Geo. 101 – 1st Edition Lecture 13 Outline of Last Lecture I. Sedimentary RocksII. Sedimentary StructuresIII. DiagenesisOutline of Current Lecture I. Sedimentary Rocks Environmenta. Clasticb. Commonc. Biochemicald. ChemicalCurrent LectureClastic Sedimentary Environment: Agents of Transport:- Wind:o Most selective agento Results in well sorted sedimentso Sand, Silt, or Dust (sand grains may be frosted)o EX: Very well sorted, Quartz Sandstone, Cross Bedding- Water:o Selection and sorting varyo Depends on strength of currento EX: Faster moving waves on a beach can move gravels, deeper water the grain size decreases.o Depositional Environments- Glacial Ice:o Least selectiveo Results in poorly sorted sediments Lack of bedding or other structures- Gravity:o Results in poorly sorted sediments – Angularo Think of like a rock slide: Rocks falling and tumbling to the ground Hitting the ground and breaking into pieces (various sizes)These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Common Sedimentary Environments:- Continental: (Clastic dominates)o Streams (fluvial) Rivers (channelized flow transports sediment)- Sand and Gravel fill concave-upward channels.o Desert (minor chemical)o Lakeo Glacial- Shoreline (Clastic/Chemical/Biochemical)o Deltaic (where rivers enter the ocean)o Tidal Flat (exposed at low tide)o Beach- Marine (Mostly Chemical and Biochemical)o Continental Shelfo Continental Margino Reefso Deep SeaBiochemical Sedimentary Environments: - Carbonate Deposition:o Marine Settingo Limestone and Dolostoneo Composed of Carbonate Minerals (Calcite, Aragonite) Property Effervescenceo Precipitated by organisms or inorganicallyo Reefs are mound shaped organic structures composed of carbonate skeletons of organismsChemical Sedimentary Environments:- Evaporite:o Salts form as water evaporates from a shallow basino Modern EX: Great Salt Lake, Death Valleyo Ancient EX: Mediterranean Sea, Dead
View Full Document
Unlocking...