The hyporheic exchange (HE) is defined as the interaction between stream water and groundwater, where the stream water passes back and forth between the active channel and subsurface flow paths (Runkel, 1998). The zone of this exchange is characterized by saturated pore spaces, under sand or gravel stream beds (Hancock, 2002) and near the adjacent banks of the stream (Ryan, 2010), that contain ...

Lubell proved this by observing that the left-hand side is a probability: it is simply the probability that a maximal chain, chosen uniformly at random, intersects A. The LYM inequality implies that an antichain in P([n]) has size at most ( n bn/2c ) , the size of the ‘middle layer’ in P([n]). (This can also be proved by partitioning P([n]) into ( n bn/2c ) disjoint chains.) Bollobás’ Inequalit...

An open question for solid-earth scientists is the amount of water in Earth's interior. The uppermost mantle and lower mantle contain little water because their dominant minerals, olivine and bridgmanite, have limited water storage capacity. In contrast, the mantle transition zone (MTZ) at a depth of 410 to 660 km is considered to be a potential water reservoir because its dominant minerals, wa...

[1] The one-dimensional model of Rudnicki and Chen [1988] for a slip-weakening dilating fault is extended to include shear heating. Because inertia is not included, instability (a seismic event) corresponds to an unbounded slip rate. Shear heating tends to increase pore pressure and decrease the effective compressive stress and the resistance to slip and consequently tends to promote instabilit...

The unsaturated zone (UZ) retains aqueous solutions against gravity by capillary forces. This suction state corresponds to a decreasing internal pressure of the water, which modifies its thermodynamic properties. Accordingly, the speciation of solutes and the solubility of solids and gases in such capillary solutions change. The volumetric capillary water content of the soil at high suction can...

Triaxial experiments show that samples of fault gouge deform distinctly differently than those from the adjacent fault damage zone (e.g., Chester and Logan, 1986). Rock samples in the damage zone follow a characteristic elastic-brittle behavior, whereas fault gouge readily compacts and deforms in a more ductile manner. In order to explain the apparent weakness of large plate bounding faults suc...