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Oxygen isotope-inferred ages as old as the Jurassic have been derived from weathered monzogranite underlying the folded Mount Augustus Sandstone, which forms the massive anticlinal Burringurrah (or Mount Augustus) inselberg, in the Gascoyne district of Western Australia. This large inselberg stands ~700 m above the surrounding duricrusted Neogene Gascoyne planation surface at ~400 m. The 1150 m thick Mount Augustus Sandstone (c. 1620 Ma), buried by some 10 km of rock of the Edmund and Collier Groups, underwent folding during the Edmundian Orogeny (1030–950 Ma). Abundant Permian glacial deposits throughout western and southern Australia suggest that the landscape was extensively impacted by a continental ice mass during the Gondwanan Permian glaciation, and which provides a maximum age for most recorded chemical weathering profiles within Australia. Nine samples of kaolinite were collected from a 30 m deep exposure of weathered monzogranite cropping out in the core of the anticline beneath the overlying Mount Augustus Sandstone within the topographic amphitheatre of ‘The Pound’. Four samples from the profile were analysed, revealing two ages of weathering. The higher samples immediately below the unconformably overlying boulder ferricrete (δ18OVSMOW values of +12.0 and +14.0‰) imply a Jurassic to early Cretaceous weathering age, while the lower samples (δ18OVSMOW values of +17.6 and +18.3‰) are indicative of a Neogene age. These results suggest downward ‘younging’ of the profile consistent with a top-down advancing weathering front that developed after uncapping of the anticlinal inselberg and exposure of the underlying monzogranite to surficial chemical weathering. A long-term rate of landscape denudation of ~11 m/Ma is estimated from established geological events, rock ages and thicknesses. Dykes and quartz veins suggest that Burringurrah was still deeply buried 500 Ma ago, with the denudation rate indicating exposure of the upper surface of the Mount Augustus Sandstone by ~100 Ma. The oxygen isotope data suggest that weathering of the monzogranite beneath the Mount Augustus Sandstone occurred during Jurassic to early Cretaceous times (~200 to 100 Ma), ages broadly coincident with those derived from the application of denudation rates. This suggests that Burringurrah initially developed as an inselberg prior to at least the past 100 Ma. The younger ages from lower parts of the profile suggest that weathering continued into the Neogene/Quaternary (23 Ma to present), during which time the surrounding, now dissected, planation surface was also weathered.

This paper contributes to understanding the physical and economic effects of salinity diffusion and planning for appropriate adaptation for managing the Sundarbans in a changing climate, with a focus on the West Bengal portion of the tidal-wetland forest delta. A five-step analysis, using high-resolution spatial assessments, was conducted to get a broader picture of the migration of mangrove species with progressive aquatic salinization in a changing climate. A current (2015) basemap, with overlays of salinity tolerance for various mangrove species, and projected location-specific aquatic salinity for 2050 were used to predict the impacts of salinization on mangrove species by 2050. The results indicate patterns of gains and losses, with dominance of salt-tolerant species at the expense of freshwater species. Overall, the impact of salinity-induced mangrove migration will have an adverse effect on the flow of ecosystem services, ultimately impacting the livelihood options of poor households. Resources should be directed to developing alternative livelihoods for mangrove-dependent households. In addition, efforts are needed to develop sustainable policies that incorporate rising salinity, changes in mangrove dynamics, and the welfare impacts on poor communities.

Recurrent cyclonic storms in the Bay of Bengal inflict massive losses on the coastal regions of Bangladesh and India. Information on occurrences and severities of cyclones is necessary for understanding household and community responses to cyclone risks. This paper constructs a georeferenced panel database that can be used to obtain such information for Bangladesh, West Bengal, and Odisha. Cyclone strike locations and impact zones are analyzed for several historical periods between 1877 and 2016. The findings indicate that although the median location has shifted eastward, there is a marked variability in location, especially after 1960. Impacts also have varied considerably within and across zones over time, with the highest-impact zones in northern Odisha and the Sundarbans region of West Bengal. The pronounced spatial and temporal variation in cyclone impacts will provide robust controls for comparative research on household and community adaptation to cyclones in the study region. The methodology developed in the paper is general and could be expanded to an arbitrarily large set of coastal locations.

This paper investigates possible impacts of climate change on the poor communities of the Bangladesh Sundarbans via changes in aquatic salinity and mangrove species. The implications for poor communities are assessed by computing changes in high-value mangrove species for the five sub-districts in the Sundarbans. The results of the impact analysis indicate highly varied patterns of gain and loss across the five sub-districts. Overall, however, the results indicate that salinity-induced mangrove migration will have a strongly regressive impact on the value of timber stocks because of the loss of the highest value timber of Heretiera fomes. In addition, augmented potential for honey production is likely to increase conflicts between humans and wildlife in the region.

Total organic carbon (TOC), total nitrogen (TN) and their δ 13 C and δ 15 N values were determined from 110 sediment samples from the Ayeyarwady (Irrawaddy) continental shelf, northern Andaman Sea to decipher the concentration and source of organic matter. Comparatively higher TOC and TN concentrations are found in the inner-shelf mud belt, and on the continental slope sediments, whereas the outer-shelf sediments, composed mostly of relict sands, are low in TOC. The TOC contents are positively correlated with the abundance of fine-grained sediments. The TOC:TN ratios and δ 13 C and δ 15 N values show low variability within the modern inner-shelf mud belt and Gulf of Martaban, indicating similar source. The TOC:TN ratios are mostly between 6 and 8 in the inner-shelf mud belt and these values are similar to the suspended sediments in the Ayeyarwady and Salween rivers. The δ 13 C values of organic matter increase from − 25‰ in the Gulf of Martaban to about − 22‰ in the slope regions indicating decreasing terrestrial input away from the coast. The δ 15 N values on the Ayeyarwady shelf are rather low (+ 3.3 to + 4.8‰), especially off the mouths of the Ayeyarwady River mouths, reflecting greater influence of freshwater and terrigenous sediment discharge. A simple two end-member carbon mixing model applied to the Ayeyarwady shelf region indicates that terrigenous sources contribute more than 70% of the organic carbon in the modern mud belt in the inner shelf and Gulf of Martaban. Terrigenous organic carbon percentages reduce gradually offshore, reducing to less than 60% near the continental shelf edge. A strong terrigenous signal is preserved in the inner shelf and Gulf of Martaban sediments probably because organic matter from the source region is not subject to intensive processing and replacement in the floodplains and deltaic regions as well as rapid burial at sea.

Road construction has often been viewed as the precursor to deforestation, especially in tropical forests. Traditional responses to such threats have been reactive, with attempts to mitigate impacts through physical measures, or the establishment of protected areas. These approaches often have not been entirely successful, especially in areas where economic potential is significant. This paper seeks to mitigate such conflicts by proposing a proactive approach to development planning and environmental policy. It develops a high-resolution spatial model of road improvement impacts that includes ecological risks and the economics of forest clearing. The approach is implemented by estimating the potential impact of road upgrading on forest clearing and biodiversity in eight Congo Basin countries. The paper demonstrates how the detailed analysis can identify areas of high ecological priority as well as areas at high risk of forest loss. The paper contributes to several aspects of the literature. First, it provides the most recent and reliable estimates of the drivers of deforestation in the Congo Basin, with the latest high-resolution satellite data on forest cover changes. Second, it presents novel estimates of biodiversity threats by creating an index that combines and synthesizes several measures of biodiversity loss and impacts. It then develops an empirical framework for estimating the ecological impacts of road improvement. Finally, the paper illustrates how the empirical framework can be used to preempt impacts and avoid potential ecological damage.

A significant uncertainty exists as to whether δ13C values in charcoal meaningfully represent the stable isotopic content of the original material, with studies suggesting variable responses to both natural and laboratory heating. An extensive study was undertaken using fully homogenised samples of wood taken from Eucalyptus spp., Quercus robur and Pinus radiata. The results demonstrate that the duration of heating had no tangible effect on the final composition of the charred material, with the δ13C and carbon content of wood fixed after 30 min of heating. Furthermore, all three wood types become progressively depleted in 13C with increasing temperature. The results demonstrate that even at temperatures commonly reached in natural fires (

The Jervis Bay area offers a diversity of landforms that do not fit within contemporary views of coastal evolution. Field evidence indicates that catastrophic tsunami have had a significant impact on the coast and its hinterland both within and outside the embayment. Runup has overtopped cliffs 80 m above sea level and deposited chevron-shaped ridges to elevations of 130 m on the southern headland. Boulders, up to 6 m in diameter, have been deposited in an imbricated fashion against cliffs, on clifftops, and along shoreline ramps. Bed-form features and the size of transported material indicate flow depths up to 10 m and velocities around 8 m s-1. While significant Pleistocene material has been swept onto the coastline, mainly in the form of barriers, radiocarbon dating indicates that tsunami have occurred repetitively throughout the Holocene. The most recent event occurred just before European settlement over 200 years ago. [Key words: barrier beaches, coastal geomorphology, tsunami, Jervis Bay, Australia.]

The present research examines the possibility that 'freezing' or slowing-down the rate at which threats can advance and thereby blocking a sense of looming vulnerability can reduce fears of contamination and avoidance behavior among individuals with obsessional symptoms. Mental imagery was used to reduce the rate at which threat can advance by means of instructions to imagine that contamination was 'frozen' in place and unable to move. Measures included self-reports of anxiety and worry, and indirect assessments of fear and avoidance behavior. A parallel mental imagery condition was used to examine the possibility that accentuating the spread or contamination, or its 'looming', would in turn accentuate fear and avoidance. The results, particularly of the more unobtrusive measures, indicated that freeze imagery reduced fear and avoidance for the relatively obsessional participants. In addition, support was found that it reduced fear for participants with relatively higher levels of imagination. However, the freeze imagery paradoxically seemed to sensitize the non-obsessional participants to possibilities of contamination they had not previously considered, and thus increased their fear. The results provide support for the looming vulnerability model of anxiety and suggest applications to treatment.

The development of methods of using computers for calculations in the early fifties at Cambridge and Illinois Universities. They are the recollections of a participant.

The Gulf of Carpentaria is an epicontinental sea (maximum depth 70 m) between Australia and New Guinea, bordered to the east by Torres Strait (currently 12 m deep) and to the west by the Arafura Sill (53 m below present sea level). Throughout the Quaternary, during times of low sea-level, the Gulf was separated from the open waters of the Indian and Pacific Oceans, forming Lake Carpentaria, an isolation basin, perched above contemporaneous sea-level with outlet channels to the Arafura Sea. A preliminary interpretation is presented of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria. The longest core (approx. 15 m) spans the past 130 ka and includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 ka when sea-level repeatedly breached and withdrew from Gulf/Lake Carpentaria. Evidence from biotic remains (foraminifers, ostracods, pollen), sedimentology and geochemistry clearly identifies a final marine transgression at about 9.7 ka (radiocarbon years). Before this transgression, Lake Carpentaria was surrounded by grassland, was near full, and may have had a surface area approaching 600 km×300 km and a depth of about 15 m. The earlier rise in sea-level which accompanied the Marine Isotopic Stage 6/5 transgression at about 130 ka is constrained by sedimentological and biotic evidence and dated by optical- and thermoluminescence and amino acid racemisation methods.

A new key distribution scheme is presented. It is based on the distinctive idea that lets each node have a set of keys of which it shares a distinct subset with every other node. This has the advantage that the numbers of keys that must be distributed and maintained are reduced by a square root factor; moreover, two nodes can start conversation with virtually no delay. Two versions of the scheme are given. Their performance and security analysis shows it is a practical solution to some key distribution problems.