How are pebbles formed on Mexican beaches?

Pebbles on Mexican beaches are gradually formed through natural geological and hydraulic processes. They typically undergo prolonged grinding and shaping by forces such as rivers, ocean waves, and wind. Below are key steps in the formation process:

1.  Rock Source: The raw material for pebbles usually originates from surrounding rock formations. Most pebbles originate from harder rocks like granite, limestone, or basalt.

2. Rock Fragmentation: These rocks begin breaking apart under natural forces such as earthquakes, weathering, or mountain formation processes. These fragments may eventually be carried to the ocean by rivers, streams, or other water bodies.

3. Water Action: The erosive power of seawater and wave impact carry rock fragments to beaches. Through repeated washing and pounding by waves, the stones gradually become smoother and rounder. This process can take millions of years.

4. Long-Term Abrasion: The salt content of seawater, wave impacts, and the drifting action of currents continuously grind these rocks. Harder rocks typically endure longer, while softer ones are worn down into smaller particles.

5. Final Pebble Form: Through prolonged grinding and shaping, these rock fragments become increasingly smooth and rounded, ultimately forming the pebbles we observe. Pebble color, size, and shape vary across different beaches, depending on local geological composition, rock types, and water current characteristics.

The types of pebbles found on Mexican beaches may correlate with the region's geological features. For instance, beaches along the Pacific coast may feature more basalt-derived pebbles, while those along the Caribbean coast may have more pebbles formed from limestone or coral fragments.