Suppose your object is a rod of steel, keeping its axis perpendicular to the ground during the fall.

After the impact, during a brief period of time, its length shortens due to the compressive force. This force = EAε, E = 2,06 x 10¹¹ N/m² is the modulus of elasticity of the steel, A the cross area of the rod and ε the elastic strain.

This force starts from zero until reaches a maximum when the rod speed is zero. The work done is ∫EAεdx = ∫EAεLdε, where L is the length of the rod. W = EALε² / 2.

For a steel object of 100kg, the volume is 100 / 7850 = 0.01274 m³. If the ground is hard enough, like a big hardened anvil, the kinetic energy transforms to an elastic energy of 1000J = 2,06 x 10¹¹ x 0.01274 x ε² / 2 => ε = 0,000873. The tension σ = Eε = 179830724 N/m² = 18,3kg/mm², what is below the yield point for a normal carbon steel, so the elastic assumption is OK.

In order to know how much (mm) the rod would deform, it depends on its length. For a length of 1m for example, it would shrank by 1000 x 0,000873 = 0.8mm. In this case, the force = σA = 179830724 x 0.01274 = 2289828 N or 233 tons.