What does the presence of deep-sea trenches indicate about plate interactions?

The presence of deep-sea trenches is a strong indicator of plate convergence and subduction. These trenches form at areas where one tectonic plate is being forced under another, a process known as subduction. When two plates collide, the denser oceanic plate typically descends beneath the lighter continental or oceanic plate, creating a trench.

The geological activity associated with this process, such as earthquakes and volcanic activity, further signifies that these areas are dynamic and are shaped by the interactions of tectonic forces. The deep-sea trenches are some of the deepest parts of the ocean, and their formation is a direct result of these subduction processes taking place at convergent plate boundaries. This understanding is crucial in the study of tectonics, as it reveals how the earth's lithosphere is constantly being recycled and reformed through these interactions.