Understanding Subtrigonal Structures in Tectonically Active Regions

Subtrigonal refers to a type of geological structure that is characterized by a depression or basin that is formed by the erosion of a layer of rock that is softer than the rocks surrounding it. This type of structure is often found in areas where there has been significant tectonic activity, such as faulting or folding, and can be an important feature in understanding the geological history of a region.

In the context of your question, "subtrigonal" is likely being used to describe a specific type of geological structure that is present in the area where the faults are located. The presence of subtrigonal structures can provide valuable information about the tectonic forces that have shaped the region over time, and can help geologists to better understand the geological history of the area.