Question

The earth crust is unsta le explain two effect on the eath surface

Answer 1

since earth's crust is unstable earth quakes often occur on land because unstable crust allows flow of earthquake waves
since earth's crust is unstable formation of new landforms occurs

Answer 2

Due to increase of temperature in layers of earth the earth surface gets heated and cause damage of layers of earth and this leads to disastets and tsunami. So,these are two effects of earth's crust.