A New Basal Neoceratopsian Dinosaur from the Middle Cretaceous of Jilin Province, China

A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province, China). Helioceratops differs from other basal neoceratopsiaus with its deep dentary ramus, its steeply-inclined ventral predentary facet, its heterogeneous dentary crowns, and by the denticles and secondary ridges asymmetrically distributed on either side of the primary ridge on its dentary teeth. Along with Auroraceratops and Yamaceratops, Helioceratops represents one of the most derived non-coronosaurian neoceratopsians. The palaeogeographical distribution of basal neoceratopsians appears limited to northern China and southern Mongolia in the current state of our knowledge. It is therefore probable that this region constituted the birthplace for more advanced, Late Cretaceous Coronosauria.     

Assessment of Holocene surface hydrological connections for the Ounianga lake catchment zone (Chad)

A hydrological perspective to the recent sedimentary analysis conducted at Lake Yoa (Ounianga region, NE Chad) is proposed. The complex hydrological and hydrogeological situation alters the climatic stress. The potential paleo-water network and lake levels have been computed based on SRTM elevation information and ArcGis software. Results show that Lake Yoa is situated in a favorable location, and in addition to continuous input from the Nubian Sandstone Aquifer System (NSAS), it could benefit from river input from distant recharge areas, including the Tibesti Mountains and a large catchment area in the Erdis. Water budgets for 6000 cal yr BP reconstructed conditions show that the maximum lake level (40 m above its present level) was probably maintained relatively easily by surface and subsurface water.     

A gap in the North American Central Plains conductivity anomaly

The palaeotectonic models of the North American continent have been deeply influenced by the concept of a North American Central Plains conductivity anomaly (NACPCA) which was postulated as a result of large area, wide-spaced, array studies, using the Magnetic Deep Sounding (MDS) method.

A recent closely spaced magnetotelluric (MT) survey across this proposed anomaly near the Canadian-U.S. boundary by Jones and Savage (1986) failed to detect the NACPCA at the location suggested by the MDS. However, this survey did verify a conductivity anomaly discovered by Rankin and Kao (1979) and a new anomaly 75 km east of NACPCA. Our present study verifies this latter anomaly and quantitative results are presented. The striking isotropy in apparent resistivity does not prevent the interpretation of anomalous resistivity distributions. This is discussed in the text.

The failure of the MDS array studies to detect our anomaly is readily explainable by the wide station spacing; however, the failure of the MT survey to detect the NACPCA leads us to the conclusion that it may not be a continuous feature.     

Structural style and evolution of the Gulf of Lion Oligo-Miocene rifting: role of the Pyrenean orogeny

The Gulf of Lion margin results from the Cligo-Aquitanian rifting and Burdigalian crustal separation between continental Europe and Corsica-Sardinia. Immediately before the onset of extension, the area of the Gulf of Lion was affected by the Pyrenean orogeny which controlled the structural style of the evolving margin. During extension, the foreland of the Pyrenean orogen was affected by extensional thin-skinned tectonics. The décollement level ramped down into the basement, in areas where the latter was thickened during orogeny. In this intermediate part, the margin was extended by several crustal-scale low-angle faults, which generated small amounts of syn-rift sedimentation compared with the accumulation of post-rift sediments. However, more than 4 km of syn-rift sediments were deposited in the Camargue basin, which is located at the transition between thin- and thick-skinned extensional systems. Kinematic restorations and stratigraphy suggest a pre-rift surface elevation above sea-level of at least 1 km in the intermediate part of the margin, which is in agreement with reduced syn-rift sedimentation. The slope area extends seaward of the North Pyrenean Fault, a terrane boundary inherited from the Pyrenean collision. This part of the margin was stretched by seaward dipping low-angle block tilting of the upper crust, and antithetic lower crustal and sub-crustal detachment. The lithospheric structures inherited from the Pyrenean orogeny exerted a strong control on the kinematics of the rifting and on the distribution and history of subsidence. Such parameters need to be integrated in the definition of pre-rift initial conditions in future basin-modelling of the Gulf of Lion.     

Development of an automated method for continuous detection and quantification of cliff erosion events

Three intrusive systems of detection and quantification of coastal erosion events (using thermocouples and thermal pins) were developed and tested from 2005 to 2008 in different regions of the Gulf and maritime estuary of the St Lawrence (Quebec, Canada). The 3‐m‐long thermal pins inserted inside unconsolidated deposits allow the monitoring of erosion for a time period sometimes extending over several seasons. The thermocouple or thermocable method allows not only the instrumentation of unconsolidated deposits but also of rocky and cohesive substrate to a depth of 85 cm. An autonomous microclimatic station located near the experimental sites simultaneously samples temperature parameters, precipitation, snow cover, wind speed and direction as well as global radiation. The differential analysis of cliff thermal regime performed simultaneously with an analysis of air temperature makes it possible to determine the activation periods of coastal erosion processes. The results also make it possible to establish with precision the actual influence of rapid variations of certain climatic and microclimatic parameters (radiation, presence of snow cover, precipitation, etc.) on the physical state of surfaces and also on the activation of certain physical processes connected to coastal erosion events. The automated thermal erosion pin system (ATEPS) allows high temporal resolution (i.e. continuous) monitoring, enabling a real coupling of coastal erosion rates and climatic parameters. Preliminary results with the ATEPS system indicate that mild winter temperature and direct solar radiation are significant factors controlling cliff retreat rates. Moreover, the melting of segregation ice during the spring thaw contributed for more than 70% of cliff retreat against only 30% for frost shattering. Copyright © 2010 John Wiley & Sons, Ltd.     

Stone runs in the Falkland Islands: Periglacial or tropical?

“Stone runs” is the Falklands vernacular term for openwork boulder accumulations, which include extensive blockstreams like the famous Darwin “stone-river” and associated features such as stone stripes. Since the early 20th century, they have been interpreted as the product of a suite of periglacial processes, including frost-wedging, gelifluction, frost heave, frost-sorting and snowmelt runoff. Following a literature review, the results of recent field investigations of the valley-floor blockstreams of East Falkland are presented. Access to the internal structure of these forms provides evidence for the existence of a three-fold profile, with clear vertical size gradation presenting striking similarities with an inverted weathering profile. Micromorphological analyses, SEM, XRD, thin sections and grain-size analyses lead to the hypothesis of an alternative model of stone run formation. It is suggested that the material forming the stone run profile lato sensu (including the superficial pavement) is not of periglacial origin, but derives directly from the stripping and accumulation downslope of a regolith, possibly Tertiary in age and formed under subtropical or temperate conditions. The valley-floor stone runs should, therefore, be considered as complex polygenetic landforms that may have formed according to a six-stage scenario, including in situ chemical weathering, regolith stripping by mass movements, soil formation, further regolith stripping, downslope accumulation and matrix washing-out (all phases possibly achieved by the Early Quaternary). Periglacial reworking of the stone run material would have operated at a “final” stage, i.e. during Quaternary cold stages, with boulder bioweathering and limonite-staining operating during the temperate intervals including the present one. The suggested antiquity of the Falklands blockstreams is in accordance with Caine's pioneer interpretation of Tasmania blockfields and with recent analyses and cosmogenic datings of blockfields from Scandinavia and North America.     

Stretching lineation and transport direction in the Ibero-Armorican arc during the siluro-devonian collision

Abstract

Large structures, lineations, foliations and sense of shear criteria are examined on the scale of the whole Ibero-Armorican Arc. Four sections (Galicia, Brittany-Vendée, Limousin and Eastern Massif Central) exemplify the major thrust sheets observed around the Arc. Stretching lineations are contemporaneous with the siluro-devonian metamorphism and are either transverse, oblique or parallel to the collision zone. A kinematic analysis shows that these lineations have resulted from a dominanüy transverse shear deformation which was followed by, or combined with, a longitudinal shear direction. On the scale of the entire Arc, this variation in the shear direction is interpreted as resulting from an early head on thrusting relative movement evolving to large scale movements parallel to the plate boundaries. Experiments with sand-silicone models support a model which generates the Arc by interaction between a transform sinistral direction, and a converning zone at a high angle to the transform direction.     

The Life Cycle of Caravan Parks in Australia: the case of northern New South Wales

The caravan park sub-sector of the Australian tourism accommodation industry provides at least half of the national tourism bed capacity, and in 2009 generated over A$1.1 billion in annual takings. However, the number of parks and park capacity is in decline nationally while both international and domestic demand for the drive-tourism experience is growing. This sets a trend towards an accommodation facilities shortage for the caravanning sector and exposes its vulnerability. This paper uses a case study of caravan parks in the Tweed Shire, New South Wales, Australia, to examine the life-cycle pattern of these parks as a discrete unit of tourist area development and to consider the sector's future. The sector's history is framed within Butler's (Canadian Geographer 24(1): 5–12 (1980)) concept of the tourist area life cycle (TALC). The historical data demonstrate the urban and market change that has occurred around and within caravan parks of this coastal region over almost two centuries. The pattern of caravan park development and evolution conformed to the involvement, exploration, development, consolidation and stagnation stages of the TALC. In 2011, caravan parks in the Tweed region were at a critical tipping point with potential for either decline or rejuvenation.     

Assessing temporary carbon sequestration and storage projects through land use, land-use change and forestry: comparison of dynamic life cycle assessment with ton-year approaches

In order to properly assess the climate impact of temporary carbon sequestration and storage projects through land-use, land-use change and forestry (LULUCF), it is important to consider their temporal aspect. Dynamic life cycle assessment (dynamic LCA) was developed to account for time while assessing the potential impact of life cycle greenhouse gases (GHG) emissions. In this paper, the dynamic LCA approach is applied to a temporary carbon sequestration project through afforestation, and the results are compared with those of the two principal ton-year approaches: the Moura-Costa and the Lashof methods. The dynamic LCA covers different scenarios, which are distinguished by the assumptions regarding what happens at the end of the sequestration period. In order to ascertain the degree of compensation of an emission through a LULUCF project, the ratio of the cumulative impact of the project to the cumulative impact of a baseline GHG emission is calculated over time. This ratio tends to 1 when assuming that, after the end of the sequestration project period, the forest is maintained indefinitely. Conversely, the ratio tends to much lower values in scenarios where part of the carbon is released back to the atmosphere due to e.g. fire or forest exploitation. The comparison of dynamic LCA with the ton-year approaches shows that it is a more flexible approach as it allows the consideration of every life cycle stage of the project and it gives decision makers the opportunity to test the sensitivity of the results to the choice of different time horizons.