Welcome to SHED Earth. SHED refers to Schmidt hammer exposure dating: a technique that provides a cost-effective solution for dating the exposure of granite surfaces. This can be used to constrain the timing of past events, which permits a better understanding of the links between climate and landscape evolution.
The approach is based upon a study by Tomkins et al. (2016)1, in which a statistically significant relationship was observed between the exposure ages (derived from terrestrial cosmogenic nuclide dating), and Schmidt hammer rebound values (R-values) of 25 granitic surfaces from NW England and Scotland. This has recently been updated with 40 additional exposure ages from across Scotland and Ireland2. Calibration samples now span the last ~24 thousand years and encompass the entire post-Last Glacial Maximum (LGM) history of the British-Irish Ice Sheet. In addition, a new curve has recently been made available for the Pyrenees18, based on 54 TCN dated surfaces from across the mountain range. These new data appear consistent with previous research1 and indicate that this method can be applied successfully in contrasting climatic regimes.
While further work is required to test these calibration curves in a range of landscapes 21, this approach is cost- and time-efficient and is of comparable accuracy to ages derived from terrestrial cosmogenic nuclide dating23, making it useful for researchers and students alike. In turn, we hope that SHED will be of value to the Quaternary community, in that it can complement existing TCN studies in poorly dated regions and can be applied widely to undated glacial landforms.