The timing and courses of deglaciations are key components in understanding the global climate system. Cyclic changes in global climate have occurred, with growth and decay of high latitude ice ...sheets, for the last two million years. It is believed that these fluctuations are mainly controlled by periodic changes to incoming solar radiation due to the changes in Earth’s orbit around the sun. However, not all climate variations can be explained by this process, and there is the growing awareness of the important role of internal climate feedback mechanisms. Understanding the nature of these feedbacks with regard to the timing of abrupt global sea-level and climate changes is of prime importance. The tropical ocean is one of the major components of the feedback system, and hence reconstructions of temporal variations in sea-surface conditions will greatly improve our understanding of the climate system. The Integrated Ocean Drilling Program (IODP) Expedition 325 drilled 34 holes across 17 sites in the Great Barrier Reef, Australia to recover fossil coral reef deposits. The main aim of the expedition was to understand the environmental changes that occurred during the last ice age and subsequent deglaciation, and more specifically (1) establish the course of sea-level change, (2) reconstruct the oceanographic conditions, and (3) determine the response of the reef to these changes. We recovered coral reef deposits from water depths down to 126 m that ranged in age from 9,000 years to older than 30,000 years ago. Given that the interval of the dated materials covers several paleoclimatologically important events, including the Last Glacial Maximum, we expect that ongoing scientific analyses will fulfill the objectives of the expedition.
doi: 10.2204/iodp.sd.12.04.2011
Failure to safeguard ancient sites may spring from a fundamental failure of the Western legal system to grasp their significance - why legal and governmental systems of the West need to change in ...order to preserve these places for future generations.
Failure to safeguard ancient sites may spring from a fundamental failure of the Western legal system to grasp their significance - why legal and governmental systems of the West need to change in ...order to preserve these places for future generations.
Failure to safeguard ancient sites may spring from a fundamental failure of the Western legal system to grasp their significance - why legal and governmental systems of the West need to change in ...order to preserve these places for future generations.
Recent studies hypothesize that some submarine slides fail via pressure‐driven slow‐slip deformation. To test this hypothesis, this study derives pore pressures in failed and adjacent unfailed deep ...marine sediments by integrating rock physics models, physical property measurements on recovered sediment core, and wireline logs. Two drill sites (U1394 and U1399) drilled through interpreted slide debris; a third (U1395) drilled into normal marine sediment. Near‐hydrostatic fluid pressure exists in sediments at site U1395. In contrast, results at both sites U1394 and U1399 indicate elevated pore fluid pressures in some sediment. We suggest that high pore pressure at the base of a submarine slide deposit at site U1394 results from slide shearing. High pore pressure exists throughout much of site U1399, and Mohr circle analysis suggests that only slight changes in the stress regime will trigger motion. Consolidation tests and permeability measurements indicate moderately low (~10−16–10−17 m2) permeability and overconsolidation in fine‐grained slide debris, implying that these sediments act as seals. Three mechanisms, in isolation or in combination, may produce the observed elevated pore fluid pressures at site U1399: (1) rapid sedimentation, (2) lateral fluid flow, and (3) shearing that causes sediments to contract, increasing pore pressure. Our preferred hypothesis is this third mechanism because it explains both elevated fluid pressure and sediment overconsolidation without requiring high sedimentation rates. Our combined analysis of subsurface pore pressures, drilling data, and regional seismic images indicates that slope failure offshore Martinique is perhaps an ongoing, creep‐like process where small stress changes trigger motion.
Key Points
Permeability and pressure measurements were made on submarine slide deposits
Near‐lithostatic fluid pressures exist between low‐permeability clays in many slide deposits
Small stress changes can trigger additional shearing and slow‐slip failure in some slide sediments
This study looks at the experiences of people with Asperger’s Syndrome (AS), or High Functioning Autism (HFA), of being helped. The context for this research is Autism Spectrum Conditions are ...recognised as being relatively common, with up to 2% of the population qualifying for an ASC diagnosis. Adults with AS/HFA are recognised as having additional needs, however traditionally services have been difficult to access for people without a learning disability. Research in this area is dominated by quantitative studies, and largely represents the views of professionals and carers. This research seeks the views of people with AS/HFA themselves, to try to discover links between personal understanding of AS/HFA and what additional help is needed. Five participants gave their views via a semi-structured interview, and the resulting data were analysed using Interpretative Phenomenological Analysis (IRA). Three important inter-related themes emerged from this analysis, Conceptualisation of AS/HFA, Relationship of AS/HFA to identity and Conceptualisations of Help. In particular the mediating role of identity in the relationships between personal understandings of AS/HFA and ideas about what is helpful emerged. These findings complement other studies of identity and AS/HFA. Although the participants here varied in what they described as helpful, depending on their conceptualisation of AS/HFA and their sense of identity, several common themes did emerge, notably the need for specialist services, and a greater public awareness of AS/HFA, especially amongst professionals. The clinical implications of this work are also considered, in particular the need for a specialist understanding of anxiety and depression in AS/HFA
PDF
