Nucleation of Stick-Slip Instability Within a Large-Scale Experimental Fault Effects of Stress Heterogeneities Due to Loading and Gouge Layer Compaction

Geodetic observations and large‐scale laboratory experiments show that seismic instability is preceded by slow slip within a finite nucleation zone. In laboratory experiments rupture nucleation is studied mostly using bare (rock) interfaces, whereas upper crustal faults are typically filled with gouge. To investigate effects of gouge on rupture...

The role of detrital anhydrite in diagenesis of aeolian sandstones (Upper Rotliegend, The Netherlands): Implications for reservoir-quality prediction

The Rotliegend (Upper Permian) reservoir interval in the Southern Permian Basin (SPB) contains low-permeability streaks corresponding to anhydrite-cemented intervals. An integrated study was conducted using core, cuttings, thin sections and well-log data from a gas exploration well and two geothermal wells that target the zone of interest. This...

Moisture and salt transport in three-layer plaster/substrate systems

We have investigated whether a plaster which has two plaster layers with different pore sizes can act as a salt accumulating plaster system, in which salt crystallizes in the base layer of the plaster and not in the substrate or at the external surface. We used two substrates; fired-clay brick and Bentheim sandstone. On the substrate we applied...

Black weathering of Bentheim and Obernkirchen sandstone

Black weathering of sandstone in monuments is widespread. Some obiects owe their name to it, like the Porta Nigra in Triet (Germany). Other than the black gypsum crusts common on limestone, the black weathering layer on sandstone is rather thin and well adhe¡ent. Formation of such layers on Bentheim and Obernkirchen sandstone, both widely used...