Аннотация:This paper considers the results of experimental study of initiation and segmentation of the axial rift fissures in spreading ridges. The structure developing in transform and non-transform offsets are analyzed too. The experiments were carried out on colloidal matter composed from liquid and hard hydrocarbons. The conditions of similarity of processes in nature and experiment were fulfilled. The following modeling parameters were varied during the experiments: 1) thickness of the lithosphere in rift zones, non-transform or transform faults, 2) offset amplitude between spreading segments, 3) spreading rates and directions. The modeling shows that a developing of structures of different type in the MOR rift zones depends strongly on the lithosphere thickness in the rift axis, width of axial heating zone (attenuation lithosphere), spreading directionand to the less extent on its rate. The experiments allowed to determine the boundary amplitude of rift axis offsets after which the structure of rift zone changes from bending of ridge axis to formation of non-transform offsets and then to transform faults.