Thermal-mechanical response to simple shear extension

The mechanism of extension in the continental crust is apparently much more complex than that acting in the oceanic lithosphere. Recently, Wernicke has proposed that a significant fraction of extension in the continental lithosphere may occur by a simple shear mechanism along discrete fault/shear zones which cut the crust, and perhaps extend into the uppermost mantle. Clearly much of the surface evidence for extension supports this concept, but the depth extent of simple shear extension in the continental crust is unclear. Using numerical simulations, the thermal and associated mechanical behavior of the continental lithosphere in response to lithosphere extension along a low-angle simple shear zone which cuts through the lithospheric plate was determined in order to evaluate the resolving ability of thermal (heat flow and metamorphic P-T-time paths) and elevation observations in constraining the mode of continental extension

Microseismicity and Creeping Faults: Hints from Modeling the Hayward Fault

Abstract Creeping segments of strike-slip faults are often characterized by high rates of microseismicity on or near the fault. This microseismicity releases only a small fraction of the slip occurring on the fault and the majority of the accumulating elastic strain is released either through aseismic creep or in rare large events. Distinguishing between creeping or non-creeping patches on faults and determining the resulting accumulated slip deficit is important in assessing the seismic hazard associated with a fault. Unfortunately, surface creep data alone are insufficient to constrain the creep at depth on the fault. Here we analyze the possibility of using microseismicity as a further constraint. An analysis of the accumulation of Coulomb stress associated with the fault creep indicates that the transition from creeping regions to locked patches has the potential to affect the local seismicity pattern. Precise relative relocations of the microseismicity of the Hayward fault [1] [F. Waldhauser, W.L. Ellsworth, Fault structure and mechanics of the Hayward Fault, California, from double-difference earthquake locations, J. Geophys. Res. 107(3), doi:10.1029/2000JB000084, 2002 indicate that a fraction of the events repeat, indicating recurrent ruptures of the same small patch. A comparison of the creeping pattern resulting from a Finite Element deformation Model with this precisely relocated microseismicity indicates that the non-repeating earthquakes mainly occur in the transitional zones from creeping to locked patches, while recurrent (repeating) earthquakes cluster in high creep-rate regions. Building from this observation, we have developed an analysis approach to better define patterns of creep, and thus the slip deficit, on the Hayward fault. Additionally this creep rate and its spatial pattern on the fault vary as a function of time after the system is loaded by earthquakes on the locked patches.

Evaluating the specialist palliative care clinical nurse specialist role in an acute hospital setting: a mixed methods sequential explanatory study.

Special palliative care is provided in a range of settings including a patient's home (their primary place of dwelling), a hospice in-patient unit, or an acute hospital. The aim of the study was to evaluate the role of the specialist in palliative care clinical nurse specialist (SPC CNS) role in an acute hospital setting. This study was conducted using a mixed methods sequential explanatory approach in two phases; phase 1 involved completion of a study questionnaire (n = 121) and phase 2 involved part-taking in a focus group (n = 6) or individual interview (n = 4). Phase 1 results indicated that respondents held positive attitudes towards the Specialist Palliative Care Clinical Nurses Specialist (SPC CNS) in relation to clinical care, education and patient advocacy. Phase 2 qualitative findings identified the importance of the role in terms of symptom management, education and support. This study provides an evaluation of a SPC CNS role since it was established in an acute hospital setting. The evidence indicates that there is a varied understanding of the role of the SPC CNS. The role was seen as an important one particularly in terms of referrals to and support provided by the SPC CNS, as well as recognition of the importance of the role is providing ongoing education to staff

Uninterested youth? Young people's attitudes towards party politics in Britain

Following the outcome of the 2001 and 2005 General Elections, when the numbers of abstainers outweighed the numbers of Labour voters on both occasions, much attention has focused upon the state of British democracy and how to enthuse the electorate, especially young people. While the government is exploring ways to make the whole process of voting easier, it may be failing to tackle the real problem - that youth appear to find the business of politics uninviting and irrelevant. This paper examines data derived from a nationwide survey of over 700 young people in order to shed light on what lies at the heart of young people's apparent disengagement from formal politics in Britain - political apathy or a sense of political alienation. The findings reveal that they support the democratic process, but are sceptical of the way the British political system is organised and led, and are turned off by politicians and the political parties. However, there is no uniform youth orientation to politics, and the data indicate that views differ according to social class, educational history, and also gender. However both ethnicity and region of the country in which young people live seem to have little influence in structuring political attitudes and behaviour

Stigma narratives: LGBT transitions and identities in Malta

This article is available open access through the publisher’s website at the link below. Copyright @ 2011 A B Academic Publishers.This article considers narratives of transition experiences of a group of Lesbian, Gay, Bisexual and Transgender (LGBT) young people in Malta. The article draws on Goffman's concept of stigma and uses this to explore transitions in a society that retains some traditional characteristics, particularly the code of honour and shame, although mediated by aspects of modernity. Interviews were undertaken with 15 young people with the goal of producing narratives. The article analyses the experience of stigma, its effects and how young people manage its consequences. It concludes by drawing attention to the pervasive nature of stigma and the importance of structure, agency and reflexivity in youth transitions. In particular stigma remains an important feature of societies in which hetero-normative sexuality remains dominant

Effect of the Cretaceous Serra Geral igneous event on the temperatures and heat flow of the Parana Basin, southern Brazil

We investigate the effects of the cooling of intrusive and extrusive igneous bodies on the temperature history and surface heat flow of the Parana Basin. The Serra Geral igneous event (130–135 Ma) covered most of this basin with flood basalts. Associated with this event numerous sills and dykes intruded the sediments and basement, and extensive underplating may have occurred in the lower crust and upper mantle beneath the basin. We develop an analytical model of the conductive cooling of tabular intrusive bodies and use it to calculate temperatures within the sediments as a function of time since emplacement. Depending on the thickness of these igneous bodies and the timing of sequential emplacement, the thermal history of a given locus in the basin can range from a simple extended period of higher temperatures to multiple episodes of peak temperatures separated by cooling intervals. The cooling of surface flood basalts, sills and dykes is capable of maintaining temperatures abovc the normal geothermal gradient temperatures for a few hundred thousand years, while large-scale underplating may influence temperatures for up to 10 million years. We conclude that any residual heat from the cooling of the Serra Geral igneous rocks has long since decayed to insignificant values and that present-day temperatures and heat flow are not affected. However, the burial of the sediments beneath the thick basalt cap caused a permanent temperature increase of up to 50°C in the underlying sediments since the beginning of the Cretaceous.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72088/1/j.1365-2117.1994.tb00087.x.pd

Opportunities and challenges of the digital lifespan:views of service providers and citizens in the UK

<p>Information about UK citizens’ use of digital technologies is often expressed in statistics – x% lack Internet access; y% get online to engage in online banking, update social media sites, or participate in online auctions. There are many social implications to digital technology use, however – individuals may communicate online as a major way to stay in touch with friends and family, and as Internet access rises and government and public sector budgets shrink, online services become an increasingly attractive way for government and public sector service providers to communicate with citizens. This paper presents selected results of an exploratory study designed to investigate the digital personhood of UK citizens through interviews with participants at three life transitions: leaving secondary school, becoming a parent, and retiring from work. Digital personhood in this paper implies identity information online, and some interaction with others around that information. We then report on our presentation of a selection of these results to thirteen stakeholders who represented UK government departments, public sector organisations, and industry. We found that citizen and stakeholder concerns were quite different, especially at the new parent life transition, and that stakeholders tended to <i>underestimate</i> the willingness and ability of citizens to become involved online with the government and public sector, and <i>overestimate</i> citizens’ vulnerability online. Future research should investigate practical strategies for increasing communication between stakeholders and citizens, and also how to encourage stakeholders to work together to benefit their common clientele – the citizens.</p