Fracturing and Porosity Channeling in Fluid Overpressure Zones in the Shallow Earth’s Crust

Figure 1

Examples of veins that may represent high fluid pressures in rocks. (a) Veins containing layer-parallel and perpendicular branches (Sestri Liguria, Italy). (b) Layer-parallel “beef”-type veins (Sestri Liguria, Italy). (c) Large vein with brecciated host rock (Isle of Kerrera, Scotland, UK). (d) Tree-like branching vein (Isle of Kerrera, Scotland, UK).

(a)

(b)

(c)

(d)