Laterites preserved on both sides of the Western Ghats Escarpment of Peninsular India have formed by long-term lateritic weathering essentially after India-Seychelles continental break up following Deccan Traps emplacement (c. 63 Ma ago). Supergene manganese ores of the Western Ghats were formed on Late Archean manganese protores. Among Mn oxides composing the ores, cryptomelane (K-rich Mn oxide) was characterized and dated by 40 Ar/ 39 Ar geochronology. Measured ages complement those previously obtained in other South-Indian manganese ores from the hinterland plateau (Bonnet et al., 2016) and further document three major weathering periods, c. 53-44 Ma, c. 39-22 Ma, and c. 14-10 Ma, the later being documented for the first time in India. These periods coincide with global paleoclimatic proxies and date the lateritic weathering of three successive paleolandscapes of the Western Ghats that evolved under slow denudation (c. 8 m/myr) over the last 44 Myr and were mostly incised during the Neogene (< 22 Ma). That indicates the Western Ghats are a relict of a South Indian plateau preserved at the headwaters of very long east-flowing river systems and above the Western Ghats escarpment. Topography and denudation history of this landscape do not require Neogene tilt of the Peninsula as recently proposed.
Terrestrial ecosystems from the Lower Cretaceous of Europe and bonebeds formed in swampy environments are poorly known. The Berriasian‐early Valanginian Angeac‐Charente site in France represents an example of both. Nine field campaigns have yielded thousands of fossils of over a hundred taxa, including 16 taxa from vertebrate macroremains with numerous trample and crocodile bite marks; 22 taxa from the abundant vertebrate microremains; >10 vertebrate coprolite morphotypes with plant and vertebrate inclusions; abundant sauropod and stegosaur tracks including some preserved in ‘4‐D’; termite coprolites; mollusc moulds; ostracods and plants, including coniferous wood, cones, leaves and cuticle fragments, charophytes and pollen. The richness, diversity and preservation of the fossils qualify the site as a fossil‐Lagerstätte. The site represents a ‘snapshot’ into a Lower Cretaceous ecosystem. This is supported by REE analyses of biogenic apatite and sediment samples, the fossils being found in a single stratigraphical interval and the record of sedimentological and taphonomic ‘frozen scenes’. The Angeac‐Charente bonebed is highly diverse, dominated by an ornithomimosaur taxon, and contains both macro‐ and microfossils. This indicates a complex formation, likely primarily influenced by ecological and biologic processes, but also significant physical processes. These include crocodyliform predation and/or scavenging on turtles, ornithomimosaurs and fishes; probable mass mortality occurrence of an ornithomimosaur herd; possible social behaviour of stegosaurs; limited hydraulic transport of most sauropod bones and intense dinoturbation.
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