Iron precipitation in a natural CO2 reservoir: Jurassic Navajo Sandstone in the northern San Rafael Swell,UT, USA

Diagenetic iron (oxyhydr)oxide minerals are common precipitates expected in CO₂ reservoirs, and these minerals record fluid flow for application to carbon capture and sequestration (CSS). Multiple mineralogy and spectroscopy analyses on a pore to meter scale characterize a well‐exposed, lithologically controlled, iron (oxyhydr)oxides reaction front in the Jurassic Navajo Sandstone. Dolomite is the most prevalent cement (up to 23 area%), followed by only several percent or less of iron (oxyhydr)oxides, kaolinite, illite, and gypsum cements. Bulk geochemistry based on diagenetic mineralogies in the reaction front is compared with the water chemistry from nearby modern spring effluent emanating from the Navajo Sandstone to conclude that similar fluids (i.e., CO₂‐charged, saline waters containing hydrocarbons) are responsible for the precipitation. A second comparison of bulk geochemistry and diagenetic mineralogies of the reaction front with data from other abundant Navajo Sandstone concretions in the Spencer Flat region (in south central Utah) shows that reservoir fluids likely vary spatially and temporally in the porous and permeable Navajo Sandstone. CO₂ injection into porous and permeable, quartz arenite, saline aquifers will likely result in minor clay and abundant dolomite precipitation that will significantly decrease porosity.     

Screening Singapore: The Cinematic Landscape of Eric Khoo's Be With Me

This paper investigates the mutually constitutive relationship between the context of film production and the composition and content of images produced. Singapore film director Eric Khoo is central to our investigation, and his 2005 film Be With Me is a key example of how Singapore's ongoing urban redevelopment to become a world city reflexively shapes the style and appearance of the city‐state projected in the film. Singapore's history as a developmental state, its pervasive influence on the public and private spaces of its citizens, and recent state‐led initiatives to nurture the arts and media sectors all make it an ideal site to examine the relations between the cinema and space. Be With Me also lends itself to spatial analysis as its mise‐en‐scène is a geography of the life course: particular parts of the city are ‘cast’ as spaces of youth, middle, and old age. We elaborate how the landscapes deployed in the film are simultaneously constituted through state policies, mise‐en‐scène, and gender/age/class considerations. In so doing we show how Khoo's vision of the city‐state has altered since his emergence as a film director in the 1990s: from an oppressed site of hyper‐modernity to a more ambivalent ‘globalised’ built environment in which marginalised or liminal urban spaces for sensuous life and hope for human connection can be experienced.     

Dynamics of Land Surface Temperature in Response to Land‐Use/Cover Change

In this study, we employed Geographical Information Systems and remote sensing techniques to investigate the impact of land‐use/cover change on land surface temperature (LST) in a rapidly urbanisation city, Kunming in south‐west China. Spatial patterns of LST and land use for 1992 and 2006 were derived from Landsat images to examine how LST responded to urban growth. Remote sensing indices were used to quantify land‐use types and employed as explanatory variables in LST modelling. The geographically weighted regression (GWR), a location dependent model, was performed to explore the influences of the spatially varied land‐use conditions on the LST patterns. Results revealed that rapid urbanisation in Kunming altered the local thermal environment, particularly in increasing the LST in the zone surrounding the urban core. Remote sensing indices demonstrated that water and vegetation played an important role in mitigating the urban heat island effect, while built‐up and barren land accounted for the increase in LST. The GWR improved the goodness‐of‐fit for LST modelling and provided insights into the spatially varied relationship between LST and land‐use conditions.     

Effect of Scale on the Links between Walking and Urban Design

Studies of the relationship between walking and urban form consistently show that pedestrian‐friendly neighbourhoods encourage local walking. However, the geographic scale of measurement of the built environment for developing walkability indices and their relationship with different types of walking (e.g. for transport and recreation) has not been fully examined. In this study, objective measures of the built environment were developed at three geographic scales: suburb, census collection district, and 15 min walk neighbourhood for each participant. Walking for transport and recreation within the neighbourhood was measured using the Neighbourhood Physical Activity Questionnaire. The likelihood of walking at all (yes/no) and as recommended for health benefit (150 min per week) were assessed using logistic regression. The walkability index captured a strong positive relationship between urban form and walking for transport, but found no relationship at any scale for recreational walking. Participants walking for transport and living in high versus low walkable areas were 63% more likely to walk at the suburb scale (odds ratio 1.63; 95% confidence interval 1.22–2.18), twice as likely to walk at the census collection district scale, and nearly three times more likely to walk at the 15 min walk scale (odds ration 2.79; 95% confidence interval 2.09–3.73). The scale at which environmental data are measured influenced the strength of the relationship, showing that the neighbourhood 15 min from home was most predictive of transport walking. This has research and policy implications. Standardised scales across studies would both improve comparability of results and enhance understanding of the influences on walking.     

Gazetteer of small‐scale monuments in prehistoric Hadramawt,Yemen: a radiocarbon chronology from the RASA‐AHSD Project research 1996–2008

This paper provides a new, interpretive gazetteer and chronology of Hadramawt’s highland monuments based on results from archaeological survey and test excavations by the RASA‐AHSD (Roots of Agriculture in southern Arabia‐Arabian Human Social Dynamics) Project. With the exception of a few incidental sightings and an unpublished pipeline survey, the prehistoric record of southern Yemen’s highland plateau has been largely unknown. There are few settlements, so that understanding human landscape history must begin with the numerous small‐scale stone monuments left by mobile people. With examples representing monuments from the fifth, fourth, third and first millennia BC, the corpus of small excavations and radiocarbon dates reported here provides the first guide to the monument types of South Arabian highlands. Monument building began under more moist conditions and appears to have commemorated animal sacrifices long before commemorating mortuary rites and interment. There appears to be a temporal break of 1000 years before the widespread and varied practices of Bronze Age tomb construction, which lasted through the third millennium BC. After another break in monument construction, tombs were reused in the first millennium BC, sometimes with successive ritual visits. The data presented offer new material for the interpretation of the lives and activities of prehistoric pastoralists throughout the Holocene.     

Deterrence Theory and the Implementation of Speed Limits in the American States

Despite the ubiquitous nature of these policies, there is disagreement in the literature regarding the direction and size of the impact that speed limits have on traffic‐related fatalities. We argue in this paper that the mixed results in previous work may arise because these studies have missed an important component of the implementation of speed limit laws. More explicitly, they have failed to adequately control for the deterrent effect of enforcement and sanctions. We develop the argument that the observed impacts of speed limits will be overly large when the certainty and severity of punishment are not accounted for. We test this assertion in a cross‐sectional time series analysis of state‐level traffic fatalities from the years 1990–2006 and find that lower speeds do save a significant number of lives. Interestingly, we find that the impact is significantly overestimated for 65‐mph limits and significantly underestimated for 70‐mph limits when enforcement, penalties, and the interaction of the two are excluded. The results also suggest that fines have a rather modest impact on fatalities unless states employ a sufficient number of troopers to enforce posted limits. In addition to clarifying previous findings related to speed limit policy, therefore, the findings contribute to the general application of deterrence theory by empirically confirming that the importance of sanction severity is dependent on the perceived certainty of punishment.