Geology 103Sedimentology and Stratigraphy

Tim HornerGeology Department, CSU Sacramento

Lecture #8:

Mass movements, sediment gravity flows

Reading assignment:

Boggs, 5th ed., pp. 31-33, 38-41

SACRAMENTOSTATE

Types of mass-movements

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Table 2.1, p. 32

Features of a debris flow deposit:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.7, p. 37

Matrix strength supports grains in a debris flow:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.6, p. 33

Grain-to-grain interaction supports grains in a grain flow:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.6, p. 33

Features of a grain flow deposit:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.7, p. 37

Excess pore pressure supports grains in a liquified (fluidal) flow:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.6, p. 33

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.7, p. 42

Features of a liquified (fluidal) flow deposit:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.4.1, p. 34

Parts of a turbidity current:

Turbulence supports grains in a turbidity flow:

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.6, p. 33

From Boggs, Principles of Sedimentology and Stratigraphy, 5th ed., Figure 2.7, p. 37

Features of a turbidity flow deposit: