In this work, a high-resolution Atomic Force Acoustic Microscopy imaging technique is shown in order to obtain the local indentation modulus at nanoscale using a model which gives a quantitative relationship between a set of contact resonance frequencies and indentation modulus through a white-noise excitation. This technique is based on white-noise excitation for system identification due to non-linearities in the tip-sample interaction. During a conventional scanning, a Fast Fourier Transform is applied to the deflection signal which comes from the photo-diodes of the Atomic Force Microscopy (AFM) for each pixel, while the tip-sample interaction is excited by a white-noise signal. This approach allows the measurement of several vibrational modes in a single step with high frequency resolution, less computational data and at a faster speed than other similar techniques. This technique is referred to as Stochastic Atomic Force Acoustic Microscopy (S-AFAM), where the frequency shifts with respect to free resonance frequencies for an AFM cantilever can be used to determine the mechanical properties of a material. S-AFAM is implemented and compared to a conventional technique (Resonance Tracking-Atomic Force Microscopy, RT-AFAM), where a graphite film over a glass substrate sample is analyzed. S-AFAM can be implemented in any AFM system due to its reduced instrumentation compared to conventional techniques.