Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depress...Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depressions of about 250 m in width and several kilometers in length are areas of focused gas discharge indicated by bubble-release into the water column and methane enriched pore waters. Sparker seismic profiles running perpendicular and parallel to the coast, show gas migration pathways and trapped gas underneath these depressions with bright spots and seismic blanking. The data indicate that upward gas migration is the initial reason for fracturing sedimentary layers. In the top sediment where two young stages of landslides can be detected, the slopeparallel sediment weakening lengthens and deepens the surficial fractures, creating the elongated depressions in the seafloor supported by sediment erosion due to slope-parallel water currents.展开更多
This study was based on self-report of a MOOC school-based college English classroom teaching practice flip. Firstly, it is based on the analysis of the typical characteristics of MOOC leveraging MOOC college English ...This study was based on self-report of a MOOC school-based college English classroom teaching practice flip. Firstly, it is based on the analysis of the typical characteristics of MOOC leveraging MOOC college English courses on the basis of the next report on the concrete practice of school-based college English MOOC construction and flipped classroom teaching. Quantitative and qualitative data on learner feedback in the survey analysis shows that based MOOC flip mode is suitable for classroom teaching college English teaching, MOOC and flipped classroom have been highly recognized by students, which gives full play to both collaborative IT and foreign language teaching the depth of integration of blended learning potential.展开更多
基金funded by the European project EUROFLEETS (Seventh Framework Programme, No. 228344)
文摘Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depressions of about 250 m in width and several kilometers in length are areas of focused gas discharge indicated by bubble-release into the water column and methane enriched pore waters. Sparker seismic profiles running perpendicular and parallel to the coast, show gas migration pathways and trapped gas underneath these depressions with bright spots and seismic blanking. The data indicate that upward gas migration is the initial reason for fracturing sedimentary layers. In the top sediment where two young stages of landslides can be detected, the slopeparallel sediment weakening lengthens and deepens the surficial fractures, creating the elongated depressions in the seafloor supported by sediment erosion due to slope-parallel water currents.
文摘This study was based on self-report of a MOOC school-based college English classroom teaching practice flip. Firstly, it is based on the analysis of the typical characteristics of MOOC leveraging MOOC college English courses on the basis of the next report on the concrete practice of school-based college English MOOC construction and flipped classroom teaching. Quantitative and qualitative data on learner feedback in the survey analysis shows that based MOOC flip mode is suitable for classroom teaching college English teaching, MOOC and flipped classroom have been highly recognized by students, which gives full play to both collaborative IT and foreign language teaching the depth of integration of blended learning potential.