Abstract The post-obduction formations of Grande Terre, New Caledonia, comprise igneous intrusions, regolith cover, and marine and terrestrial sedimentary rocks. Two restricted Late Oligocene granitoid bodies are intruded into the Peridotite Nappe and its substrate in the south of the island. Thick regolith cover developed over the Peridotite Nappe from the Late Oligocene or earlier. The Népoui Group comprises Late Oligocene–Early Miocene mixed marine carbonate and siliciclastic deposits. It mainly reworks the Peridotite Nappe and its regolith cover. Its development pattern is mainly controlled by tectonic uplift and subsidence. The Gwa N'Doro Formation on the eastern coast and the Fluvio-lacustrine Formation in the south are remnants of the Miocene–Present river network. Offshore, thick Oligocene to Neogene sedimentary successions are imaged by seismic surveys on the margins of Grande Terre, although these successions have not been drilled and remain undated. Several dredges have recovered shallow Miocene sedimentary rocks, indicating substantial Neogene subsidence. Quaternary formations are represented inland by aeolianite, vertisols and calcrete and offshore by the large barrier reef–lagoon complex, the onset of which is dated at c. 400 ka. This chapter discusses the different models proposed for the post-obduction evolution of Grand Terre.

Abstract The role of climate change in driving alluvial-fan sedimentation is hard to assess in pre-Quaternary successions, for which detailed chronologies and climate-proxy records cannot be easily established. In the Teruel Basin (Spain), high-resolution (10 4 –10 5 years) chronological and palaeoclimatic information was derived by orbital tuning of Late Miocene mudflat to ephemeral-lake deposits. The semi-arid palaeoclimate made this low-gradient, basinal environment sensitive to thresholds in the local hydrological balance. Basic facies rhythms are attributed to alternating, relatively humid/arid phases controlled by the climatic precession cycle. The lower stratigraphic interval of this reference section interfingers with distal, coarse-clastic beds from a coeval alluvial fan. The consistent interdigitation of debris-flow deposits with distal strata indicative of arid-to-humid climate transitions shows that fan sedimentation was regulated by climate cyclicity. In particular, the largest volumes of terrigenous debris were shed from the fan onto adjacent mudflats during transitions to relatively humid periods with pronounced seasonality, during precession minima. Distal to medial sections within alluvial-fan outcrops also feature prominent, laterally continuous alternations of coarse- and fine-clastic packages. This high degree of architectural organization, uncommon in fan successions, and stratigraphic relationships with the reference section suggest orbitally controlled climate change to have been the forcing mechanism.