Depth control of intrastratal solution of heavy minerals from the Palaeocene of the North Sea

Several detrital heavy mineral species from Palaeocene sandstones of the central North Sea basin show surface features attributable to chemical etching. Garnet, staurolite, and kyanite, selected for study because of their basinwide distribution, show an increase in intensity of these etch features with depth, with staurolite and kyanite grains becoming skeletal. The latter two minerals also show a parallel decrease in abundance with depth, ultimately disappearing from the assemblage, staurolite around 8500' (2590 m) and kyanite around 7000' (2135 m). This trend is interpreted as being the result of increasing intrastratal solution with depth.