The Kutai Basin (East Kalimantan, Indonesia) contains a rich and well-preserved Miocene fossil record of small patch reefs that developed under the influence of high siliciclastic input associated with the progradation of the Mahakam Delta. In this study, we reconstruct the biodiversity and paleoenvironments on one of these delta-front, mixed carbonatesiliciclastic systems that developed at the Serravallian-Tortonian boundary near the city of Samarinda. In two newly exposed sections, we analyzed the sedimentology and distribution of the main fossil biota including corals, foraminifers, coralline algae, and bryozoans. Seven facies are herein defined, including two dominated by platy corals and two by larger benthic foraminifera. Facies distributions were driven by changes in depth and variations in terrigenous input within a range of delta-front habitats. Despite the turbid conditions, fossil assemblages are highly diverse, including 69 coral species and 28 bryozoan species that occur in coral-dominated facies. Crustose coralline algae were mainly associated with the coral-dominated facies. Larger benthic foraminifera showed broader ecological tolerance within the range represented in the studied sections and thus are common in most facies. These diverse patch reef ecosystems were able to cope with high siliciclastic input during the early development of the Miocene coral reef biota.

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Sixteen dinosaur footprints are exposed along the upper-bedding surface of a single Lower Hauterivian limestone layer in Palud cove (western Istria, Croatia). This footprint-bearing horizon is part of the thick Mesozoic stratigraphic succession of the Adriatic-Dinaridic Carbonate Platform. The Palud site section is characterized by peritidal (shallow subtidal to intertidal) limestone with several shallowing-upward cycles composed of mudstone, peloidal wackestone/packstone, peloidal packstone/grainstone and fenestral mudstone/wackestone with common geopetal infill. The Early Hauterivian age of these deposits is based on their microfossil content, which is dominated by ostracods, benthic foraminifera and calcareous green algae (Dasycladales). The footprints are circular to elliptical in shape, with no distinct digit impressions (with one possible exception), and with average length of 26 cm. Most footprints have a well-defined expulsion rim produced by the compression and displacement of the waterlogged substrate caused by the feet of the dinosaurs. All of the footprints are nearly the same shape and size, which indicates that they were produced by the same kind of trackmaker-likely a sauropod dinosaur. These animals left their footprints on the top of an intertidal and shallowing-upward succession during ephemeral subaerial exposure of the fine-grained carbonate sediment.

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