More specifically, "ground conditions" is a term sometimes used to describe the amplitude, solidity, density, and many other variables of the rock during an earthquake.
More specifically, "ground conditions" is a term. This term is sometimes used to describe the amplitude during an earthquake. This term is sometimes used to describe solidity during an earthquake. This term is sometimes used to describe density during an earthquake. This term is sometimes used to describe many other variables of the rock during an earthquake.