GEOL 1001 Chapter : Ch6 Sed Rxs Part II
Document Summary
Classify sedimentary rocks: understand depositional settings (and associated sedimentary structures), identify aspects of earth"s history using information. Recorded in the sedimentary rock sedimentary record. Sand and rock fragments in a clay matrix. Mudstone (if it doesn"t break into platy sheets) Sedimentary structures: sedimentary structures = features imparted to sediments at or near deposition, layering, surface features on layers, arrangement of grains, important for deciphering conditions at or near time of deposition. Sedimentary structures: bedding reflects changing conditions during deposition (or erosion), changes can be , climate, water depth, current velocity, sediment source, disturbance by organisms. Sedimentary structures: water flowing over loose sediment creates bedforms, bedforms are linked to flow velocity and sediment size, e. g. , ripple marks, cross beds, dunes. Bedforms: ripples, cm-scale ridges and troughs, indicate flow (direction, strength, types, asymmetric ripples unidirectional flow, symmetric ripples wave oscillation, often preserved in sedimentary rocks.
