Revised Lithostratigraphy of the Sonsela Member (Chinle Formation, Upper Triassic) in the Southern Part of Petrified Forest National Park, Arizona

BACKGROUND: Recent revisions to the Sonsela Member of the Chinle Formation in Petrified Forest National Park have presented a three-part lithostratigraphic model based on unconventional correlations of sandstone beds. As a vertebrate faunal transition is recorded within this stratigraphic interval, these correlations, and the purported existence of a depositional hiatus (the Tr-4 unconformity) at about the same level, must be carefully re-examined. METHODOLOGY/PRINCIPAL FINDINGS: Our investigations demonstrate the neglected necessity of walking out contacts and mapping when constructing lithostratigraphic models, and providing UTM coordinates and labeled photographs for all measured sections. We correct correlation errors within the Sonsela Member, demonstrate that there are multiple Flattops One sandstones, all of which are higher than the traditional Sonsela sandstone bed, that the Sonsela sandstone bed and Rainbow Forest Bed are equivalent, that the Rainbow Forest Bed is higher than the sandstones at the base of Blue Mesa and Agate Mesa, that strata formerly assigned to the Jim Camp Wash beds occur at two stratigraphic levels, and that there are multiple persistent silcrete horizons within the Sonsela Member. CONCLUSIONS/SIGNIFICANCE: We present a revised five-part model for the Sonsela Member. The units from lowest to highest are: the Camp Butte beds, Lot's Wife beds, Jasper Forest bed (the Sonsela sandstone)/Rainbow Forest Bed, Jim Camp Wash beds, and Martha's Butte beds (including the Flattops One sandstones). Although there are numerous degradational/aggradational cycles within the Chinle Formation, a single unconformable horizon within or at the base of the Sonsela Member that can be traced across the entire western United States (the "Tr-4 unconformity") probably does not exist. The shift from relatively humid and poorly-drained to arid and well-drained climatic conditions began during deposition of the Sonsela Member (low in the Jim Camp Wash beds), well after the Carnian-Norian transition

The 2010 Hans Cloos lecture : the contribution of urban geology to the development, regeneration and conservation of cities

Urban geology began to develop in the 1950s, particularly in California in relation to land-use planning, and led to Robert Legget publishing his seminal book “Cities and geology” in 1973. Urban geology has now become an important part of engineering geology. Research and practice has seen the evolution from single theme spatial datasets to multi-theme and multi-dimensional outputs for a wide range of users. In parallel to the development of these new outputs to aid urban development, regeneration and conservation, has been the growing recognition that city authorities need access to extensive databases of geo-information that are maintained in the long-term and renewed regularly. A further key advance has been the recognition that, in the urban environment, knowledge and understanding of the geology need to be integrated with those of other environmental topics (for example, biodiversity) and, increasingly, with the research of social scientists, economists and others. Despite these advances, it is suggested that the value of urban geology is not fully recognised by those charged with the management and improvement of the world’s cities. This may be because engineering geologists have failed to adequately demonstrate the benefits of urban geological applications in terms of cost and environmental improvement, have not communicated these benefits well enough and have not clearly shown the long-term contribution of geo-information to urban sustainability. Within this context future actions to improve the situation are proposed

Eltrombopag before procedures in patients with cirrhosis and thrombocytopenia

Eltrombopag is an oral thrombopoietin-receptor agonist. This study evaluated the efficacy of eltrombopag for increasing platelet counts and reducing the need for platelet transfusions in patients with thrombocytopenia and chronic liver disease who are undergoing an elective invasive procedure

The transcriptional regulation of pluripotency

10.1038/cr.2012.172Cell Research23120-3