Previous studies about oceanic transform zones reveal major morphological and structural differences that cannot be explained by simple factors such as spreading rates or offsets. In order to determine how kinematic and mechanic parameters control the deformation pattern, we perform small-scale modeling using sand and silicone putty as analog material of brittle and ductile layers of oceanic lithosphere, respectively. The three dimensional depth geometry of these layers follows the thermal structure of the ridge-transform system. The structure of the deformed transform zone is very sensitive to input parameters, specially to the offset. The obliquity of the deformed zone with the extension direction (i.e., spreading direction in a natural system) depends on the offset and on the brittle layer thickness; for greater thickness or a shorter offset, the transform domain widens and the components of extension become significant. For smaller lithosphere thickness or larger offset, the transform domain becomes narrow with steeper walls and mainly undergoes strike-slip deformation. Such variability in possible controls on the offset length may help explain the structure complexity observed within the oceanic transform zones. A comparison with 28 natural systems indicates the same relationship of the offset with the angle between the principal transform displacement zone (PTDZ) and spreading direction. A relationship between offset and width is clearly established for Mid-Atlantic Ridge (MAR) transforms, as on analog models. A similar relationship is observed for the East Pacific Rise (EPR) transforms, but with greater variability. This difference is interpreted as resulting either from greater complexity of transform zones on EPR than on MAR making it difficult to estimate some parameters, from different mechanical behaviors between slow and fast spreading systems, or from higher rheological complexity of natural systems than our model. ¿ American Geophysical Union 1996