Surface and sub-surface Schmidt hammer rebound value variation for a granite outcrop
Article first published online: 22 JUN 2010
Copyright © 2010 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 36, Issue 2, pages 170–179, February 2011
How to Cite
Černá, B. and Engel, Z. (2011), Surface and sub-surface Schmidt hammer rebound value variation for a granite outcrop. Earth Surf. Process. Landforms, 36: 170–179. doi: 10.1002/esp.2029
- Issue published online: 24 JAN 2011
- Article first published online: 22 JUN 2010
- Manuscript Accepted: 17 MAR 2010
- Manuscript Revised: 3 MAR 2010
- Manuscript Received: 7 DEC 2009
- Schmidt hammer;
- hory Mountains
This study presents rock strength variations at granite outcrops and in subsurface vertical profiles in the Jizerské hory Mountains, Czech Republic. Schmidt hammer rebound values in subsurface profiles change gradually from the bedrock surface downward. An exponential relation has been observed between the R-values and depth in rock outcrops to a depth of around 4·5 m. The exponential nature of the curve indicates that rock hardness increases more rapidly with depth in the uppermost 1?m section of the rock profile. A detailed study of rebound values obtained from both intact and polished rock exposures reveal effects of surface grinding on results of the Schmidt hammer method. The range of data collected increases after grinding, allowing more precise discrimination of rock surfaces in respect of age and weathering. The Schmidt hammer method may be used effectively as a relative-age dating tool for rock surfaces that originated during the Late Pleistocene. It is concluded that this time limitation can be significantly mitigated by surface grinding before measurement. Copyright © 2010 John Wiley & Sons, Ltd.