Under what circumstances will the front of a glacier advance, retreat, or remain stationary?

What was the great rift valley formed by

Who developed the theory of plate tectonics?

Tides are caused by a differences in the gravitational force of the sun at different points on earth. differences in the gravitational force of the moon at different points on earth differences in earth’s gravitational field strength at different points on earth’s surfac fluctuations in the gravitational attraction between earth and the moon.