Quantification of physical and chemical paleoweathering at the microscale: a new concept

Abstract Weathering is a basic geological process that refers to the breaking down or dissolving of rocks and minerals on surface earth. However, weathering characteristics may vary among different lithologies even under similar conditions. To evaluate quantitatively compare physical chemical index alteration types rock, new concepts paleo-weathering such as absolute degree relative are proposed for microscale studies. For quantification weathering, (IPW) introduced. The defined ratio between area fractures formed during stages total thin section polarizing microscope it corrected by corresponding rock strength. intensity minerals, following two introduced: mass (TWM) ability (CWA). While TWM an integral function rate time CWA sum each mineral in within certain period. As case study, this concept applied weathered crystalline basement below post-Variscan nonconformity southwestern Germany. petrography geochemistry three drillings penetrating were investigated microscopy, X-ray diffractometry (XRD), scanning electron (SEM), fluorescence (XRF) inductively coupled plasma-mass spectrometry (ICP-MS). investigations illustrate how better extract quantitative information both, weathering.