During the full life cycle of an oil or gas field, the reservoir characteristics will invariably alter as the field is produced. In the same way as the dynamics of the reservoir will change, so too will the definition of a marginal field. According to the legal definition, marginal field refers to an oil or gas field that may not produce enough net income to make it worth developing at a given time. However, should technical or economic conditions change, such a field may become commercial field. It is usually associated with small pockets of hydrocarbons that have a plateau of a few years. Marginal fields have several parameters that affect them. This includes environmental concerns, political stability, access, remoteness and, of course, the price and price stability of the produced gas/liquids. This session will, therefore, focus on the variety of changes that will affect the definition of the marginal field. The session will include the following topics:
Risk management is at the heart of the oil and gas industry—indeed it is a vital exercise when considering the development of any field. It covers the complete range of industry technical and non-technical disciplines from geoscience to reservoir, production and facilities engineering to operations, marketing, commercial, finance, and HSE. The industry has developed a variety of tools and processes to manage risks, but are they effective? It is common to hear of fields not achieving the metrics, such as NPV, IRR, initial development cost and project schedule, set at the time development was approved. This suggests the industry is not managing risk effectively. Where have we been going wrong and how can we do it better?
Understanding the range of possible outcomes is important in any subsurface assessment. This is particularly challenging in marginal projects where there is an increased focus on ensuring we have assigned appropriate uncertainty ranges for key reservoir parameters. Managing subsurface uncertainties also involves ensuring we have incorporated all available field and analogue data, we have sufficient data to determine appropriate ranges, and understanding what additional information will give us the most value in terms of uncertainty reduction.
This session will include discussions on:
With the definition of marginal field, economics of the field is always challenging. Question has often come to the development team on development option. Due to high investment involved in petroleum development, early monetisation has always become the preferred option in order to manage subsurface uncertainty, while relieving the economic pressure and get the project to the break-even point with step by step approach. It is though understand that this choice is not so obvious depending on many factors including project set-up, business environment, economic model etc. This session will portrait the cases of early production showing lesson learnt from such marginal projects development and their results.
The marginal field developments are often stalled on CAPEX as the initial risked investment. Keeping this small is a major driver and one of the biggest components which can vary largely and effected by front end engineering is installation. The other high cost element is drilling. The successful marginal fields may well rely on clever designs which have a reduced installation and drilling cost. The discussions in the section relate to case histories and technologies which enable CAPEX reduction.
Innovative technical advances are now enabling operators to consider development of marginal fields previously identified as uneconomic or marginal. This session discusses how the uses of fit-for-purpose production facilities offer an alternative approach to marginal fields development. The session includes examples of facilities and approaches that enable operators to minimise their initial capital investment (Capex), to gather additional information on the performance, and productivity of their wells and to develop more comprehensive development plans for their fields. The session includes examples of innovative and fit-for-purpose production facilities which are cheaper than traditional production platforms which provide cost effective means to develop small and marginal fields. The session shares technical and design challenges of such facilities. The session includes examples of “lease-based” production facilities which minimises initial capital outlay of projects which can substantially improve project economics. The session includes examples technical and commercial challenges faced by operators and their considerations to develop small or marginal fields.
As the oil and gas industry moves forward, there is an increasing requirement for drilling deeper (wells), longer (laterals), farther (from shore). This introduces complexity at every stage from logistics, managed pressure drilling, and fit-for-purpose completions with minimal tripping requirements. The prediction, evaluation and assessment of the geopressure environment of green fields is critical, not only during the exploration phase, but also during development. Treating the matter with due detail increases the probability of reaching target depth safely and efficiently. This session will address considerations for drilling and completing real wells in challenging conditions.
Whilst a marginal field alone might appear not to produce enough net income to make it worth developing at a given time, there may be near field opportunities that can move such a field into a commercially viable situation. Near field exploration could lead to the identification of additional small hydrocarbon accumulations that alone would be uneconomic, but tied back into the primary marginal field could introduce an economic venture. Likewise appraisal considerations targeting a marginal field may also lead to improving the marginal status of the field. Appraisal wells may ultimately implement new techniques and technologies that result in improving reservoir delineation and productivity and/or defining a new reservoir target. The upside potential of a marginal field should consider a number of exploration and appraisal consideration, this session includes contributions focusing on the following areas: