Coalification in Carboniferous sediments from the Lötschberg base tunnel

Abstract

Vitrinite reflectance (Rr), proximate analysis and carbon isotope composition (δ13C) have been used to characterise coal samples from two zones of Late Carboniferous sediments (Gastern and Ferden) in the Aar massif where they are penetrated by the Lötschberg base tunnel (constructed between 1999 and 2005). Samples are characterised by variable ash yields (21.7-93.9%; dry basis); those with ash yields of less than ~50% and with volatile matter content (V;dry ash-free basis) within the limits 2