Mohammad Hassan Asadiyan Falahieh - Emeritus member of Payam-e Noor University, Ahwaz/Iran

The goal of this paper is an attempt to understand geodynamics from study in geomorphology. All geomorphic evidences indicate Earth’s crust twisted from top and down spirally around two hinges: Aleutian and Scotia. Due to earth’s tilt, interaction of N-source and S-source produce mountainous spot (Himalaya) in the east and hollowware spot (Bermuda) in the west, this sources is originated from Mecca-spiral. M-spiral is mother source which after billion years of dahwing (rolling) and tahwing (spreading) lifted N/S-sources behind and itself settles in the current position. Westward drift of geomagnetic field could be due to this reason. Rotation differentiation between North Pole(NP) and South Pole(SP) beside Coriolis effect are main reasons for Spiral Tectonics(ST).Crust deformation developed within two periods, in the first period Red Sea and in the second period, Pacific Ocean formed due to inverse rolling of Earth’s wing named a/b and A/B: Red Sea from a/b-wing and Pacific Ocean from A/B-wing. Mecca as a Geodynamic Pole (GP) located in the central bar and Pacific in the peripheral. It seems in the center of the earth, spiraling spread in all direction so build spherical core and spherical mantel but toward the surface polarized in specific direction so produce semi harmonic fragmentation. Among these fragments, just Arabia, which located in the surface central bar, has cylinder structure. This dynamic accompanied by rifting occurred in the point where sense of spiral is changes these points have been named catastrophic zone (CZ), e.g. Aleutian Trench and Scotia Ridge. For example, Helical rolling of Eurasia around Africa caused N. America split from Eurasia and pulled in reverse direction, therefore produce Atlantic Ocean in between (like nude-null in physics).

Dahw, Tahw, Spiral, Sigmoid, Catastrophic Zone