Contrast with strain . Bedrock, pebbles , and boulders may show striations produced when rocks trapped by ice were ground against bedrock or other rocks. Striations along bedrock surface are oriented in direction of ice flow across that surface. In minerals , parallel, threadlike lines, or narrow bands, on face of mineral. Reflect internal atomic arrangement.
Strike is always perpendicular to direction of dip.
Some coal mining is pursued in this manner. Course determined subsequent to uplift that brought more resistant beds within sphere of erosion. Also referred to as underground water and subterranean water . Also referred to as underground water and subsurface water . CaSO 4 2H 2 O. sulfide mineral - Mineral formed by direct union of element with sulfur.