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  1. Seaward dipping reflectors (SDRs) are large piles of seaward thickening volcanic wedges imaged seismically along most rifted continental margins. Despite their global ubiquity, it is still debated whether the primary cause of SDR formation is tectonic faulting or magmatic loading. To study how SDRs might form, we developed the first two‐dimensional thermomechanical model that can account for both tectonics and magmatism development of SDRs during rifting. We focus here on the magmatic loading mechanism and show that the shape of SDRs may provide unprecedented constraints on lithospheric strength at volcanic rifting margins. For mapping SDRs geometries to lithospheric strength, amore »sequence of model lithospheric rheologies are treated, ranging from analytic thin elastic plates to numerical thick elasto‐visco‐plastic crust and mantle layers with temperature and stress‐dependent viscosity. We then analyzed multichannel seismic depth‐converted images of SDRs from Vøring and Argentinian rifted margins in terms of geometric parameters that can be compared to our model results. This results in estimates for the lithospheric thickness during rifting at the two margins of 3.4 and 5.7 km. The plate thickness correlates inversely with mantle potential temperature at these margins during rifting, as estimated by independent studies.« less
  2. Seaward dipping reflectors (SDRs) are large piles of seaward thickening volcanic wedges imaged seismically along most rifted continental margins. Despite their global ubiquity, it is still debated whether the primary cause of SDR formation is tectonic faulting or magmatic loading. To study how SDRs might form, we developed the first two‐dimensional thermomechanical model that can account for both tectonics and magmatism development of SDRs during rifting. We focus here on the magmatic loading mechanism and show that the shape of SDRs may provide unprecedented constraints on lithospheric strength at volcanic rifting margins. For mapping SDRs geometries to lithospheric strength, amore »sequence of model lithospheric rheologies are treated, ranging from analytic thin elastic plates to numerical thick elasto‐visco‐plastic crust and mantle layers with temperature and stress‐dependent viscosity. We then analyzed multichannel seismic depth‐converted images of SDRs from Vøring and Argentinian rifted margins in terms of geometric parameters that can be compared to our model results. This results in estimates for the lithospheric thickness during rifting at the two margins of 3.4 and 5.7 km. The plate thickness correlates inversely with mantle potential temperature at these margins during rifting, as estimated by independent studies.« less
  3. SITE (Ed.)
    Persons with learning disabilities (LD) are underrepresented in computer science and information technology fields despite the explosion of related career opportunities and interest. In this study, we examine the use of pair programming as a collaborative intervention in with computer programming and compare students with learning disabilities to students who do not have learning disabilities. We concentrate on situational motivation constructs which tap into the desire to meet goals and acquire skills. We find that students with LD and similar students without LD fare the same. For the both groups, three of the four situational motivation subscales increase after themore »introduction of pair programming. The use of pair programming holds promise as an educational intervention for all students including those with learning disabilities.« less