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Granule ripples are a common feature of most dunefields, yet they have seldom been recognized in ancient deposits. Although granule ripples are common in erosional settings, such as windward slopes of dunes, or scour surfaces in interdunes, they nevertheless migrate laterally and leave distinctive deposits that can be recognized in ancient rocks. These deposits have characteristics of ‘type B’sand sheet deposits, including: ‘poured‐in’texture; curving ripple trough; tangential, coarse‐grained foresets; irregular silty layers; well‐sorted coarse and fine layers (either horizontal or within foresets); and fine layers in ripple troughs. Wind tunnel experiments suggest that under low‐velocity wind conditions, granule ripples grow to a significant degree as parasites dependent on saltation of fine sand grains whose impact moves the larger grains of the granule ripple. Although the depositional surface of granule ripples is commonly coated with a layer of coarse grains, this is in most places only a few grains thick. Underlying deposits commonly have a poorly sorted, or ‘poured‐in’texture. This texture results from an admixture of fine grains that fall among the spaces between the larger grains during deposition.

The Jafurah sand sea of the Eastern Province of Saudi Arabia extends along the Arabian Gulf coastline from Kuwait in the north to the Rub Al Khali in the south, a distance of about 800 km. Sand drifts southward to south‐eastward from regions of high wind energy in the north to low wind energy in the south. The aeolian landscape is zoned, with areas of deflation, transport and deposition from north to south. Drift rates in the zone of transport, near Abqaiq, range from 2 m3 m‐w‐1 yr‐1 on sabkhas, to 29 m3 m‐w‐1 yr‐1 on the crests of dunes. Average drift rates of approximately 18 m3 m‐w‐1 yr‐1 observed during the study can cause about 1 m of accumulation per 5500 yr in a 100 km zone of deposition downwind, not including the bulk transport represented by the forward advance of dunes. Dune advance ranged from 23 m (2.9 m high dune) to 3 m (23 m high dune) during April‐October 1980. The study area consists of dune, interdune, sand sheet and siliciclastic sabkha terrains, each of which is characterized by differing drift rates, and differing rates of erosion or deposition. Sedimentation occurs by lateral movement of dunes and interdunes, and vertical accretion by sand sheets and sabkhas.

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Stokes surfaces in aeolian deposits are caused by wind scour of unconsolidated material to a roughly planar horizon controlled by near‐surface water‐tables (Stokes, 1968). A water‐table forms a downward limit of scour through the cohesion of damp or wet sand near water‐table, and through early cementation by evaporites precipitated in the sediments as water evaporates near the sand‐air interface. Study of modern analogues reveals that Stokes surfaces exist in a variety of depositional settings, including a coastal offshore prograding sand sea (Jafurah, Saudi Arabia); a coastal onshore prograding sand sea (Guerrero Negro, Mexico) and a continental sand sea (White Sands, New Mexico, USA). These modern analogues indicate that our concept of Stokes surfaces must be broadened to include the following: (i) modern analogues for Stokes surfaces described here cover areas on the order of 25 km2. These may be as representative of similar surfaces in ancient rocks as hypothesized plains of deflation requiring removal of entire sand seas; (ii) Stokes surfaces occupy a continuum in scale from local to extensive, and erosional surfaces of different magnitude may be stacked closely in the sediments; (iii) Stokes surfaces, although erosional in nature, are commonly associated with deposits both above and below the Stokes bounding surface which plainly reveal the influence of a near‐surface groundwater control on wind sedimentation. Moreover, the erosional relief of the bounding surface itself (as well as other features) reveals the influence of a groundwater‐table; (iv) Stokes surfaces may be diachronous, representing the lateral shift of a zone of scour within a sand sea rather than simultaneous removal of all dunes from the area encompassed by the erosional surface; (v) Stokes surfaces and associated deposits are often laterally transitional to surfaces and deposits of adjacent depositional environments, including interdunes, tidal flats, lagoons, beaches, lakes and non‐aeolian sabkhas. Finally, modern examples from different depositional settings suggest that while most Stokes surfaces have many features in common (such as erosional ridges due to early cementation), there are some features which may, with further study, be revealed to be distinctive of an individual depositional setting.

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The origins and sedimentary features of grainfall‐, avalanche‐, and ripple‐produced strata have been studied experimentally in a wind sedimentation tunnel. Rate of deposition, wind velocity and wind duration have been shown to control specific sedimentary features of these types of strata. Grainfall‐produced strata were deposited on a horizontal surface, and surfaces sloping up to the angle of initial yield for dry sand (about 34°). Thickness of a grainfall‐produced stratum depended upon rate of deposition and duration of a specific wind event. Grainfall‐produced strata were both non‐graded and graded. Graded strata were produced by changes in wind velocity which controlled size of sand in transport and flying distances of individual grains. Distinctive features of grainfall‐produced strata are: (a) gradual thinning, or tapering downwind (e.g. down the simulated slipface and across the simulated interdune; (b) extreme variability of thickness from less than 1 mm (wind gusts of a few seconds) to 10 cm or more (sustained gusts). Aeolian avalanche‐produced strata were formed when grainfall‐produced strata steepened above the angle of initial yield and sheared downslope. A rapid transition in sedimentary features from top to bottom of the slipface characterized avalanche‐produced strata of the slump degeneration type in dry sand derived from grainfall deposition. Fadeout laminae formed near the top of the simulated slipface and about 1 m farther down the slipface were flame structures and drag folds. Near the base of the slipface, the avalanche truncated and then overrode grainfall‐produced deposits. Distinctive features of avalanche‐produced strata for a 2.5 m long slipface are the deformation structures, a thickness of 1 or 2 cm, sandflow toes, and steep dip (34°). Each avalanche‐produced stratum was roughly tabular in cross‐section parallel to wind direction, with gradual pinchout upslope. Aeolian ripple‐produced strata were deposited on horizontal surfaces, and surfaces sloping to as much as 28°. Thickness of a ripple‐produced stratum depended upon rate of deposition, morphology of the ripple, and rate of ripple migration. A maximum thickness of several centimetres was observed for a single ripple‐produced stratum. Shape and attitude of ripple foresets was controlled by ripple morphology. Distinctive features of aeolian ripple‐produced strata are: (a) presence of ripple foresets; (b) abrupt changes in thickness of a stratum or pinchout over downwind distances of a few centimetres; (c) low average foreset‐to‐diastem angle (10–15°); (d) low ripple‐climb angle (<10°).