PALINSPASTIC CONSTRUCTION

Balanced Cross Sections

A cross section with internally consistent geometry: Concepts of balancing cross sections applies to all kinds of faulting and deformation, but was first developed in thrust systems.

Requirements:

• Balance occurs when bed lengths and cross-sectional area are equal in both deformed and undeformed state (except with volume loss due to consolidation and dissolution

• Structures drawn on section should be those observed in outcrop or limited to geologic structures expected in a particular environment.
• Cross section must be able to be restored to undeformed state. That is, removal of deformation should result in group of undeformed sedimentary rocks with expectable geometry

Approaches

• Line-length and area balancing
• Depth to detachment calculation--an outcome of area balancing

Value

• Fault displacement established
• Section may be correct

If it doesn't balance it can't be right. If it balances the cross section a possibly correct, acceptable solution.