Holostratigraphy

Holostratigraphy is a holistic approach to stratigraphy – it brings together every possible method to produce an integrated correlation that may have a much higher resolution than any one method alone can provide.  This approach is standard in many areas of Quaternary stratigraphical investigations, where it is more usually referred to as high-resolution stratigraphy.

In practice, successful holostratigraphy requires a team approach to focus on a particular problem, such as the subdivision and correlation of key sequences or the definition of a chronostratigraphical boundary.  For a single stratigraphical section one may, for example, calibrate against a detailed lithological log several different biostratigraphical schemes from different taxonomic groups, together with isotope curves (if applicable), interpreted Milankovitch cycles, and a magnetostratigraphical record.  This may provide an intermeshed sequence of ‘events’ at very closely-spaced intervals.  Such an approach is very important when system or stage boundaries are being formally defined by the various IUGS stratigraphical subcommissions, as it may highlight several key events, both biological and non-biological, that individually may not be globally distributed but taken collectively provide a boundary that can be recognised worldwide.

The terms high resolution and ultra-high resolution stratigraphy are sometimes used as alternative names to holostratigraphy, but both have been used generally in more restricted ways  – in particular to embrace what is here described as cyclostratigraphy, or to refer to a particularly detailed approach to integrated biostratigraphy.  Indeed, they have also been misused to imply a higher degree of correlation than has really been achieved.  The lack of precision makes them redundant as formal terms.

*This guide is based on that produced by Rawson et al. (2002) for the Stratigraphy Commission of the Geological Society of London.