26 CHAPTER 6 SEDIMENTARY ROCKS IN THE DEPOSITIONAL ENVIRONMENT Secondary Sedimentary Structures Fossils - remains or traces of plant and animals and animal activities preserved in sedimentary rocks - mostly hard parts, molds, casts, prints, tracks - conditions for preservation: &#9;1) rapid burial &#9;2) possession of hard parts - trace fossils indications of ancient organism's life style - burrows, trails, etc. 27 CHAPTER 6 SEDIMENTARY ROCKS IN THE DEPOSITIONAL ENVIRONMENT Importance of sedimentary structures - paleoclimatic studies - paleocurrent studies - determines sediment transport medium - provide clues about depositional environments - aid in the interpretation of prehistoric life 28 CHAPTER 6 SEDIMENTARY ROCKS SEDIMENT TO SEDIMENTARY ROCKS Lithification - the processes by which unconsolidated sediments are converted to sedimentary rocks 1) Compaction 2) Cementation 3) Crystallization (Precipitation) and/or Recrystallization 29 CHAPTER 6 SEDIMENTARY ROCKS CLASSIFICATION OF SEDIMENTARY ROCKS Two Main Classes of Sedimentary Rocks 1.
(plant and animals and animal activities; preserved; L:in sedimentary rocks) (unconsolidated sediments; are converted; to sedimentary rocks)
plant and animals and animal activities unconsolidated sediments
preserved are converted
L:in sedimentary rocks
to sedimentary rocks