fault spring

When an aquifer encounters a vertical fracture in the Earth’s crust, it sometimes emerges from the fault as a surface spring. Halted by an impermeable rock wall, the water is forced up along the fault to a place where it bubbles out onto the landscape as a fault spring. If the aquifer’s subterranean path takes it near hot, young rock, it emerges as a hot spring—Pilgrim Hot Springs on Alaska’s Seward Peninsula is a good example. Fan-palm oases in the Mojave and other deserts are typically associated with cool-water fault springs.

Eva Saulitis