TECTONIC EVOLUTION OF THE FOOTHILLS BELT AND FORELAND AREAS OF THE TAURUS OVERTHRUST BELT, SOUTHEAST TURKEY

In the Foothills belt of the Taurus overthrust belt in southeast Turkey, a number of Late Cretaceous to late Miocene southward-migrating flexural foredeeps were generated in response to contractional and crustal loading events occurring along their internal margins. From a study of the disposition and deformation of the foreland basin sediments, the relative importance of the following events can be demonstrated: (1) A thin-skinned shortening of the northward-facing Arabian passive margin, which occurred during closure of Neotethys and ophiolitic obduction during the Late Cretaceous. Molasse-type marine and nonmarine sediments generated during this event are restricted to a narrow east-west-trending, southward-migrating flexural foredeep of Campanian to Paleocene age. (2) A late Miocene contractional event related to continental collision between the Arabian and Eurasian plates. The molasse sediments generated by this event are still being deposited and are volumetrically similar to those generated by the Late Cretaceous event. The importance of this late Miocene contractional event is emphasized, and its structural expression differs throughout the North Arabian platform. In the Foothills belt domain, the structures are largely thin skinned and the Late Cretaceous thrust front has been rejuvenated. In the foreland area to the south, the late Miocene shortening has a much deeper structural expression, reactivating old extensional faults and resulting in the inversion of Paleozoic- and Mesozoic-age half-graben basins up to 400 km south of the Taurus thrust front

Gypsum Karst Landscape in the Sivas Basin

The Tertiary Sivas Basin, Central Anatolia, includes one of the most outstanding gypsum karst terrains in the world, covering an area of 2140 km2. This gypsum karst significantly contributes to enrich the diversity of karst landscapes in Turkey and constitutes an excellent natural laboratory for understanding their evolution because it develops and degrades much faster than carbonate karst landscapes. The ENE–WSW trending Sivas gypsum karst terrain is 280 km long and 55 km wide. The karst landscapes are mainly developed on Oligocene gypsum deposits. Sivas gypsum karst terrain has a wide variety of well-developed karst features such as karren, different types of dolines (solution, collapse and suffosion), blind valleys, karst springs, swallow holes (ponors), karstified paleo-valleys, caves, unroofed caves, natural bridges, gorges, uvalas and poljes. Solution dolines, which riddle a large part of the area, are the most common landform. The Kızılırmak River and its tributaries drain the Sivas Basin. Therefore, Quaternary evolution of the Kızılırmak River has played an important role in the long-term evolution of the karst landscape in the basin. Karst development in some parts of the basin has also been affected by halokinetic structures

Enigmatic Fossils from the Lower Carboniferous Shrimp Bed, Granton, Scotland

The Lower Carboniferous (Visean) Granton Lagerstätte (Edinburgh, Scotland) is principally known for the discovery of the conodont animal, but has also yielded numerous crustaceans and other faunas. Here we report on small branching colonies, reaching 10 mm in length. They are small, erect, arborescent, and irregularly branched with predominant monopodial and dichotomous growth. They bud in a single plane. In one specimen the wall microstructure is well preserved and it is composed of evenly spaced, linear fibers, running parallel to the axis of the stems, and connected by transverse bars. We discuss possible biological affinities of these organisms; we consider algal, poriferan, hydrozoan and bryozoan affinities. The general pattern of branching, presence of fan-like structures (interpreted here as possible gonophores) and microstructure suggests affinity to Hydrozoa, affinity to non-calcifying algae is less likely. Assuming hydrozoan nature; the microstructure might suggest affinities with the extant family Solanderiidae Marshall, 1892 that possess an internal chitinous skeleton. The EDS analysis shows that fossils discussed here are preserved as phosphates. The skeletons were probably not mineralized, the presence of phosphorus suggests that the colonies were originally composed of chitin. We describe these organisms as Caledonicratis caridum gen. et sp. nov. (Solanderiidae?, Capitata?). Colonies of C. caridum gen et. sp. nov. sometimes encrust the exuviae of crustaceans, which very probably lived in fresh to brackish water thus indicating a likely habitat of Caledonicratis