Question

In what type of plate boundary did subduction occur?

In what type of plate boundary did new crust form?

In what type of plate boundary did mountains form?

In what type of plate boundary did volcanoes form?

In what type of plate boundary did a river change its path?

Answer 1

- Subduction occurred at a convergent plate boundary (where one plate sinks beneath another — e.g., oceanic‑continental or oceanic‑oceanic subduction like the Nazca plate under South America).
- New crust formed at a divergent plate boundary (seafloor spreading at mid‑ocean ridges or continental rifts, e.g., the Mid‑Atlantic Ridge).
- Mountains formed at a convergent plate boundary (especially continent–continent collisions, e.g., the Himalaya from India‑Eurasia collision).
- Volcanoes formed mainly at convergent boundaries (subduction‑related arcs) and also at divergent boundaries (mid‑ocean ridges); some volcanoes are from intraplate hotspots (e.g., Hawaii).
- A river changed its path most often because of strike‑slip (transform) movement that laterally offsets channels (e.g., rivers offset by the San Andreas system); large uplift or subsidence from convergent or extensional tectonics can also reroute rivers.