Science Olympiad Dynamic Planet Practice Test

How do synthetic and antithetic faults relate to major faults?

1. Both dip in the same direction

2. Both assist in the formation of new plate boundaries

3. They always occur simultaneously

4. They are always oriented vertically

The correct answer is: Both dip in the same direction

Synthetic and antithetic faults are types of normal and reverse faults that are closely associated with the mechanics of extensional and compressional tectonics. The key detail regarding why the chosen response is correct lies in the orientation of these faults in relation to a major fault, specifically in extensional settings. When a major fault experiences movement, the synthetic faults form on the same side of the main fault and dip in the same direction as it. This is because they accommodate the same stresses and create structures that help dissipate the tension in the crust. In contrast, antithetic faults form on the opposite side of the main fault and dip in the opposite direction. However, the important aspect is that both types are influenced by the same fundamental tectonic forces and are linked to the main fault zone. This relationship enhances the understanding of how geological structures form and behave. It demonstrates the complexity of fault systems, where multiple fault types can exist and interact under similar tectonic conditions. The other options don't accurately reflect the relationships or behaviors of these faults. For instance, synthetic and antithetic faults don't always occur simultaneously or create plate boundaries. Furthermore, they aren't always oriented vertically, as their dip can vary based on the stress state in the region.