Vocabulary Terms
You should be able to define the following terms.
Thrust Sheets | Allocthonous | Autochthonous | allochthon |
autochthon | Window ("Fenster"" | Klippe | decollement |
basal shearing plane | "Thin-skinned" Tectonics | Nappe | Tectonic transport |
Ramp | Flat | Cutoff Angle | Cutoff-line |
foot wall ramp | lateral ramp | hanging-wall flat | branch point |
horses | duplex | imbricate fan | floor thrust |
roof thrust | normal duplex | antiformal duplex | forward-dipping duplex |
imbricate splay fault | Transfer zone | tear fault | compartmental faults |
Critical taper |
Concepts
You should be able to give short answers to the following questions:
1.) What is the significance of Thrust Faults in regional tectonics?
2.) What are the regional components of a thrust fault system (allocthon, autochthon, klippe, windows, basal decollement etc.).
3.) Draw a cross-section of an idealized thrust fault. Label the geometric components of the thrust fault (ramps, flats, cutoff angles, cutoff lines, forced-folds). Explain how this geometry develops (i.e., Where and why do flats and ramps form?)
4.) Draw a cross-section through an idealized duplex structure. Label the major components (Horses, floor thrust, roof, thrust). Explain how in-sequence, or out of sequence thrust faulting gives rise to duplexes
5.) What is an imbricate fan?
6.) What is the significance of pore-fluid pressure in the development of large thrust-sheets?
7.) Explain the significance of "critical taper" in the "wedge-model" of thrusting.
8.) Why do tear-faults develop? What is the significance of "transfer zones"?