First records of demersal fishes from the North Cape ‐ three kings area of New Zealand,with a record of a prespawning aggregation of ling,Genypterus blacodes (note)

Seventeen demersal fish species collected during a commercial line fishing trip off northern New Zealand are listed together with data on abundance, location, and habitat. These are the first records for the area; 15 are the most northerly records for the species and major range extensions are recorded for Centroscymnus owstoni, Deania calcea, Etmopterus lucifer, Pseudophycis barbata, and Hyperoglyphe antarctica. A prespawning aggregation of ling, Genypterus blacodes, is recorded for the first time from this region.     

H2O–CO2 solubility in mafic alkaline magma: applications to volatile sources and degassing behavior at Erebus volcano, Antarctica

We present new equilibrium mixed-volatile (H₂O–CO₂) solubility data for a phonotephrite from Erebus volcano, Antarctica. H₂O–CO₂-saturated experiments were conducted at 400–700 MPa, 1,190 °C, and ~NNO + 1 in non-end-loaded piston cylinders. Equilibrium H₂O–CO₂ fluid compositions were determined using low-temperature vacuum manometry, and the volatile and major element compositions of the glassy run products were determined by Fourier transform infrared spectroscopy and electron microprobe. Results show that the phonotephrite used in this study will dissolve ~0.8 wt% CO₂ at 700 MPa and a fluid composition of $ X_{{{\text{H}}_{ 2} {\text{O}}}} $ ~0.4, in agreement with previous experimental studies on mafic alkaline rocks. Furthermore, the dissolution of CO₂ at moderate to high $ X_{{{\text{H}}_{ 2} {\text{O}}}}^{\text{fluid}} $ in our experiments exceeds that predicted using lower-pressure experiments on similar melts from the literature, suggesting a departure from Henrian behavior of volatiles in the melt at pressures above 400 MPa. With these data, we place new constraints on the modeling of Erebus melt inclusion and gas emission data and thus the interpretation of its magma plumbing system and the contributions of primitive magmas to passive and explosive degassing from the Erebus phonolite lava lake.     

Situating the geographies of injustice in democratic theory

Post-Marxist and poststructuralist ontologies of the political have been important reference points for recent discussions of democracy in critical human geography and related fields. This paper considers the conceptual placement of contestation in a strand of democratic theory often denigrated by these approaches, namely theories of deliberative democracy informed by post-Habermasian Critical Theory. It is argued that this concern with contestation derives from a focus on the relationships between different rationalities of action. It is proposed that this tradition of thought informs a distinctively phenomenological approach to understanding the situations out of which democratic energies emerge. In elaborating on this phenomenological understanding of the emergence of political space, the paper proceeds in three stages. First, it is argued that the strong affinities between ontological conceptualisations of ‘the political’ and the ontological register of canonical spatial theory squeezes out any serious consideration of the plural rationalities of ordinary political action. Second, debates between deliberative and agonistic theorists of democracy are relocated away from questions of ontology. These are centred instead on disputed understandings of ‘normativity’. This move opens up conceptual space for the analysis of phenomenologies of injustice. Third, using the example of debates about transnational democracy in which critical theorists of deliberative democracy explicitly address the reconfigurations of the space of ‘the political’, it is argued that this Critical Theory tradition can contribute to a distinctively ‘topological’ sense of political space which follows from thinking of political action as emerging from worldly situations of injustice. In bringing into focus this phenomenological approach to political action, the paper has lessons for both geographers and political theorists. Rather than continuing to resort to a priori models of what is properly political or authentically democratic, geographers would do well to acknowledge the ordinary dynamics and disappointments which shape political action. On the other hand, political theorists might do well to acknowledge the limits of the ‘methodological globalism’ that characterises so much recent work on the re-scaling of democracy.     

印支地体泥盆纪牙形石、放射虫和竹节石组合

Devonian faunas including conodonts, radiolari-ans, tentaculitids and other important fossils have re-cently been found at several localities in the Indochina Terrane. These faunas are biostratigraphically and tectonically important.     

New insight into the factors leading to the 1998 flank collapse and lahar disaster at Casita volcano,Nicaragua

During unusually high rainfall associated with Hurricane Mitch in 1998, a flank collapse leading to a disastrous lahar occurred at Casita volcano, Nicaragua. The lack of a similar failure during a rainfall event of comparable magnitude in 1982 (Tropical Storm Alleta) suggests that additional factors influenced the 1998 collapse. We have investigated the potential contribution of erosional flank undercutting, seismic activity and anthropogenic land-cover change at the collapse site. Except for seismic events prior to Mitch, which may have increased flank instability, none of these factors appears significant. Instead, for failure to occur, the following conditions were required: (1) highly fractured slope material allowing deep and rapid infiltration of meteoric water, (2) a less permeable underlying layer to obstruct drainage, (3) strong, continuous antecedent rainfall to build up high pore-water pressure, and (4) episodic, high-intensity precipitation during Mitch to generate recurrent pressure waves. Prerequisite (1) was provided by edifice-wide deformation towards the south-east, seismic activity and proximity to a prominent fault, and local subsidence. Condition (2) was met by clay-rich layers resulting from hydrothermal alteration. More than 1,900 mm of rain fell in the 6 months prior to Mitch without significant interruption, while intense episodic precipitation occurred during the hurricane, satisfying conditions (3) and (4), respectively. The main difference with Alleta was that it occurred at the beginning of the rainy season and, therefore, without sufficient antecedent rainfall. Anthropogenic activity, including land-cover change, did not affect slope stability (i.e. the hazard). However, vulnerability was generated when two towns were established in the lowlands south of Casita, on top of previous lahar deposits. It was greatly increased when approximately 4 km of forest between the collapse site and the towns were cleared, paving the way for a largely unobstructed debris flow. Deforestation also facilitated erosion along the flanks to provide about 78% of the material contained in the lahar when it destroyed the towns, killing more than 2,500 people.     

Formation,Evolution, and Dissipation of Coastal Sea Fog

Evolution of sea fog has been investigated using three-dimensional Mesoscale Model 5 (MM5) simulations. The study focused on widespread fog-cloud layers advected along the California coastal waters during 14–16 April 1999. According to analysis of the simulated trajectories, the intensity of air mass modification during this advection significantly depended on whether there were clouds along the trajectories and whether the modification took place over the land or ocean. The air mass, with its trajectory endpoint in the area where the fog was observed and simulated, gradually cooled despite the gradual increase in sea-surface temperature along the trajectory. Modelling results identified cloud-top cooling as a major determinant of marine-layer cooling and turbulence generation along the trajectories. Scale analysis showed that the radiative cooling term in the thermodynamic equation overpowered surface sensible and latent heat fluxes, and entrainment terms in cases of the transformation of marine clouds along the trajectories. Transformation of air masses along the trajectories without clouds and associated cloud-top cooling led to fog-free conditions at the endpoints of the trajectories over the ocean. The final impact on cloud-fog transition was determined by the interaction of synoptic and boundary-layer processes. Dissipation of sea fog was a consequence of a complex interplay between advection, synoptic evolution, and development of local circulations. Movement of the high-pressure system over land induced weakening of the along-shore advection and synoptic-pressure gradients, and allowed development of offshore flows that facilitated fog dissipation.