ABSTRACT: In this study, causes of surface deformations observed along the Sarıgöl fault zone have been investigated. Sarıgöl Town is located at the southeastern end of the Gediz Graben. The rocks exposed in the study area, from bottom to top, are metamorphic rocks of Menderes Massif, Plio-Pleistocene aged Asartepe formation and Holocene alluvium. The Asartepe formation is made up of weakly cemented clastic rocks and unconformably overlies the metamorphic rocks. The mapped faults divide the Sarıgöl area in to 3 different blocks. One of the fault passing throughout Sarıgöl municipality exhibits current deformational patterns on irrigational chanells, asphalt roads and cracks on the walls of several houses. The amount of vertical displacement of surface rupture along the fault is about 20-45 cm in the year of 2000. On the other hand, the amount of displacement measured on the same profile in 2010 is 1.00 – 1.25 m. In this study causes for the additional vertical displacements of 60 – 85 cm which occurred in ten years were investigated in detail. Sarıgöl fault is defined as “Listric normal growth fault” in this study. Soil beds in the hanging wall fault pocket are sloped towards the concave-up fault surface. In this pocket, an impermeable CH-type clay level at a depth of 9.0 - 11.5 m from the ground surface is located, and this level is overlaid by the silty and sandy soil beds. Surface water are accumulated in the area of triangular shape which is located on the clay level in front of the fault plane. It is estimated that sandy soils, which back-tilted toward listric fault, have been eroded from the open space of fault by the piping under the effect of water and back-tilting after the raining. Formation of the open space in the fault is explained by the rotational movement on the hanging wall of the fault. In addition, subsidence developed on the hanging wall of the fault due to the problem caused by decrease of the water level and drought in the years between 2000 and 2010 were computed. An extra load of 1.0 t/m2 per meter of the decreasing water level was formed and the normally consolidated soil layers were overconsolidated. Amount of vertical displacement on the surface ruptures along the Sarıgöl fault depending on both seismic activity in the region and overconsolidation was investigated in detail.