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Reviewed: Mountains: The Origins of the Earth’s Mountain Systems. By Graham Park. Edinburgh, United Kingdom: Dunedin, 2017. xi + 212 pp. € 42.00, US$ 45.00, ISBN 978-1-78046-0666.6.

International audience; Permafrost degradation is one of the main controlling factors of slope instabilities in glacial and periglacial environments (e.g., Gruber and Haeberli, 2007). In permafrost terrains, ground ice can occur in pores, cavities, voids in soils or rocks, and its thaw can cause slope failures. A plethora of studies exists on the destabilisation of bedrock slopes due to permafrost degradation (e.g., Harris et al., 2001; Magnin et al., 2015). However, the role of thawing ground ice in conditioning and controlling the dynamics of rapid mass movements involving loose deposits is not well constrained, and has been rarely explored through geomorphometric analysis. In this research, we investigate two landslides induced by ground-ice thaw in Iceland, whose source materials comprised ice-cemented talus deposits. We apply quantitative terrain analysis using high-resolution DEMs to describe and quantify the morphometric characteristics of these landslides. Our morphometric approach allows us to show that different dynamic processes were involved during both failures due to the presence of ground ice. This caused the movement to evolve during the failure event, changing the mobility and trajectories of the landslides. Improving our knowledge on this type of landslides through morphometric analysis is important, as it can aid in assessing their hazard and in predicting similar rapid mass movements in comparable settings. References: Gruber, S. and Haeberli, W., 2007. Permafrost in steep bedrock slopes and its temperature-related destabilization following climate change. Journal of Geophysical Research: Earth Surface, 112(F2). Harris, C., Davies, M.C. and Etzelmüller, B., 2001. The assessment of potential geotechnical hazards associated with mountain permafrost in a warming global climate. Permafrost and Periglacial Processes, 12(1), 145-156. Magnin, F., Deline, P., Ravanel, L., Noetzli, J. and Pogliotti, P., 2015. Thermal characteristics of permafrost in the steep alpine rock walls of the Aiguille du Midi (Mont Blanc Massif, 3842 m asl). The Cryosphere, 9(1), 109-121.

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-09-61

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-10-83

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-09-50

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-09-06g

Detailed analytical information for U–Th–Pb analyses

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-09-90

Supplementary field photographs, thin section information, monazite chemical maps and laser-hole photographs for LG-09-01

In a six-month long Innovate UK-funded project (November 2015 – April 2016), we investigated the feasibility of creating a sustainable national 3D ‘virtual field-trips’ (VFT) software service, to support and deliver field trip-based education through a virtual channel in schools and higher education institutions (HEIs). The idea of a 3D VFT service emerged from Virtual Skiddaw App, the 3D virtual geology fieldtrip, of The Open University’s (OU) Open Science Laboratory . In the feasibility project, we (at the OU) (co-investigator) along with Daden (project-lead) and Design Thinkers, UK (co-investigator) we looked into the technical, pedagogical, commercial and service design aspects of the 3D VFT service. \ud \ud In this presentation, we focussed on the pedagogy strand of this feasibility project: pedagogical advantages of 3D VFTs, and the challenges for their adoption in schools and HEIs. \ud \ud We discussed the following: \ud \ud pedagogical underpinnings of 3D virtual environments and 3D VFTs in disciplines such as geology, biology, environmental science/studies and geography which are founded on field observations, exploration and enquiry;\ud \ud potential of integrating VFTs within the curricula in schools and in HEIs;\ud \ud perceptions of educators, students and assessment bodies towards 3D VFTs, and virtual fieldwork, in general; we used the Virtual Skiddaw App in workshops and presentations to illustrate the concept of a 3D VFT;\ud \ud views of stakeholders towards the 3D VFT service: advantages, challenges and their requirements from this service. \ud \ud Our empirical investigations have been user-centred – focussing on the stakeholders and particularly, the end-users such as educators, students and fieldwork specialists, and we have interacted with them via interviews, service design workshops, demonstrations and a survey to elicit their perceptions and requirements.

As a part of The OpenScience Laboratory, (http://www.open.ac.uk/blogs/openscience/), an initiative of The Open University (OU) and The Wolfson Foundation, we are developing a 3D simulation of a Geology field trip based around Skiddaw in the Lake District, using the Unity 3D software (http://unity3d.com/). We are using digital data and imagery to reconstruct the landscape faithfully enough to provide a real sense of presence for the user.\ud \ud The application will be based around a 10km x 10km low/medium detail model of the terrain and LiDAR data around Skiddaw, with overlaid aerial photography, and including walls, trees, buildings etc. \ud \ud The Skiddaw field trip in the Lake District is an integral part of Earth science teaching at the OU; students carry out a real field trip and can also learn about it through DVD activities. The primary objective of developing an authentic 3D interactive simulation has been to provide an immersive experience to the users through sense of space. The virtual embodiment in the form of avatars and the multi-user environment will help give a sense of co-presence and provide opportunities for collaborative learning. The interactions and the learning activities within the 3D environment are designed to mirror the experience of a real field trip. \ud \ud We aim to have an operational 3D virtual geology trip by the time of the Conference in April 2013. During the workshop and through demonstration of the 3D field trip, we plan to address: comparison of the 3D experience with 2D virtual field trips; the role that a 3D virtual geology field trip can play in terms of preparation and reflection before and after a real field trip; and whether and how a 3D simulation helps in gaining geological fieldwork skills and what are the limitations of 3D virtual geology field trips.

Field work was supported by a NERC Research Studentship field grant. In easternmost Bhutan the South Tibetan detachment (STD) is a ductile shear zone that juxtaposes the Radi (or Sakteng) klippe of the Tethyan Sedimentary Series from underlying high-grade Greater Himalayan rocks. In situ LA-ICPMS U-Th-Pb analysis of metamorphic monazite from the immediate footwall and hanging wall of the STD within the shear zone at the base of the klippe, constrains north vergent normal shear to between 25 and 20 Ma. Coeval thrusting on the Main Central Thrust during this time supports a phase of channel flow-viscous wedge model activity, lasting only similar to 3 Ma. Geochronologic data from the eastern Himalaya indicate alternating mechanisms for extrusion of the metamorphic core of the orogen from the Late Oligocene through to the Late Miocene, switching from channel flow-viscous wedge behavior to critical taper-frictional wedge behavior, each phase lasting approximately only 2 to 5 Ma. The tectonic evolution of the eastern Himalaya is comparable to central and western Himalayan tectonics during the Early Miocene, but during the Middle Miocene metamorphism and magmatism in the eastern Himalaya migrated toward the orogenic hinterland, a process not widely documented elsewhere in the Himalaya, thus highlighting the need for an orogenic model in three spatial dimensions. Citation: Chambers, J., R. Parrish, T. Argles, N. Harris, and M. Horstwood (2011), A short-duration pulse of ductile normal shear on the outer South Tibetan detachment in Bhutan: Alternating channel flow and critical taper mechanics of the eastern Himalaya, Tectonics, 30, TC2005, doi:10.1029/2010TC002784. Publisher PDF