Stratigraphy

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UNIVERSITY OF CHILE
Department of Geology

Stratigraphy
J.P. le Roux

With

acknowledgment and

to

numerous (J.M.

sources,

including:

Stratigraphic and

Principles

Practice

Weller,

1960);

Stratigraphy

Sedimentation (W.C. Krumbein & L.L. Sloss, 1963); A Guide to Stratigraphic Classification, Terminology and Procedure (H.D. Hedberg, ed., 1975); TheGeology of Stratigraphic Sequences (A.D. Miall, 1997), Terrigenous Clastic Depositional Systems (W.E. Galloway & D.K. Hobday, 1983), Physical Geology (N.K. Coch & A. Ludman, 1991), Sedimentology and Stratigraphy (G.Nichols, 1999) and references quoted therein.

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Index
A. Stratigraphic Principles
1. Introduction a. General concepts b. Definitions i) Strata ii) Stratigraphic units iii)Stratigraphy iv) Stratigraphic terminology v) Stratigraphic nomenclature vi) Stratotypes vii) Type locality viii) Type area 2. The Origin of Stratification a. Physical controls b. Chemical controls c. Biological controls 3. Working Hypotheses a. Superposition i) Shape of lithosomes ii) Sedimentary structures iii) Trace fossils iv) Tectonic structures b. Uniformitarianism c. Biologic succession e.Catastrophism f. Relative ages 4. Geologic Time a. Measurements of time i) Radiometric dating methods ii) Other dating methods b. Geologic time scale i) Eons

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ii) Eras iii) Periods iv) Epochs v) Ages vi) Chrons

B. Stratigraphic Information
1. Outcrops a. General field procedures i) Selection of outcrops ii) Equipment iii) General descriptions iv) Samples b. Measured profiles 2. Boreholes a.Lithologic logs i) Borehole core ii) Sidewall core iii) Chips b. Mechanical logs i) Caliper logs ii) Drill-time logs c. Geophysical logs i) Spontaneous logs ii) Induction logs d. Combined logs 3. Laboratory a. Binocular microscope b. Petrographic microscope c. Heavy mineral analysis d. Textural analysis e. Insoluble residue analysis f. Chemical analysis

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4. Geophysical Surveys a. Magneticsurveys b. Gravity surveys i) Reflection seismograph surveys ii) Refraction seismograph surveys c. Seismic surveys d. Radiometric surveys 5. Geochemical Surveys 6. Aerial Photography a. Introduction b. Qualitative photo-interpretation i) Climate ii) Landforms iii) Vegetation iv)Tone or color v) Drainage pattern c. Quantitative photo-interpretation 7. Remote Sensing a. Introduction b. Lithologicmapping i) Laboratory spectra ii) Field spectra iii) Selection of spectral bands 8. Representation of Stratigraphic Data a. Sections and cross-sections i) Columnar sections ii) Stratigraphic cross sections iii). Geologic cross-sections b. Stratigraphic maps i) Maps based on the external configuration of stratigraphic units ii) Maps based on the composition of stratigraphic units iii) Maps based on thetextural variation of stratigraphic units iv) Maps based on the biological variation of stratigraphic units

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v) Composite maps

C. Stratigraphic Relationships
1. Introduction 2. Definitions 3. Vertical relationships between lithosomes a. Conformable relationships b. Unconformable relationships i) Types of unconformities ii) Recognition of unconformities 4. Lateral relationships betweenlithosomes a. Pinchout boundaries b. Interfingering boundaries c. Laterally gradational boundaries 5. Combined vertical and lateral relationships a. Walther’s law b. Transgression and regression i) Coastal deposits ii) Sequence of environments iii) Age of lithosomes iv) Chronostratigraphic boundaries v) Depositional boundaries vi) Pinchout and erosion 6. Stratigraphic cycles a. Calendar-band cyclesb. Solar-band cycles c. Milankovitch cycles d. Megacycles e. Supercycles f. Supercontinent cycles

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D. Stratigraphic Classification and Analysis
1. Lithostratigraphy a. Introduction b. Definitions c. Types of lithostratigraphic units i) Formal lithostratigraphic units ii) Informal lithostratigraphic units d. Lithostratigraphic boundaries e. Lithostratigraphic correlation i) Lateral...