Reconstructing post-Jurassic overburden in central Europe: new insights from mudstone compaction and thermal history analyses of the Franconian Alb, SE Germany

Abstract. The Franconian Alb of SE Germany is characterized by large-scale exposures Jurassic shallow marine limestones and dolostones, which are frequently considered to be outcrop analogues for deep geothermal reservoir rocks in the North Alpine Foreland Basin farther south. However, burial history strata not well known as they were affected emersion, leading extensive erosion karstification with only remnants original Cretaceous Cenozoic cover preserved. To estimate thicknesses post-Jurassic overburden we investigated petrophysical properties thermal Lower Middle mudstones constrain their area. We measured mudstone porosities, densities, maturities organic material collected interval velocities from seismic refraction logging data mudstone-rich strata. Mudstone porosities P-wave vertical bedding then related a normal compaction trend that was calibrated on stratigraphic equivalent units Basin. Our results suggest maximum depths 900–1700 m, 300–1100 m attributed younger sedimentary overlying units. Compared previous considerations this implies more widespread distribution increased up ∼900 ∼200 Germany. Maximum critical understand mechanical diagenetical dolostones Upper Alb. study therefore help better correlate conditions below Here, can found at 5000 m.