Sequence Stratigraphy and Geologic Time

Abstract The maturation of sequence stratigraphy and the development of a refined geological timescale have provided the basis for much more detailed stratigraphic reconstructions than were possible as little as a decade ago. Earlier studies showing that measured sedimentation rates vary inversely in proportion to the timescale over which they are measured may now be placed in a context that relates rates and timescales to actual geological processes. As little as 10% of elapsed time may be represented by a vertical succession at any one location. Sediment breaks account for the remainder, and constitute a much more significant component of stratigraphic processes than is generally assumed. Research methods that assume stratigraphic continuity must take this fact into account.