Basic Principles in Tectonics

Carlos Cramez & Jean Letouzey

Contents:

1- Mechanical Principles
2- Tectonic General Concept
3- Attempt to Classify Tectonic Regimes
4- Volume Problem
    4.1- Scale Problems
    4.2- Volume Problems in Compressional Tectonic Regimes (σ₁ horizontal)
       4.2.1- Compression-------Shortening-------Uplift-----Erosion
       4.2.2- Balanced Structural Interpretation
       4.2.3- Depth to Detachment
       4.2.4- Limitations of Depth to Detachment Calculations
       4.2.5- Volume Conservation
       4.2.6- Kink Method
       4.2.7- Kink Software
       4.2.8- Fault Propagation
   4.2.9- Fault-bend Fold
       4.2.10- Kink Method in Seismic Sections
    4.3- Volume Problems in Extensional Regimes (σ₁vertical)
       4.3.1- Extension------Subsidence-----RSL Rise-----Sedimentation
       4.3.2- Detachment Surface
       4.3.3- Normal Faults & Volume Problems Seismic Lines are Time Profiles (2)
       4.3.4- Fault Curvature with Depth
       4.3.5- Fault Geometry
    4.3.6- Graphic Construction of Depth Fault
       4.3.7- Fault Terminology
      4.3.8- Development of Hanging-wall Syncline
       4.3.9- Fault Intersection on Maps and Seismic Sections
5- Tectonic Regimes in Sedimentary Basins
        5.1- Basement Involved
            5.1.1- Compression (σ₁ horizontal) Tectonically Enhanced & Cryptic Unconformities
                 5.1.1.1- Folds & Thrusts
                       A- Fold
                   B- Reverse Faults
                       C- Thrust Belts
                 5.1.1.2- Compressive Strike-Slip
           5.1.2- Extension (σ₁ vertical) Stratigraphic Completeness
                  Generalities
                         a) Sequence of geological events
                         b) Dip of beds and dip of faults
                         c) Angle between the fault plane and the vertical
                         d) Depth of a detachment surface
                         e) Amount of extension
                         f) Ends of a normal fault
                         g) Normal faulting deformation
                         h) Intermediated fault blocks
                         i) No planar faults
                       j) Deformations in no planar faults
                         k) Associated grabens
                 5.1.2.1- Positive Tectonic Stress σ_t> 0
                      a) Normal Faults - Grabens
                      b) Pull-apart Basins (Local stresses)
                 5.1.2.2- No Tectonic Stress (σ_t = 0)
                 5.1.2.3- Negative Tectonic Stress (σ_t< 0)
                         a) Rift-type basins & Grabens
                         b) Continental margins divergent
                         c) Differential subsidence
                         d) Differential uplift
                         e) Transfer basins
     5.2- Basement not Involved
           5.2.1- Evaporitic mobile substratum
                  5.2.1.1- Compressive décollement structures
                5.2.1.2- Extensive salt structures
                        5.2.1.2.a- Basic Principles in Salt Tectonics
                        5.2.1.2.b- Origin of a dome
                        5.2.1.2.c- Evolution of dome's flanks
                        5.2.1.2.d- Faults associated with domes
                               A) Stretch faults
                               B) Growth faults
                        5.2.1.2.e- Evolution domes and residual structures
                              (i) Structural changes in the salt
                                          A. Mature domes
                                          B. Bottom pinch-off
                                          C. Overhang
                             (ii) Structural changes in sediments
                                          a) Collapses
                                          b) Turtle structures
                                          c) Haggis structures
                                          d) Raft Tectonics
                      5.2.1.2.f- Review of salt dome growth
                                   A) Mounded Stage
                                   B) Dome Stage
                                   C) Post-dome Stage
                        5.2.1.2.g- Potential reservoirs and traps
                        5.2.1.2.h- Post-sedimentary halokinetic movements
          5.2.2- Shaly mobile substratum
                 A) Compressional structures
                 B) Extensional structures
                     B.1- Plasticity
                     B.2- Under-compaction
                     B.3- Fault displacement
                     B.4- Fault associated with shale tectonics
                     B.5- Growth fault displacements
                     B.6- Growth faults and traps
     5.3- Surface Phenomena
           5.3.1 - Landslide and Extrados Fractures
           5.3.2- Folds and Faults associated with Gravity

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Copyright © 2001 Ccramez, Switzerland
Last update: August 2014, May 2022