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I. Tectonic Settings
A. Cratons
1. Continental shield
2. Continental platform
B. Orogenic Belts
C. Depositional basins
II. Environments of Deposition
A. Continental: streams deposits, alluvial fans, lake deposits, glacial deposits, wind deposits
B. Transitional: deltas, barrier islands, lagoons, tidal flats, estuaries
C. Marine: shallow marine (continental shelf), continental slope and rise (turbidity deposits), deep marine realm
III. Color in Sedimentary Rocks
A. Black and Dark Gray (especially shales): organic carbon and iron sulfides
B. Red and Brown (especially clastic rocks): iron oxides (hematite)
IV. Textural Interpretation
A. Textural Components: clasts, matrix, and cement
B. Main Observations: grain size, sorting, shape (roundness and sphericity)
C. Orientation of Grains

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V. Interpretation of Sedimentary Structures
A. Stratification (layering)
B. Internal Structures (graded bedding, cross-bedding)
C. Between-bed Structures (mud cracks, ripples, scour and sole marks)
D. Geopetal (sedimentary ‘way-up’) Structures
VI. Interpretation of Sand and Sandstone Types
A. Quartz-rich (mature; quartz sand)
B. Feldspar-rich (immature; arkosic sand)
C. Rock Fragment-rich (immature; lithic sand)
D. Clay-rich (immature; graywacke)
VII. Interpretation of Carbonates
A. Main Processes
1. Chemical direct precipitates (carbonate mud)
2. Biochemical: organic contribution (shells, etc.)
B. Main Components: mud, shells, oöids, rip-up clasts
VIII. Sedimentary Rock Record
A. Rock (lithostratigraphic) Units: named for geographic site
1. Formation
2. Group
3. Member
B. Time-rock (chronostratigraphic) Units
C. Facies Concept
1. Biofacies
2. Lithofacies
D. Sea-level Change
1. Transgression (onlap)
2. Regression (offlap)
3. Facies shift (Walther's Law)

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E. Correlation: determining equivalence between strata, an important component in the branch of geology called stratigraphy
1. Physical (lithostratigraphic)
2. Fossil (biostratigraphic)
3. Temporal (chronostratigraphic)
F. Unconformities: breaks in the stratigraphic record
1. Angular unconformity
2. Disconformity
3. Nonconformity
IX. Depicting the Past
A. Graphics for Correlation
1. Geologic column (local section) and columnar sections
2. Stratigraphic cross-sections (several local sections)
3. Structural cross-sections
B. Mapping Graphics
1. Geologic map
2. Paleogeographic map
3. Isopach map
4. Lithofacies map
1. (a) Shallow-marine deposits are indicated typically by mature sandstones and dark shales containing shallow-marine fossils. b) Deep-marine (including continental-rise) deposits are indicated typically by dark shaley sandstones and dark shales containing deep-marine trace and body fossils. c) Transitional (deltaic) environments are indicated typically by immature sandstones and shales containing mixed shallow-marine and freshwater fossils. d)
Continental (desert) environments are indicated typically by well-sorted sandstones and arkoses that are red and contain no fossils except continental terrestrial trace fossils.
2. Oxidation in the desert realm causes any iron to produce redness and any original organic material to be removed.
3. Matrix is fine inter-granular material deposited with the coarser grains at deposition or shortly thereafter. Cement is inter-granular crystalline void fill formed long after deposition (in most instances). Common cements in sandstones are: quartz; calcite; and hematite. Quartz is the most durable (hardest and most stable) cement.

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4. The immature nature of a poorly-sorted sandstone with mud matrix and angular grains suggests an unstable, tectonically active source where material is being shed rapidly into a terrestrial or marine basin. The mature nature of a quartz sandstone with well-sorted grains suggests a stable area. Fossil clams (marine organisms) and ripple-marks (shallow-water features) indicate a shallow-marine setting.
5. Textural differences between mature and immature are indicated below.
Mature well-sorted quartz-rich low matrix stable minerals rounded
Immature poorly sorted quartz-poor high matrix unstable minerals angular
6. The sequence of layers, limestone-shale-sandstone, suggests an increase in bottom energy and increasing proximity to clastic source, both indicative of progressive shallowing of water.
7. The Bahama Banks carbonate platform is highly productive today due to warm, clear, shallow
(less than 200 m) sea water that is saturated with calcium carbonate.
8. Features useful for determining the direction of current of the depositing medium (i.e., water and air) are: planar cross-bedding, trough cross-bedding, and asymmetrical ripples.
9. Gradual and continuous subsidence of a sedimentary basin allows great thicknesses of sedimentary rock to be deposited in shallow water. The subsidence rate was about equal to rate of deposition on average.
10. c
11. b
12. Mud cracks mean that the sediment was exposed to drying conditions at the surface. Graded bedding means that sediments of different sizes settled according to size after they entered standing water. Cross-bedding means that sediments were moved along by air or water and deposited on the front of a sand dune. Asymmetrical ripple marks mean that sediment moved by currents that were moving in one main direction.
13. Angular unconformities show truncation of inclined beds below the unconformity surface.
Disconformities show little or no truncation between essentially parallel beds.
Nonconformities show erosional effects on rocks that are not sedimentary (igneous and/or metamorphic rocks), but sedimentary layers overlie the nonconformity. Angular unconformities and disconformities demonstrate the effects of erosion on pre-existing sedimentary rocks. Nonconformities show effects of erosion on non-sedimentary rocks.
Angular unconformities develop after the older layers are tilted, whereas disconformities do not.
14. An isopach map shows the distribution of rock thickness, whereas a lithofacies shows the distribution of specific types of sedimentary rock.

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Student activities for in-depth learning:
1. Find some images of sedimentary structures on the web at one of many sites that show such illustrations, for example,
http://www.indiana.edu/~geol105/images/gaia_chapter_5/sedimentary_structures.htm. Make a sketch of two sedimentary structures of your choosing and briefly explain how they form and what they mean when found in sedimentary rocks.
2. Go to the Earth Science World Image Bank ( http://www.earthscienceworld.org/images/search/ index.html) and enter the keyword “unconformity.” Study the images of angular unconformities in particular. Pick out one and make a sketch of the main features that you see (sedimentary beds, the unconformity surface, etc.). Describe the order of events in the formation of this angular unconformity as shown in the photograph. Make a note of where the photograph was taken, the age of the rocks, and any other pertinent information.