Changes

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

The basement fault block pattern in sedimentary basins was formed in multiple tectonic and metamorphic episodes during the Archean and Proterozoic Eons. Basement tends to control most of the local structure and much of the stratigraphy within the overlying, younger sedimentary section. It is along the shear zones, or block boundaries of the basement, that we generally find the faults or other structures in the overlying sedimentary section. These zones of weakness are periodically reactivated by tectonic stresses or gravitational loading. Consequently, they have influenced depositional patterns and locations of structures throughout geologic time.

The [[basement]] fault block pattern in sedimentary basins was formed in multiple tectonic and metamorphic episodes during the Archean and Proterozoic Eons. Basement tends to control most of the local structure and much of the stratigraphy within the overlying, younger sedimentary section. It is along the shear zones, or block boundaries of the basement, that we generally find the faults or other structures in the overlying sedimentary section. These zones of weakness are periodically reactivated by tectonic stresses or gravitational loading. Consequently, they have influenced depositional patterns and locations of structures throughout geologic time.

==Study of shield areas==

==Study of shield areas==

</gallery>

</gallery>

The Landsat and side-looking airborne radar(SLAR) images of exposed Precambrian crystalline crust ([[:file:using-magnetics-in-petroleum-exploration_fig14-4.png|Figure 1]]) show highly lineated terrains and demonstrate that the linears fall into multiple parallel or subparallel sets of varying strike directions. These overlapping [[fracture]] sets cut the basement into blocks of varying shapes and sizes. This collection of basement blocks is the '''basement fault block pattern'''.

The Landsat and side-looking airborne radar(SLAR) images of exposed Precambrian crystalline crust ([[:file:using-magnetics-in-petroleum-exploration_fig14-4.png|Figure 1]]) show highly lineated terrains and demonstrate that the lineations fall into multiple parallel or subparallel sets of varying [[strike]] directions. These overlapping [[fracture]] sets cut the basement into blocks of varying shapes and sizes. This collection of basement blocks is the '''basement fault block pattern'''.

==Precambrian surface topography==

==Precambrian surface topography==

The intensity of fracturing and mylonitization of the rocks in shear zones explains why these zones generally erode low and why they tend to control the topography of the Pre-Cambrian surface. This surface, in turn, controls much of the structure in the lower part of the sedimentary section through gravitational compaction of the sedimentary rocks.

The intensity of fracturing and [http://encyclopedia2.thefreedictionary.com/mylonitization mylonitization] of the rocks in shear zones explains why these zones generally erode preferentially and why they tend to control the topography of the Precambrian surface. This surface, in turn, controls much of the structure in the lower part of the sedimentary section through gravitational compaction of the sedimentary rocks.

==Canadian Shield example==

==Canadian Shield example==