Orogeny which developed in continental detachment systems at converged plate margins. Orogeny An orogeny is an event that leads to both structural deformation and compositional differentiation of the Earth's lithosphere (crust and uppermost mantle) at convergent plate margins. An orogen or orogenic belt develops when a continental plate crumples and is pushed upwards to form one or more mountain ranges; this involves a series of geological processes collectively called orogenesis. Orogeny is the primary mechanism by which mountains are built on continents. The word "orogeny" comes from Ancient Greek (, , + , , ). Although it was used before him,
Petermann Orogeny the Cambrian. Sediments are a mixture of fluvial conglomerates, sandstones, and siltstones. Several pull-apart structural grabens formed at flexures in the orogenic belt, forming the Levenger and Moorilyanna Grabens. The Petermann Orogeny is dominated by south-over-north movement on several large, anastomosing curved thrust faults. The prime thrust fault is the Woodroffe Thrust, which is a laminated pseudotachlyte-schist zone up to 300 metres thick. This has accommodated up to 42 kilometres of vertical movement at an angle of about 15 to 20 degrees. The structure of the Petermann Orogen within the Musgrave Block is considered to be a "flower-structure", which is