments into suspension by the storm waves and currents did not give rise to effective turbidity currents.

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