Fault arrays & rifting and sediment distribution Flashcards
Segment
Accounts for a part of a NF wich was originally interpreted as a single fault plane
(Scale is important and can change just how many segments you might see)
Relay ramp
A place with two faults with a ramp connecting them. The footwall of one fault is a hanging wall of another, creating a relay ramp. They can be soft-linked or hard-linked depending on the maturity of the faulting.
Dip direction of a ramp?
A ramp’s dip direction depends on the faults’ original orientation.
X-D diagrams
Diagrams where displacement (y) is put versus length (x). Usually creating a form of curve, if it’s not symmetrical
there is most likely another fault interaction. If there is a drop, it indicates ductile deformation of the fault
Branch lines
lines where two faults surface cut each other and connect
OBS: Branch lines can be parallel to the seismic view, and can therefore not always be seen
Conjugate faults
A cross-cutting set of fault planes which ideally intersect at angles of 60° and 120°, and have both left-handed and right-handed shear senses. The line of intersection is parallel to the direction of intermediate principal stress (σ 2).
It creates two NF’s and a dip in the middle in the shape of a triagle
Relative sea-level
Controlled by faulting, and changes are Relative in time and Space!
Onlap
Base-discordant: At first horizontal strata terminate against an inclined surface, or initially inclined strata terminate progressively up-dip against a surface of greater initial inclination
The surface rotates sediments filling in from the bottom of the basin. no tectites.
Tectonic history
Very important for location of potential reservoirs
What controls sediment distribution?
Faults
What is important in creating local accommodation space?
Fault interaction and linkage
