Sequence stratigraphy

Sequence stratigraphy organizes sedimentary rocks into genetically related packages bounded by surfaces that record changes in accommodation and sediment supply.

Accommodation (geology): The space available for sediment to accumulate, controlled mainly by water depth and subsidence. Changes in available space relative to sediment supply govern stacking patterns and sequence boundaries.
Sequence boundary: A surface marking a break in deposition, commonly associated with subaerial exposure and erosion during relative sea-level fall. It commonly defines the base of a depositional sequence.
Seismic stratigraphy: The interpretation of sedimentary basin architecture from seismic reflection patterns and their bounding surfaces. Sequence stratigraphy grew from methods for recognizing depositional packages in seismic data.
Well log: A continuous downhole measurement of physical properties in a borehole. Log patterns help correlate sequence surfaces and interpret stacking where core is sparse.
Depositional sequence: A genetically related succession of strata bounded by unconformities and their correlative conformities. It is a particular sequence definition, commonly tied to subaerial unconformities.
Sediment supply: The rate and volume at which sediment enters a depositional basin. Its balance with accommodation helps determine whether shorelines advance or retreat.
Maximum flooding surface: A surface formed near the time of greatest marine transgression, commonly separating retrogradational from progradational strata. It marks a key turnaround in stacking patterns within many sequences.
Peter Vail: An American geologist associated with developing seismic stratigraphy and global sequence charts. His work helped establish sequence-based interpretations of seismic reflection records.
Seismic reflection: A geophysical method that images subsurface layers by recording reflected sound waves. Reflection geometries reveal basin-scale packages and their bounding surfaces.
Genetic stratigraphic sequence: A succession bounded by maximum flooding surfaces and interpreted as a genetically related depositional unit. Its bounding surfaces differ from those used in depositional-sequence models.

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