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ZusammenfassungNach herk6mmlichen plattentektonischen Vorstellungen soll eine inaktive Subduktionszone am nordwesflichen Kontinentalrand von Sabah liegen. Reflexionsseismische Mei~da-ten der BGR zeigen jedoch, daf~ hier autochthone kontinentale Kruste mit einer oligoz~inen-friihmioz~inen Karbonatplattform progressiv yon einem allochthonen Gesteinsverband ikberschoben wird. Fortschreitender Zusammenschub seit dem frfihen Mioz~in fiihrte zur Anlage yon vier Deformationszonen: Tekonische Schuppen (Zone III); zwei iibereinander geschobene Verschuppungssysteme (Zone IV); G~irtel mit mehrphasiger Deformation (Zone V) und Durchspief~ungsstrukturen (Zone VI). AbstractWidely accepted plate tectonic models suggest that an inactive subduction zone lies along the north-west continental margin of Sabah. In contrast, interpretation of reflection seismic data acquired by BGR shows an autochthonous continental terrane comprising an Oligocene to Early Miocene carbonate platform being progressively overthrust by an allochthonous rock complex. Progressive compression resulted in the development of four structural zones: Imbrica'ced thrust sheets (Zone III); two thrust sheet systems one on top of the other (Zone IV); a complex zone with multiphase deformation (Zone V); and piercement ridges (Zone VI). R6sum6Les modules g6odynamiques que l'on admet habituellement comportem une zone de subduction inactive le long de la marge continentale nord-occidentaIe de Sabah. Toutefois, des mesures de sismique-r6flexion ex6cut6es par le BGR font apparakre qu'~ cet endroit, une cro~lte continentale autochtone, comportant une plateforme carbonat6e oligoe~ne 6omioc~ne, est chevauch6e progressivement par un complexe allochtone. La compression, qui s'est manifest& progressivement depuis le Miocene inf6rieur, a engendr~ quatre zones structurales: un ensemble d'6cailles tectoniques (zone III); deux syst~mes de lames tectoniques charri6s l'un sur l'autre (zone IV); une zone complexe ~ d6formation rrmltiphas& (zone V); des structures d'extrusion tectonique (zone VI). Karl ~emyr (3oHa 3), ~Ba aa~lBnra qemyfi~aTl, tx C~CTeM apyr Ha ~pyra (3oHa 4) norc c inoro~a3oBofi ~eqbopia-~Hefi (3OHa 5) H ~iamq3om,ie cTpyKTypl, I (3oHa 6).

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For the South Atlantic Ocean, the rifting period began during the Oxfordian-Kimmeridgian and ended progressively from the Hauterivian near the Agulhas Plateau to the early Albian in the vicinity of the Niger Delta. The Walvis Ridge/Rio Grande Rise system acted as a dam to marine incursions into the Angolan and Brazilian basins until the midAptian. The Parana Basin and the Torres syncline (Brazil), the Eastern Walvis Ridge and the Kaokoveld region (Namibia) form an originally continuous volcanic terrane created in the continental domain during the Late Jurassic-Early Cretaceous by tensional processes. This terrane corresponds to a failed rift arm extending into South America and involving about 100 km of extension in the Late Jurassic to Early Cretaceous. These factors provide new constraints for the early kinematic evolution of the South Atlantic.