Shipboard trials of an ozone-based ballast water treatment system

Legislation introduced by the United Nations International Maritime Organization (IMO) has focused primarily on standards defining successful treatments designed to remove invasive species entrained in ballast water. An earlier shipboard study found that ozone introduced into salt water ballast resulted in the formation of bromine compounds, measured as total residual oxidants (TRO) that were toxic to both bacteria and plankton. However, the diffuser system employed to deliver ozone to the ballast water tanks resulted in patchiness in TRO distribution and toxicity to entrained organisms. In this follow-up study, the shipboard diffuser system was replaced by a single Venturi-type injection system designed to deliver a more homogeneous biocide distribution. Within-tank variability in TRO levels and associated toxicity to zooplankton, phytoplankton and marine bacteria was measured via a matrix of tubes deployed to sample different locations in treated and untreated (control) tanks. Three trials were conducted aboard the oil tanker S/T Prince William Sound in the Strait of Juan de Fuca off Port Angeles, Washington State, USA, between June and December 2007. Mortalities of plankton and bacteria and oxidant concentrations were recorded for treated and untreated ballast water up to 3 days following treatment, and residual toxicity beyond this period was measured by bioassay of standard test organisms. Results indicated uniform compliance with current IMO standards, but only partial compliance with other existing and pending ballast water legislation.     

Early phases of Caledonian deformation in the Dalradian of the Ballachulish district,Argyll

Two early phases of deformation preceded the development of the major NE-SW-trending folds, including the Appin Fold. The earliest recognized structures include small folds, lineations and inclusion trails in garnet porphyroblasts. The dominant schistosity and mineral lineation was developed during the second phase of deformation, associated with the formation of similar folds and tectonic banding, under garnet grade conditions over much of the area. The later-formed major folds are associated with low grade retrogressive metamorphism and crenulation and fracture cleavage formation. These folds are concentric folds and have associated tectonic slides producing low grade cataclastic schists. On the basis of fold style and sequence and metamorphic grade there is a great similarity between the structures in the Dalradian rocks of the Ballappel Foundation and those of the Iltay Nappe.     

Application of the patient rule induction method to detect hydrologic model behavioural parameters and quantify uncertainty

Finding an operational parameter vector is always challenging in the application of hydrologic models, with over‐parameterization and limited information from observations leading to uncertainty about the best parameter vectors. Thus, it is beneficial to find every possible behavioural parameter vector. This paper presents a new methodology, called the patient rule induction method for parameter estimation (PRIM‐PE), to define where the behavioural parameter vectors are located in the parameter space. The PRIM‐PE was used to discover all regions of the parameter space containing an acceptable model behaviour. This algorithm consists of an initial sampling procedure to generate a parameter sample that sufficiently represents the response surface with a uniform distribution within the “good‐enough” region (i.e., performance better than a predefined threshold) and a rule induction component (PRIM), which is then used to define regions in the parameter space in which the acceptable parameter vectors are located. To investigate its ability in different situations, the methodology is evaluated using four test problems. The PRIM‐PE sampling procedure was also compared against a Markov chain Monte Carlo sampler known as the differential evolution adaptive Metropolis (DREAM_ZS) algorithm. Finally, a spatially distributed hydrological model calibration problem with two settings (a three‐parameter calibration problem and a 23‐parameter calibration problem) was solved using the PRIM‐PE algorithm. The results show that the PRIM‐PE method captured the good‐enough region in the parameter space successfully using 8 and 107 boxes for the three‐parameter and 23‐parameter problems, respectively. This good‐enough region can be used in a global sensitivity analysis to provide a broad range of parameter vectors that produce acceptable model performance. Moreover, for a specific objective function and model structure, the size of the boxes can be used as a measure of equifinality.     

CuNi-VTiFe复合型矿化镁铁-超镁铁杂岩体岩相学及岩石地球化学特征:以新疆北部为例

铜镍硫化物矿床和钒钛磁铁矿矿床是镁铁-超镁铁杂岩重要的矿床类型,但二者共生的情况在国内还不多见。新疆北部这类铜镍-钒钛铁复合型矿化岩体较为发育,目前已发现有香山、牛毛泉、土墩南和哈拉达拉等4个岩体属于此类。它们的成岩时代多集中在早二叠世,出露面积在2.8～22km~2,介于通道型铜镍矿化小岩体和大型层状岩体之间,韵律构造发育;岩石组合为超基性-基性-中性岩类,以出现浅色的闪长岩或淡色辉长岩为特点,岩石中金属矿物氧化物(钛铁矿、磁铁矿)和硫化物(黄铁矿、磁黄铁矿、黄铜矿,有时有镍黄铁矿)共存和共生;含矿岩石组合和岩石化学特征与典型铜镍硫化物矿床和钒钛磁铁矿矿床相比,具有重叠和过渡特征;稀土和微量元素特征反映出杂岩体不同岩石类型可能具有相同或相似岩浆来源,是经过强烈分异和演化的产物。新疆北部这类复合型矿化,与北疆地区典型铜镍矿床和典型钒钛磁铁矿矿床,共同构成了新疆北部后碰撞幔源岩浆矿床成矿谱系。     

Application of seismic and sequence stratigraphic concepts to a lava‐fed delta system in the Faroe‐Shetland Basin,UK and Faroes

Detailed seismic stratigraphic analysis of 2D seismic data over the Faroe‐Shetland Escarpment has identified 13 seismic reflection units that record lava‐fed delta deposition during discrete periods of volcanism. Deposition was dominated by progradation, during which the time shoreline migrated a maximum distance of ～44 km in an ESE direction. Localised collapse of the delta front followed the end of progradation, as a decrease in volcanic activity left the delta unstable. Comparison with modern lava‐fed delta systems on Hawaii suggests that syn‐volcanic subsidence is a potential mechanism for apparent relative sea level rise and creation of new accommodation space during lava‐fed delta deposition. After the main phase of progradation, retrogradation of the delta occurred during a basinwide syn‐volcanic relative sea level rise where the shoreline migrated a maximum distance of ～75 km in a NNW direction. This rise in relative sea level was of the order of 175–200 m, and was followed by the progradation of smaller, perched lava‐fed deltas into the newly created accommodation space. Active delta deposition and the emplacement of lava flows feeding the delta front lasted ～2600 years, although the total duration of the lava‐fed delta system, including pauses between eruptions, may have been much longer.     

IPHAS discoveries of young stars towards Cyg OB2 and its southern periphery

We report on the discovery of over 50 strong Hα emitting objects towards the large OB association Cyg OB2 and the H  ii region DR 15 on its southern periphery. This was achieved using the INT Photometric Hα Survey of the Northern Galactic Plane (IPHAS), combined with follow-up spectroscopy using the MMT multi-object spectrometer HectoSpec. We present optical spectra, supplemented with optical r ',  i ' and H α photometry from IPHAS, and near-infrared J ,  H and K photometry from Two Micron All Sky Survey. The position of the objects in the ( J − H ) versus ( H − K ) diagram strongly suggests most of them are young. Many show Ca  ii infrared triplet emission indicating that they are in a pre-main-sequence phase of evolution of T Tauri and Herbig Ae nature. Among these, we have uncovered pronounced clustering of T Tauri stars roughly a degree south of the centre of Cyg OB2, in an arc close to the H  ii region DR 15, and the radio ring nebula G79.29+0.46, for which we discuss its candidacy as a luminous blue variable. The emission-line objects towards Cyg OB2 itself could be the brightest most prominent component of a population of lower mass pre-main-sequence stars that has yet to be uncovered. Finally, we discuss the nature of the ongoing star formation in Cyg OB2 and the possibility that the central OB stars have triggered star formation in the periphery.     

Ammonites

Ammonites were amongst the most successful marine animals during the Mesozoic. They evolved to fill a large variety of ecological niches across a wide spectrum of open‐ocean and marine shelf environments. Despite the fact that hundreds of thousands have been collected in the last 200 years and are available for study in museum collections, the biology of ammonites—how they lived—is very difficult to understand. They lived such exotic and strange lives comparable with no group alive today, and seemed to break all the rules of Darwinian biology. Their importance in stratigraphy is due to their rapid evolution, which gave rise to a more refined zonal scheme than is possible with any other group of fossil, making the need to understand ammonite biology of more than academic interest.     

How much physical complexity is needed to model flood inundation?

Two‐dimensional flood inundation models are widely used tools for flood hazard mapping and an essential component of statutory flood risk management guidelines in many countries. Yet, we still do not know how much physical complexity a flood inundation model needs for a given problem. Here, three two‐dimensional explicit hydraulic models, which can be broadly defined as simulating diffusive, inertial or shallow water waves, have been benchmarked using test cases from a recent Environment Agency for England and Wales study, where results from industry models are also available. To ensure consistency, the three models were written in the same code and share subroutines for all but the momentum (flow) and time‐stepping calculations. The diffusive type model required much longer simulation times than the other models, whilst the inertia model was the quickest. For flows that vary gradually in time, differences in simulated velocities and depths due to physical complexity were within 10% of the simulations from a range of industry models. Therefore, for flows that vary gradually in time, it appears unnecessary to solve the full two‐dimensional shallow water equations. As expected, however, the simpler models were unable to simulate supercritical flows accurately. Finally, implications of the results for future model benchmarking studies are discussed in light of a number of subtle factors that were found to cause significant differences in simulations relative to the choice of model. Copyright © 2011 John Wiley & Sons, Ltd.     

Soil water content in southern England derived from a cosmic‐ray soil moisture observing system – COSMOS‐UK

Cosmic‐ray soil moisture sensors have the advantage of a large measurement footprint (approximately 700 m in diameter) and are able to operate continuously to provide area‐averaged near‐surface (top 10–20 cm) volumetric soil moisture content at the field scale. This paper presents the application of this technique at four sites in southern England over almost 3 years. Results show the soil moisture response to contrasting climatic conditions during 2011–2014 and are the first such field‐scale measurements made in the UK. These four sites are prototype stations for a UK COsmic‐ray Soil Moisture Observing System, and particular consideration is given to sensor operating conditions in the UK. Comparison of these soil water content observations with the Joint UK Land Environment Simulator 10‐cm soil moisture layer shows that these data can be used to test and diagnose model performance and indicate the potential for assimilation of these data into hydro‐meteorological models. The application of these large‐area soil water content measurements to evaluate remotely sensed soil moisture products is also demonstrated. Numerous applications and the future development of a national COsmic‐ray Soil Moisture Observing System network are discussed. Copyright © 2016 John Wiley & Sons, Ltd.