A visibility-based assessment of tsunami evacuation signs in Seaside,Oregon

Tsunami risk mitigation programs often include iconic evacuation signage to direct locals and visitors to safety during a tsunami event. This paper examines sign placement in Seaside, Oregon, from a visibility perspective. It leverages existing visibility analysis methodologies characterize the visibility of the community’s evacuation signage and reveals patterns in the viewable landscape. Additionally, we develop a topologically 3D approach to visibility analysis using raw LiDAR datasets. This applied work situates a discussion on existing patterns of visibility, how to improve existing signage placement, 2D and 3D representation of landscape, and the importance of visibility analysis. This work aims to stimulate discussion and development of hazard research that incorporates a visibility perspective.     

Continental growth and reworking on the edge of the Columbia and Rodinia supercontinents; 1.86–0.9 Ga accretionary orogeny in southwest Fennoscandia

Geological history from the late Palaeoproterozoic to early Neoproterozoic is dominated by the formation of the supercontinent Columbia, and its break-up and re-amalgamation into the next supercontinent, Rodinia. On a global scale, major orogenic events have been tied to the formation of either of these supercontinents, and records of extension are commonly linked to break-up events. Presented here is a synopsis of the geological evolution of southwest Fennoscandia during the ca. 1.9–0.9 Ga period. This region records a protracted history of continental growth and reworking in a long-lived accretionary orogen. Three major periods of continental growth are defined by the Transscandinavian Igneous Belt (1.86–1.66 Ga), Gothian (1.66–1.52 Ga), and Telemarkian (1.52–1.48 Ga) domains. The 1.47–1.38 Ga Hallandian–Danopolonian period featured reorganization of the subduction zone and over-riding plates, with limited evidence for continental collision. During the subsequent 1.38–1.15 Ga interval, the region is interpreted as being located inboard of a convergent margin that is not preserved today and hosted magmatism and sedimentation related to inboard extensional events. The 1.15–0.9 Ga period is host to Sveconorwegian orogenesis that marks the end of this long-lived accretionary orogen and features significant crustal deformation, metamorphism, and magmatism. Collision of an indenter, typically Amazonia, is commonly inferred for the cause of widespread Sveconorwegian orogenesis, but this remains inconclusive. An alternative is that orogenesis merely represents subduction, terrane accretion, crustal thickening, and burial and exhumation of continental crust, along an accretionary margin. During the Mesoproterozoic, southwest Fennoscandia was part of a much larger accretionary orogen that grew on the edge of the Columbia supercontinent and included Laurentia and Amazonia amongst other cratons. The chain of convergent margins along the western Pacific is the best analogue for this setting of Proterozoic crustal growth and tectonism.     

The Oxford Principles

Scientific momentum is increasing behind efforts to develop geoengineering options, but it is widely acknowledged that the challenges of geoengineering are as much political and social as they are technical. Legislators are looking for guidance on the governance of geoengineering research and possible deployment. The Oxford Principles are five high-level principles for geoengineering governance. This article explains their intended function and the core societal values which they attempt to capture. Finally, it proposes a framework for their implementation in a flexible governance architecture through the formulation of technology-specific research protocols.     

The High-Resolution Coronal Imager (Hi-C)

The High-Resolution Coronal Imager (Hi-C) was flown on a NASA sounding rocket on 11 July 2012. The goal of the Hi-C mission was to obtain high-resolution (≈?0.3?–?0.4′′), high-cadence (≈?5 seconds) images of a solar active region to investigate the dynamics of solar coronal structures at small spatial scales. The instrument consists of a normal-incidence telescope with the optics coated with multilayers to reflect a narrow wavelength range around 19.3 nm (including the Fe xii 19.5-nm spectral line) and a 4096×4096 camera with a plate scale of 0.1′′?pixel^?1. The target of the Hi-C rocket flight was Active Region 11520. Hi-C obtained 37 full-frame images and 86 partial-frame images during the rocket flight. Analysis of the Hi-C data indicates the corona is structured on scales smaller than currently resolved by existing satellite missions.     

Predicting June Mean Rainfall in the Middle/Lower Yangtze River Basin

We demonstrate that there is significant skill in the GloSea5 operational seasonal forecasting system for predicting June mean rainfall in the middle/lower Yangtze River basin up to four months in advance. Much of the rainfall in this region during June is contributed by the mei-yu rain band. We find that similar skill exists for predicting the East Asian summer monsoon index(EASMI) on monthly time scales, and that the latter could be used as a proxy to predict the regional rainfall. However, th...     

新疆西天山高硫化型京希-伊尔曼德金矿床的识别标志及其找矿意义

经过详细的野外地质勘查、热液蚀变及蚀变矿物学研究，流体包裹体和同位素研究，首次将西天山京希－伊尔曼德金矿床确定为高硫化型浅成低温热液金矿床。该矿床的主要识别标志为：发育以多孔状石英为特征的硅化蚀变带和高级泥化蚀变带；成矿流体性质为低盐度[W(NaCl)为0.3-4.2%]、低pH值（3－4）和高氧化态；氧同位素δ（^18O)为1.7 ‰-4.3‰,δ(D)为－60‰--80‰。金主要富集在高级泥化带和中心硅化蚀变带内。系统研究和总结了成矿地质－地球化学制约因素以及区域、靶区和勘探区尺度的找矿标志。     

Syntectonic subaqueous mass flows of the Neoproterozoic Otavi Group,Namibia: where is the evidence of global glaciation?

The thick (>1 km) Neoproterozoic Otavi Group of Namibia accumulated after ca. 760 Ma along >700 km of the faulted margin of the Congo Craton. The margin shows a north to south, downbasin transition from a shallow‐water carbonate shelf (Otavi Platform) to offshore deepwater slope (Outjo Basin). Within the latter, the Abenab and Tsumeb Subgroups contain large volumes of poorly sorted breccias, conglomerates and diamictites composed principally of locally derived carbonate. Diamictite facies were reported in the 1930s as tillites left by an ice sheet (although the absence of striated clasts and other key glacial indicators was viewed as problematic). Later workers rejected a glacial origin concluding that Outjo basin facies were deposited as parts of prograding submarine wedges built by mass flows during active rifting. Recently, the Snowball Earth hypothesis has returned to the earlier glacial interpretation; arguing that these strata represent a record of extraordinary late Neoproterozoic glacial and interglacial climates when global temperatures fluctuated by up to 100°C. Facies analysis of breccias, diamictites, conglomerates and sandstone strata of the Otavi Group identifies them as genetically related, subaqueously deposited sediment gravity flows. They lack diagnostic indicators of any one specific climate in source areas. These facies were all deposited in deepwater at the foot of landslide‐prone scarp blocks where debris flows and turbidity currents moved large volumes of coarse, freshly broken carbonate debris produced by faulting. Breccias, diamictites, conglomerates and sandstones occur in composite fining‐ and thinning‐upward bundles that are directly analogous to those reported from many other faulted margins in the Phanerozoic stratigraphic record. These rocks provide no clear sedimentological signature of a glacial source or catastrophic Snowball Earth‐type temperature fluctuations. Instead, they point to a dominant tectonic control on sedimentation related to faulting along the margin of the Congo Craton.     

Ecotourism and mass tourism in Southern Thailand: Spatial interdependence,structural connections,and staged authenticity

The desire to spend leisure time in natural settings represents a key factor behind the recent and rapid growth of ecotourism. A search by ecotourists for remote landscapes and locations has shaped the way in which geographers have defined ecotourism, but few scholars have explored, in detail, the mechanics of the spatial relationship between ecotourism and mass tourism, two forms of travel usually considered mutually exclusive in spatial terms. Using the island of Phuket — southern Thailands premier resort destination — as a case study, this paper investigates the spatial overlaps and connections between ecotourism and mass tourism and tests the assumption that ecotourism and mass tourism must exist spatially apart in order for the former to succeed. Despite Phukets association with mass tourism, and the small physical distances between built-up mass tourist areas and natural ecotourism settings, the communicative staging of natural authenticity allows ecotourism companies to convey geographical remoteness to tourists. Although ecotourism in Phuket must struggle constantly to overcome the perceptual impact of spatial proximity to resort locations, the tourist markets and business networks of the existing mass tourism industry remain crucial to the survival of ecotourism in this region. Thus, contrary to conventional notions that ecotourism and mass tourism must exist as separate entities, this paper argues that an interconnected, symbiotic, and spatially-contiguous relationship between the two is necessary in the case of Phuket.