the badamu formation (upper toarcian-middle bajocian) mainly consists of limestone and shale and has is cropped out in east of iran. the badamu formation conformably overlays shemshak formation and is underlaid sharply by hojedk formation in kerman area and is underlaid gradually by baghamshah formation in tabas and southern khorasan areas. the aim of this work is petrographical study of rocks ...

BACKGROUND The Middle Jurassic was a critical time in the evolutionary history of ichthyosaurs. During this time interval, the diverse, well-studied faunas of the Lower Jurassic were entirely replaced by ophthalmosaurids, a new group that arose sometime prior to the Aalenian-Bajocian boundary and by the latest middle Jurassic comprised the only surviving group of ichthyosaurs. Thus, the Middle ...

The facies changes, tectonics and magmatism across the Triassic–Jurassic boundary in the southern Tethyan margin have been studied in Egypt, Sudan, Jordan and Saudi Arabia. In Saudi Arabia and Jordan an unconformable contact is recognized between the Upper Triassic and Lower Jurassic rocks. This unconformity surface is marked by the truncation of the fluvial clastics of the uppermost Triassic b...

The Lower Jurassic Navajo Sandstone of northern Arizona and southern Utah has yielded a diverse assemblage of late Early Jurassic terrestrial tetrapods from eolian and associated paleoenvironments. Although rare, vertebrate body fossils are represented by specimens of tritylodonts, crocodylomorphs, sauropodomorphs, and basal theropods (including Segisaurus halli). The vertebrate ichnofossil rec...

Upper Jurassic strike-slip intra-arc basins formed along the axis of earlier Lower to Middle Jurassic extensional intra-arc basins in Arizona. These strike-slip basins developed along the Sawmill Canyon fault zone, which may represent an inboard strand of the Mojave-Sonora megashear system that did not necessarily produce large-scale translations. Subsidence in the Lower to Middle Jurassic exte...

The structural configuration of SW Japan mainly reflects a late Jurassic-early Cretaceous orogeny. The region is divided into an inner belt and an outer belt, on the Japan sea and Pacific ocean sides respectively, by a strike-slip fault, the Median Tectonic Line (MTL). Both consist of a series of stacked nappes. The inner belt is divided into a Jurassic olistostrome known as the Tanba zone and ...

BACKGROUND The early evolution of sauropod dinosaurs is poorly understood because of a highly incomplete fossil record. New discoveries of Early and Middle Jurassic sauropods have a great potential to lead to a better understanding of early sauropod evolution and to reevaluate the patterns of sauropod diversification. PRINCIPAL FINDINGS A new sauropod from the Middle Jurassic of Niger, Spinop...

The late Middle Jurassic–early Eocene (;120 m.y.) sediment-accumulation history of the Cordilleran foreland basin in northern Utah exhibits a sigmoidal pattern on a rate vs. time plot, with moderate rates of accumulation during late Middle Jurassic, very low net rates during Late Jurassic–earliest Cretaceous, increasingly rapid rates during Earlymiddle Cretaceous, and low rates during Late Cret...