Middle Jurassic but rose considerably towards the Late Jurassic, deepening the marine trenches between continents. Depositional environment The sedimentary rocks and fossils record a repeated shift from shallow marine to tidal flat environments indicating that the strata of the Tendaguru Formation were deposited near an oscillating strandline which was controlled by sea level changes. The three dinosaur-bearing members are continental to marginal marine and the three sandstone-dominated members are marginal marine in origin. Nerinella Member The composition of benthic molluscs and foraminifera, euhaline to mesohaline ostracods, and dinoflagellate assemblages indicate marine, shallow water conditions for the Nerinella Member, in particular for the lower part. Sedimentation occurred as tidal channel fills, subtidal and tidal sand bars, minor storm layers (tempestites), and beach deposits. Overall, the Nerinella Member represents a variety of shallow subtidal to lower intertidal environments influenced by tides and storms. Middle Dinosaur Member The sedimentological characteristics of the basal part of the Middle Dinosaur Member suggest deposition on tidal flats and in small tidal channels of a lagoonal paleoenvironment. The ostracod Bythocypris sp. from the member indicates polyhaline to euhaline conditions. Slightly higher up, a faunal sample dominated by the bivalve Eomiodon and an ostracod assemblage composed of brackish to freshwater taxa is indicative of a brackish water paleoenvironment with distinct influx of freshwater as revealed by the nonmarine ostracod genus Cypridea, charophytes, and other freshwater algae. The paleoenvironment of the ostracod assemblages of the Middle Dinosaur Member changed upsection from a marine setting in the basal parts through alternating marine-brackish conditions to freshwater conditions in the higher parts of this member. The highly sporadic occurrence, in this part of the section, of molluscs typical of marginal marine habitats indicates only a very weak marine influence, at sabkha-like coastal plains with ephemeral brackish lakes and ponds are recorded in the upper part of the Middle Dinosaur Member. This part also contains pedogenic calcretes indicating subaerial exposure and the onset of soil formation. The calcrete intraclasts within adjacent sandstone beds testify to erosive reworking of calcrete horizons. The presence of crocodyilforms indicates freshwater to littoral environments and adjacent terrestrial areas. Indotrigonia africana Member The coarse-grained sandstone of the lower part of the Indotrigonia africana Member that shows highly variable transport directions is interpreted as deposits of large tidal channels. Grain-size, large-scale sedimentary structures, and the lack of both trace fossils and epifaunal and infaunal body fossils suggest high water energy