This paper is dedicated to the identification of parameters of soil stratums and earthen dams from accelerometer records by inverse analysis using three kinds of optimization algorithms. The first one is the Levenberg-Marquart (L-M) gradient-based method, the second one is based on a genetic algorithm (G-A) optimization process, and the third one combines the two search algorithms to complete the identification task more efficiently. The efficiency of the two first algorithms is studied by identifying the unknown parameters of a multilayer soil profile. Then, the global - local hybrid scheme is applied to identify the soil profile characteristics and determine some information gaps using experimental data recorded within the Adapazari city during the Kocaeli earthquake of August 17, 1999. Finally, the applicability of the proposed identification procedure is verified through comparison of the parameter identification results and experimental ones at Bradbury dam by using ground motions records during the 1978 Santa Barbara earthquake (in USA).