In this paper, we apply for the first time the moving-windows application of the Poisson's theorem to the synthetic gravity and magnetic data, followed by calculations of the correlations of the Bouguer gravity and aeromagnetic data of Western Anatolia. The correlation coefficient, slope and intercept parameters were generated from the internal correlations existing between the gravity and magnetic anomalies. Relative negative correlation values of positive gravity and negative magnetic anomalies were found on the Menderes Massif and in the southern part of the Marmara sea. Higher heat flow values were also obtained from these regions. The negative correlation values can be seen on a profile taken along the 28 E longitude and are sourced from a large graben system which has been generated as a result of lithospheric extension in Western Anatolia since the Early Miocene. The grabens were filled up by approximately 2000-m-thick sediments. The negative correlation coefficients and high heat flow values correspond to relative uplift of the asthenosphere in these regions.