Accommodation: The space available for sediment to accumulate (Jervey, 1988). Accommodation is a composite of eustacy, subsidence, compaction, tectonism, and erosion.

Cycle: (5th order) The fundamental building block of carbonate stratigraphic analysis. Refers to the smallest set of genetically related facies deposited during a single base level rise/fall event. Comparable to parasequence. Can be mapped across multiple facies tracts, as distinguished from autocycles.

Cycle Set: Bundles of cycles that show a consistent stratigraphic trend, either progradational, aggradational, or retrogradational (transgressive). Comparable to parasequence set.

High-Frequency Sequence: A (4th order) High-Frequency Sequence (HFS) is bound at its top and base by unconformities or their correlative conformities, and composed of systems tracts defined by base-level fall (LST), base-level rise (TST), and base level fall (HST) successions.

Composite Sequence: (Depositional Sequence, 3rd order) is a relatively conformable succession of genetically related strata, bound at its top and base by unconformities or their correlative conformities, and often composed of multiple unconformity-bound High-Frequency Sequences (HFS).

Maximum Flooding Surface: Surface that marks the turn-around from landward-stepping to seaward stepping strata. Farther out on platform, the MFS coincides with the downlap surface (depending on the degree of condensation of clinoform toes).
Recognition of the MFS is important for separating TST and HST, which in turn is important for other stratigraphic analysis. But, on the platform top (where a very large percentage of carbonate reservoirs occur) this can be difficult to pin down precisely.

Sequence Boundary: The unconformity or correlative conformity that bounds a sequence. The sequence boundary is not always a major physical feature, nor is every exposure surface is a sequence boundary. The sequence boundary commonly (but not always) represents a significant change in stratal arrangements and therefore reservoir properties.

Systems Tracts: Lowstand, Transgressive, and Highstand Systems Tracts are recognized by delineation of retrogradational, aggradational, and progradational cycle sets and component facies.

Transgressive Systems Tracts:

Highstand Systems Tracts:

Lowstand Systems Tracts:

Depositional Topography: Topography formed as a result of sediments being dropped from a moving medium, e.g. coastal bars and barriers, kame terraces, or sand dunes.

Carbonate: [mineral] A mineral compound characterized by a fundamental anionic structure of CO₃^-2.
[sed] A sediment formed by the organic or inorganic precipitation from aqueous solution of carbonates of calcium, magnesium, or iron, e.g. limestone or dolomite.

Greenhouse system:

Autochthonous: Formed or produced in the place where now found. The term is widely applied, e.g. to a coal or peat that originated at the place where its constituent plants grew and decayed, to rocks that have not been displaced by overthrust faulting, or to brecchia at an explosion crater that remains in its original position, with only minor rotation or translation of the fragments.

Icehouse System:

Borehole Image Logs:

Biostratigraphy: Stratigraphy based on the paleontological aspects of rocks, or stratigraphy with paleontological methods; specif. the separation and differentiation of rock units on the basis of the description and study of the fossils they contain.

Chemostratigraphy:

Magnetostratigraphy: All parts of stratigraphy based on paleomagnetic signatures.

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