Geology 103 Sedimentology and Stratigraphy Tim Horner Geology Department, CSU Sacramento

SACRAMENTO STATE Geology 103Sedimentology and StratigraphyTim HornerGeology Department, CSU Sacramento Lecture #1: - Weathering and Sedimentary Textures Reading assignment: - Boggs, 5th ed., pp. 3 - 12, 45 - 63, 110 - 114

Sorting- visual and statistical values Figure 3.4 From Boggs 5th ed., p. 51

Roundness- visual estimates Figure 3.11 From Boggs 5th ed., p. 58

Roundness vs. sphericity Roundness the sharpness (or roundness) of the corners can be estimated visually or calculated Average Radius of Corners and Edges Roundness = _______________________________________ Radius of Maximum Inscribed Circle Sphericity how closely the object represents a sphere (3-d) determined by measuring x, y, z axis calculated with an equation:

Methods of measuring grain size Table 3.1 From Boggs 5th ed., p. 46

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 3.9, p. 57

Zingg Form diagram From Boggs (2006), Principles of Sedimentology and Stratigraphy, 5th ed., Fig. 3.10, p. 58

Surface texture From Boggs (2006), Principles of Sedimentology and Stratigraphy, 5th ed., Fig. 3.12, p. 60

Grain Fabric From Boggs (2006), Principles of Sedimentology and Stratigraphy, 5th ed., p. 61

Grain Fabric (imbrication) From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., p. 61 From Freidman and Sanders (1978), Principles of Sedimentology

Textural maturity Fig. 5.6 from Boggs (2006), Principles of Sedimentology and Stratigraphy, 5th ed., p. 111

Compositional maturity Table 1.2 from Boggs (2006), Principles of Sedimentology and Stratigraphy, 5th ed., p. 10

Compositional maturity Fig. 4.1 from Boggs (2nd ed.?) Principles of Sedimentology and Stratigraphy

Effect of grain size on composition From Blatt, Middleton and Murray, Origin of Sedimentary Rocks, 1980

Geology 103 Sedimentology and Stratigraphy Tim Horner Geology Department, CSU Sacramento