Coccolithophores are single-celled, marine algae (phytoplankton), which produce elaborate calcite scales (coccoliths) that form a protective covering around their delicate cell walls. They are an important part of the modern marine ecosystem, but also have a long fossil record (nannofossils) stretching back 225 million years (Triassic). Both living and fossil coccolithophores provide valuable information about ocean environments and changing climate. The fossils also provide a simple and quick means of age-dating the rocks in which they are found. For these reasons, coccolithophores are of interest to a very wide range of scientists, including marine biologists, palaeoceanographers and geologists (stratigraphers). The effective use of coccolithophores is dependent upon the availability of up to date and reliable information concerning their classification (taxonomy - which species is which, and why?), their ecology (which species live where, when and why?) and their geological history (which species lived when and where?). However, this information is frequently difficult to find because it is dispersed throughout specialist publications. In order to widen access to this crucial information, we have started work on a web resource called Nannotax (www.nannotax.org) that we hope will become the online reference source for anyone needing to obtain basic to specialist information on coccolithophores and nannofossils. Our pilot version focused on the relatively recent, Neogene, fossil record (0-23 million years ago) and has already proved popular, registering 670,000 page views and 275 registered users. We now aim to build on this, and will add more species (the older fossil record, plus all the living species), add more types of data (age, ecology and, where appropriate, biology), expand the content (glossary, guides to identification and methods of study) and bring the site to the attention of those who will most benefit from it. The end-product Nannotax website will provide a complete listing of living and fossil coccolithophore and nannofossil taxa, with short descriptions, age data, multiple illustrations, bibliographic references and original descriptions. There will be identification keys and linked pages providing information on study methods. In parallel, we will provide hands-on training in the use and potential of the system, and respond to requests from those who have 'test-driven' the system at workshops and conferences. We think that the development of this system is essential to the hydrocarbon industry and to academics and educators involved in nannoplankton research, training and learning. By removing the barriers to learning nannoplankton taxonomy, identifying specimens and obtaining accurate information about species, existing users will be enabled to expand their expertise, and we believe it will also attract a range of new users. To ensure that we are providing the right kind of information for this wide range of scientists, we have enlisted the support of project partners who represent international biologists, oceanographers, geologists and oil company stratigraphers, who will both provide us with data, and also review and comment upon our progress and product.

This proposal addresses the vital issue of prediction of multiphase flows in large diameter risers in off-shore hydrocarbon recovery. The riser is essentially a vertical or near-vertical pipe connecting the sea-bed collection pipe network (the flowlines) to a sea-surface installation, typically a floating receiving and processing vessel. In the early years of oil and gas exploration and production, the oil and gas companies selected the largest and most accessible off-shore fields to develop first. In these systems, the risers were relatively short and had modest diameters. However, as these fields are being depleted, the oil and gas companies are being forced to look further afield for replacement reserves capable of being developed economically. This, then, has led to increased interest in deeper waters, and harsher and more remote environments, most notably in the Gulf of Mexico, the Brazilian Campos basin, West of Shetlands and the Angolan Aptian basin. Many of the major deepwater developments are located in water depths exceeding 1km (e.g. Elf's Girassol at 1300m or Petrobras' Roncador at 1500-2000m). To transport the produced fluids in such systems with the available pressure driving forces has led naturally to the specification of risers of much greater diameter (typically 300 mm) than those used previously (typically 75 mm). Investments in such systems have been, and will continue to be, huge (around $35 billion up to 2005) with the riser systems accounting for around 20% of the costs. Prediction of the performance of the multiphase flow riser systems is of vital importance but, very unfortunately, available methods for such prediction are of doubtful validity. The main reason for this is that the available data and methods have been based on measurements on smaller diameter tubes (typically 25-75 mm) and on the interpretation of these measurements in terms of the flow patterns occurring in such tubes. These flow patterns are typically bubble, slug, churn and annular flows. The limited amount of data available shows that the flow patterns in larger tubes may be quite different and that, within a given flow pattern, the detailed phenomena may also be different. For instance, there are reasons to believe that slug flow of the normal type (with liquid slugs separated by Taylor bubbles of classical shape) may not exist in large pipes. Methods to predict such flows with confidence will be improved significantly by means of an integrated programme of work at three universities (Nottingham, Cranfield and Imperial College) which will involve both larger scale investigations as well as investigations into specific phenomena at a more intimate scale together with modelling studies. Large facilities at Nottingham and Cranfield will be used for experiments in which the phase distribution about the pipe cross section will be measured using novel instrumentation which can handle a range of fluids. The Cranfield tests will be at a very large diameter (250 mm) but will be confined to vertical, air/water studies with special emphasis on large bubbles behaviour. In contrast those at Nottingham will employ a slightly smaller pipe diameter (125 mm) but will use newly built facilities in which a variety of fluids can be employed to vary physical properties systematically and can utilise vertical and slightly inclined test pipes. The work to be carried out at Imperial College will be experimental and numerical. The former will focus on examining the spatio-temporal evolution of waves in churn and annular flows in annulus geometries; the latter will use interface-tracking methods to perform simulations of bubbles in two-phase flow and will also focus on the development of a computer code capable of predicting reliably the flow behaviour in large diameter pipes. This code will use as input the information distilled from the other work-packages regarding the various flow regimes along the pipe.

Subsea infrastructure networks underpin our daily lives, providing critical global communication links and supporting our demand for energy supplies. These strategically important networks are vulnerable to fast-moving seafloor flows of sediment, known as turbidity currents. Such flows have previously broken important subsea cable connections; leading to £Ms in lost financial trading and repair costs. The seafloor cable network transfers >95% of all global communications traffic. The International Cable Protection Committee (represented by partner Carter) has a vested interest in understanding the risk of turbidity currents, but there is a paucity of direct field measurements of turbidity currents. Thus, numerical models are largely based on scaled down experimental studies. Here, we show how the first deep-ocean high resolution measurements of turbidity currents can enable improved understanding of the risk posed, through calibration of numerical models for impact analysis. This will directly benefit partners Chevron and Shell, who are responsible for ensuring safe operation of multi-£M seafloor oil and gas pipelines worldwide. Loss of hydrocarbons to the environment can have severe environmental and reputational implications; hence minimising the risk of a pipe rupture is important. Improvements to modelling will be immediately taken up by partner HR Wallingford, who advise a wide range of owners and stakeholders on hazard assessment for seafloor infrastructure. We aim to address the following questions: [1] How can emerging direct monitoring technology lead to a step-change in assessment of turbidity current risk to offshore infrastructure? Until recently, there were no direct measurements of turbidity currents due to the difficulties in deployment in remote and challenging subsea environments. New advances in technology have enabled the first measurements of velocity and concentration in deep-ocean turbidity currents. Techniques developed for, and lessons learned from, the monitoring of flows at a number of sites will be transferred to industry partners. This first aim is thus to help improve how industry assesses turbidity current hazards by using the first ever direct measurements. [2] How appropriate are existing models and how should they be revised based on new field-scale calibrations? As no comparable datasets exist, this new direct monitoring provides a unique opportunity to validate, test and refine numerical models of turbidity current. We will first assess how appropriate existing flows employed by industry are at recreating real flow behaviour. We will then run variants of a depth-resolved model developed by Dorrell. The aim is to provide a modelling approach that is acceptable in terms of computational cost, and that can recreate observations from direct monitoring. Specific guidance will be provided to the partners on how models should be developed to assess impact of turbidity currents on seafloor infrastructure. [3] What impact do real-world turbidity currents have on seafloor infrastructure? We will then quantify turbidity current impact on a range of seafloor infrastructure. This is novel because it will involve the application of new models based on the first deep-sea direct monitoring data. The analysis will transform industry understanding of impacts and mitigation strategies. Deliverables will include: (i) Report outlining industry best practice for turbidity current hazard assessment; (ii) New numerical modelling approach outlined in a workshop; (iii) Summary report detailing the modelled impacts of real-world turbidity currents on a range of seafloor infrastructure, and guidance for design, mitigation measures and future data acquisition strategies. Project cost = £87.2k (at 80% FEC) over 12 months.

Our over-arching aim is to better understand the impact of powerful submarine flows, called turbidity currents, on pipelines and other seabed infrastructure used to recover oil and gas. Turbidity currents pose a serious hazard to expensive seabed installations, especially in deeper-water settings. These sediment flows are particularly hazardous because they can be exceptionally powerful (travelling at speeds of up to 20 m/s), and can flow for long distances (100s km), causing damage over vast areas of seafloor. Even weaker flows travelling at ~1-2 m/s can severely damage seafloor equipment, or break strategically important submarine telecommunication cables, while some flows have maintained speeds in excess of 5 m/s for hundreds of kilometres. This makes hazard mitigation by local re-routing of pipelines difficult. Where seafloor topography is rugged, many operators route pipelines within canyons; however, these are focal points for turbidity current activity. Mitigating against turbidity current geohazards, particularly within canyons, can have very significant cost implications for industry - additional deepwater pipeline routing costs ~ $3 million per km. Mitigation costs of $2 billion are predicted to route pipelines under the Congo Canyon, where turbidity current hazard is deemed to be high. Perhaps just as importantly, pipeline oil spills could lead to major reputational damage. Given concern over accidents to structures used to recover oil and gas, a focus on geohazards is also aligned with NERC's environmental responsibility. The most remarkable aspect of turbidity currents is how few direct measurements there are from flows, in part because they damage monitoring equipment placed on the seafloor. Several lines of evidence point to the existence of a region of high sediment concentration at the base of turbidity currents. These dense basal layers are of key important because of: (i) their location just above the bed where most submarine infrastructure is located; and (ii) they carry most momentum due to their large density. Yet, sediment concentration has never been measured directly measured in these layers. Physical experiments, numerical modeling and ancient deposits provide valuable insights into these flows; but there is a compelling need to monitor full-scale flows in action. This project is timely because it will develop innovative field-based techniques for imaging near bed flow structure and vertical changes in sediment concentration in situ. Aims: (1) Our first aim is to develop and field test a novel technique for remote sensing of dense near bed layers. (2) Our second aim is to better understand the nature of near bed dense layers. (3) Our third aim is to embed improved understanding of dense near-bed layers into numerical models used by industry to assess impact of turbidity currents on oil and gas pipelines. (4) The project will also help to establish an international centre of excellence for submarine geohazard research at the UK National Oceanography Centre. Here we propose to make direct measurements of dense basal layers that form part of the turbidity currents occuring daily during the elevated summer river discharge on the Squamish Delta, located in Howe Sound, Canada. We will use an innovative four-point mooring to hold a vessel and suspended instrumentation payload stable above an active channel system, while we observe the dense basal layer with a Chirp sub-bottom profiler. The low frequency and broad bandwidth (1.5 -13.0 kHz) Chirp source guarantees penetration through dense near-bed layers, resolving layers with ~10 cm resolution. These field observations will help to understand the fundamental character of near bed layers, and the situations in which they form.

This proposal addresses the vital issue of prediction of multiphase flows in large diameter risers in off-shore hydrocarbon recovery. The riser is essentially a vertical or near-vertical pipe connecting the sea-bed collection pipe network (the flowlines) to a sea-surface installation, typically a floating receiving and processing vessel. In the early years of oil and gas exploration and production, the oil and gas companies selected the largest and most accessible off-shore fields to develop first. In these systems, the risers were relatively short and had modest diameters. However, as these fields are being depleted, the oil and gas companies are being forced to look further afield for replacement reserves capable of being developed economically. This, then, has led to increased interest in deeper waters, and harsher and more remote environments, most notably in the Gulf of Mexico, the Brazilian Campos basin, West of Shetlands and the Angolan Aptian basin. Many of the major deepwater developments are located in water depths exceeding 1km (e.g. Elf's Girassol at 1300m or Petrobras' Roncador at 1500-2000m). To transport the produced fluids in such systems with the available pressure driving forces has led naturally to the specification of risers of much greater diameter (typically 300 mm) than those used previously (typically 75 mm). Investments in such systems have been, and will continue to be, huge (around $35 billion up to 2005) with the riser systems accounting for around 20% of the costs. Prediction of the performance of the multiphase flow riser systems is of vital importance but, very unfortunately, available methods for such prediction are of doubtful validity. The main reason for this is that the available data and methods have been based on measurements on smaller diameter tubes (typically 25-75 mm) and on the interpretation of these measurements in terms of the flow patterns occurring in such tubes. These flow patterns are typically bubble, slug, churn and annular flows. The limited amount of data available shows that the flow patterns in larger tubes may be quite different and that, within a given flow pattern, the detailed phenomena may also be different. For instance, there are reasons to believe that slug flow of the normal type (with liquid slugs separated by Taylor bubbles of classical shape) may not exist in large pipes. Methods to predict such flows with confidence will be improved significantly by means of an integrated programme of work at three universities (Nottingham, Cranfield and Imperial College) which will involve both larger scale investigations as well as investigations into specific phenomena at a more intimate scale together with modelling studies. Large facilities at Nottingham and Cranfield will be used for experiments in which the phase distribution about the pipe cross section will be measured using novel instrumentation which can handle a range of fluids. The Cranfield tests will be at a very large diameter (250 mm) but will be confined to vertical, air/water studies with special emphasis on large bubbles behaviour. In contrast those at Nottingham will employ a slightly smaller pipe diameter (125 mm) but will use newly built facilities in which a variety of fluids can be employed to vary physical properties systematically and can utilise vertical and slightly inclined test pipes. The work to be carried out at Imperial College will be experimental and numerical. The former will focus on examining the spatio-temporal evolution of waves in churn and annular flows in annulus geometries; the latter will use interface-tracking methods to perform simulations of bubbles in two-phase flow and will also focus on the development of a computer code capable of predicting reliably the flow behaviour in large diameter pipes. This code will use as input the information distilled from the other work-packages regarding the various flow regimes along the pipe.