Depth estimation using diameter-thickness ratios in larger benthic foraminifera

The diameter-thickness ratio (D/T) of larger benthic foraminifera varies indirectly with depth. Increased turbulence thickens the test, whilst decreased light intensity causes a flatter test. It is shown that in a nearshore-offshore transect the D/T gradient is similar between reefs, but stretched over a larger depth gradient. In facies analysis an increase in D/T can either be caused by decreased hydrodynamic energy, increased transparency or increased depth (or a combination of these).