16: Cross Stratification
- Page ID
- 4252
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- 16.1: Stratification and Cross Stratification
- The term texture is commonly used in geology to apply to features of a sediment or a rock on the scale of individual particles, whereas the term structure is used for geometrical features on a scale much larger than particles. Stratification is one kind of sedimentary structure. A succinct way of defining stratification is layering by sediment deposition.
- 16.2: The Nature of Cross Stratification
- Cross stratification varies enormously in geometry. This is presumably a reflection of the great diversity of bed configurations produced by fluid flows over loose beds of sediment.
- 16.3: The Basic Idea Behind Climbing-Bed-Form Cross Stratification
- In general terms, the fundamental idea about cross stratification is easy to state: as bed forms of one kind or other pass a given point on the bed, both the bed elevation and the local bed slope change with time.
- 16.4: Important Kinds of Climbing-Bed-Form Cross Stratification
- This section presents the substance of what the major kinds of cross stratification in the sedimentary record look like. They conveniently fall into (1) unidirectional-flow cross stratification, on a small scale corresponding to ripples and on a larger scale corresponding to dunes, and (2) oscillatory-flow cross stratification. Unfortunately there is little I can say at present about combined-flow cross stratification.