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C. Markers of continental fragmentation and oceanic opening Intro: Wilson orogenic cycles: tectoglob3d 1) Markers of extension and formation of an ocean GéoMapApp 73. Passive margins bordering an ocean bear marks of distension (normal faults and tilted blocks) which testify to the initial fragmentation before oceanic accretion. 2) Continental rifts: before the ocean, continental opening Google earth (Afars) + tectoglob3D 74. The initial stages of continental fragmentation correspond to continental rifts. Conclusion of II: 75. The dynamics of the lithosphere thus determine different paleogeographic periods, with periods of reunion of continental blocks, linked to orogenic collisions, and periods of fragmentation leading to the establishment of new ridges.