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Some parasequences in the interior of the Early Cretaceous isolated carbonate platform, Croatia, which formed under a greenhouse climate, lack the typical regressive tidal flat laminites. Instead, these bioturbated emergent parasequences have burrowed and rooted upper parts, capped with thin greenish paleo­ sols, and are reminiscent of Triassic “Lofer cycles.” We propose that the bioturbated cycle tops reflect coastal salinities that are normal marine, brackish, or metahaline, whereas the transgressive (rare) and abundant regressive tidal flat laminites formed under hypersaline coastal waters. Thus, these features may be used to track gross salinity changes of coastal waters on the platform through time. In addi­ tion, we suggest ways to evaluate whether the salinity changes relate to hypersaline embay­ ments on the platform or changes in the cli­ mate at the parasequence scale. We propose that the bioturbated emer­ gent parasequences could have formed under semiarid conditions, seaward of subtle , shallow embayments on the platform. Con­ temporaneously, in the bayheads, micro­ bial laminites developed—these would require time­equivalent updip and downdip laminate­capped and bioturbated emer­ gence–capped parasequences. However, the para sequences could also have been con­ trolled by climate changes. The laminite­ capped parasequences could have resulted from salinity increase with shallowing of the platform interior under semiarid condi­ tions (stable climate). In contrast, the bio­ turbated emergence–capped parasequences could have formed during times of more humid climate punctuating the overall semi­ arid climate. The humid phase would have favored brackish to normal marine salinities in the coastal zone, along with macrophytes, and intense animal and plant bioturbation, which would suppress development of lami­ nite caps. Thus, these parasequences provide a means of tracking gross salinity of coastal waters, and if climate induced, then they have implications for fluctuating climates in greenhouse worlds.

Dark-gray oolitic units characterized by oversized ooids with primary radial calcite fabrics occur in the interior of the Late Jurassic Late Tithonian, Adriatic Platform, a large Mesozoic, Tethyan isolated platform in Croatia. They differ from open-marine, platform-margin ooid grainstones in their dark color, cerebroid outlines, broken and recoated grains, abundant inclusions, highly restricted biota, and lack of cross-stratifiThey have been interpreted as being of vadose origin (“vadoids”) at tops of upward-shallowing parasequences. However, detailed sections show that most oolitic units occur at bases of precessional parasequences, overlying erosional surfaces on fenestral carbonates. The oolitic units are similar to quiet-water ooids that form today in low-energy settings. They developed in an arid climate during initial transgression of supratidal fl ats, along lowenergy shores seaward of tidal fl ats, and along the margins of restricted lagoons and intertidal ponds. Superimposed fenestral fabrics, meniscus micrite cements, and grain breakage occurred as they aggraded to high-tide level and were subjected to wetting and drying, thermal expansion and contraction, and wind transport. They migrated landward with transgression, forming extensive sheets, and were overlain by subtidal lagoonal facies that shallow up into fenestral carbonates. These distinctive facies may have been overlooked in the geological record, or their geological distribution requires juxtaposition of calcite seas, high-calcite supersaturation states, arid climate, and presence of fl at-topped carbonate platforms in a greenhouse world.