Concerning the environmental interpretation of "Lo Hueco", the entire succession seems to correspond to a near coast muddy flood plain crossed by sandy channels, which suffered successive depositional intervals (mainly clayey but, occasionally, also chalky or sandy) and syn- or early post-depositional periods of sulphatation and ferruginization. This continental plain (with abundance of terrestrial plants, invertebrates and vertebrates) apparently registered intermittent intervals of aquatic influence (burrows, bivalves, fishes, bothremydid and pancryptodiran turtles, crocodiles), clearly evident in the G1 and G2 levels, the C structure and the S1 and S2 intervals, and of partial or total desiccation (roots), especially manifest in R1 and R2. The same aquatic influence probably was mainly of fresh water (unionid bivalves), but occasionally also was of marine or brackish water (Thalassinoides, herringbone or chevron bedding, pancryptodiran turtles). This aquatic influence seemingly suffered notable oscillations in volume and energy. Apparently, during the high energy intervals, some of the registered sediments and organisms were transported and fragmented, mainly across a channel (C structure), but also across its overbank zones (G1 and G2 levels). During the diminishing energy intervals, some of the registered sediments and organisms were orientated, parallel and perpendicular to the axis of the channel, and deposited on the overbank zones and inside the channel. During the low energy intervals, mainly on the overbank zones, relatively isolated water masses could be formed, acting maybe as miring areas. Progressively, these areas might give place to trampling areas (oblique or infilled breakages in vertebrate remains near the C structure). Finally, during the intervals without aquatic influence, the environment of "Lo Hueco" site was partially or totally dried up and vegetation settled over the muddy plain (R1 and R2 levels)"
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Cita: Segura et al. (2010) Depositional environments in the "Lo Hueco" palaeontological site (Upper Cretaceous, Cuenca, Spain). Libro de resúmenes del 4º Congreso Francés de Estratigrafía.
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