There isn't one single scientific word that perfectly describes the movement of rocks and pebbles. The specific term depends on the process causing the movement:

* Erosion: This is the general term for the process of wearing away and transporting rock and soil by natural forces.

* Weathering: This refers to the breakdown of rocks into smaller pieces, but not necessarily their movement.

* Transportation: This broadly describes the movement of rocks and pebbles from one location to another.

* Sedimentation: This describes the process of rocks and pebbles settling and accumulating in a new location.

* Abrasion: This refers to the grinding and wearing away of rocks by friction, often caused by other rocks or sand.

* Fluvial processes: This refers to the movement of rocks and pebbles by flowing water, such as rivers.

* Glacial processes: This refers to the movement of rocks and pebbles by glaciers.

* Aeolian processes: This refers to the movement of rocks and pebbles by wind.

So, the most appropriate scientific word depends on the specific context of the movement. For example, you might say:

* "Fluvial erosion caused the movement of the rocks downstream."

* "Glacial transportation deposited these large boulders in the valley."

* "Wind abrasion smoothed the surface of the pebbles."