A flame structure is a type of
soft-sediment deformation that forms in unconsolidated sediments. The weight of an overlying
bed
A bed is an item of furniture that is used as a place to sleep, rest, and relax.
Most modern beds consist of a soft, cushioned mattress on a bed frame. The mattress rests either on a solid base, often wood slats, or a sprung base. Many beds ...
forces an underlying bed to push up through the overlying bed, generally when both strata are saturated with water. The resulting pattern (in cross section) may resemble
flame
A flame (from Latin '' flamma'') is the visible, gaseous part of a fire. It is caused by a highly exothermic chemical reaction taking place in a thin zone. When flames are hot enough to have ionized gaseous components of sufficient density the ...
s. In order for the flame structure to occur, the overlying bed must be of a higher density than the underlying bed, or there must be differential pressures in the upper bed.
[Anketell, J. M. ''et al.'' (1970) "On the deformational structures in systems with reversed density gradients" ''Rocznik Polskiego Towarzystwa Geologicznego'' (''Annals of the Geological Society of Poland'') 40: pp. 3–30]
Basically prior to flaming these structures are unstable, under pressure,
and then subject to additional stress, such as being triggered by earthquakes.
[Brodzikowski, K., and Haluszczak, A. (1987) "Flame structures and associated deformations in Quaternary glaciolacustrine and glaciodeltaic deposits: Examples from central Poland" ''Geological Society of London, Special Publications'' 29(1): pp. 279–286] Earthquakes over
magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
6 can initiate flaming in large (hundreds to thousands of square kilometres) areas, but flaming can also be caused by as little as the repeated pounding of waves.
References
Sedimentary structures
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