Estimates Offshore Estimating

Having defined and gathered data adequate for an initial reserves estimation, the next step is to look at the various options to develop the field. The objective of the feasibility study is to document various technical options, of which at least one should be economically viable. The study will contain the subsurface development options, the process design, equipment sizes, the proposed locations (e.g. offshore platforms), and the crude evacuation and export system. The cases considered will be accompanied by a cost estimate and planning schedule. Such a document gives a complete overview of all the requirements, opportunities, risks and constraints. 

After having proved the principles a dynamic test facility has been constructed. In this facility it is possible to inject 3 tracers in a flownng liquid consisting of air, oil and water. By changing the relative amounts of the different components it is possible to explore the phase diagram and asses the limits for the measurement principle. Experiments have confirmed the accuracy in parameter estimation to be below 10%, which is considered quite satisfactorily for practical applications. The method will be tested on site at an offshore installation this summer. 

Bilhons of metric tons of phosphate rock also are present offshore in the oceans, eg, best estimates are that a biUion tons of pellets that may contain about 30% P2 5 present in a Baja California—Mexico deposit alone. Other areas in the world that contain large, unevaluated amounts of phosphate include AustraUa, Alaska, Africa, the Near East, Pern, Colombia, Brazil, the People s RepubHc of China, MongoHa, and the former Soviet Union. 

The Offshore and Coastal Dispersion (OCD) model (26) was developed to simulate plume dispersion and transport from offshore point sources to receptors on land or water. The model estimates the overwater dispersion by use of wind fluctuation statistics in the horizontal and the vertical measured at the overwater point of release. Lacking these measurements the model can make overwater estimates of dispersion using the temperature difference between water and air. Changes taking place in the dispersion are considered at the shoreline and at any points where elevated terrain is encountered. 

Specialized studies are investigations that attempt to verify the ability of a facility to perform effectively during an emergency, generally by mathematical estimates. They are used extensively to justify the necessity or deletion of a safety system. The most common studies are listed below however every facility is unique and may require it s own investigative requirements (e g., for an offshore facility - the potential for ship collisions). For example, for a simple unmanned wellhead... 

The physical approach is not undisputable, as it does not take into account the conditions of the occurrences or of the production of the crude oil (e.g., onshore or offshore, water depths, climatic conditions, etc.). Therefore, some authors give a narrower definition of conventional oil. Campbell (2006), for instance, considers crude oil that is found under deep-water conditions (water depths greater 500 m) or in arctic regions, as well as NGL as unconventional oil. As a consequence, the remaining potential of conventional oil is estimated to be lower. 

Windparks - Killer-Kriterien , grobe Auslegung, Kostenabschatzung -Hydrogen Production in Offshore Wind Parks - Killer Criteria , Basic Design, Cost Estimation 2001)... 

Estimates of recent inputs to Narragansett Bay (RI, USA), accumulation rates within the sediments of the Bay, and losses from the Bay to the atmosphere and offshore waters for major nutrients, various heavy metals, and total petroleum hydrocarbons. 

According to the estimates of the Bank of International Settlements, the total assets of so-called Group of Ten offshore banking centers, the unregulated islands and enclaves where "bank inspector" is a dirty word, amount to 94,349 billion, or close to 100 billion, as of February 1977. The figures break down as follows ... 

Eront-End Engineering and Design (FEED) focuses on obtaining accurate cost estimates for the major items of process equipment and further definition of the most sensitive parts of the overall project cost. It is denoted Eront-End because this is performed prior to final corporate board and financial approval for the overall project. EEED costs typically 5 to 10% of the overall project cost - thus for a 1,000 million project expenditure of about 100 million will be required. Only after the feasibility and FEED will the cost error be in the vicinity of +1-5%. In many instances, especially for new technology or for a remote location or offshore, the error will still be in the region of +/-10% or more. 

The offshore advective flux for Si shown in Fig. 17.3 (30 X 10 mol d l) was calculated by difference, based on the total flux of dissolved Si supplied to the shelf system (32 X 10 mol Si d-1), the estimated deltaic burial rate (1-3 x 10 mol Si d ), and the nearshore particulate flux (0.1-0.7 x 10 mol Si d ). This advective flux is in good agreement with the results of Daley (1997), who estimated that 30 x 10 mol d of Si leave the shelf, based on seasonal field data and a multibox model for the shelf. Most of the silicate (94%) supplied to the shelf by external sources appears to be transported to the open ocean in either dissolved or particulate form. Approximately 36% of the Si leaving the outer shelf is in particulate form according to these calculations. Biogenic silica export may have contributed to the lack of closure in the Edmond et al. (1981) silicate budget for the shelf, although deltaic burial also remains as a potentially important sink. 

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