Western offshore fields in the South and East Asia region are depleted and require frequent stimulation. To efficiently deliver stimulation treatments, a supply vessel has been converted into a well stimulation vessel with limited well flowback capability. This is one of only a few vessels in the world that has a zero-discharge flowback facility with certification by industry-recognized external organizations. Developing the vessel and operations plans required a systematic approach to continuous improvement. The process involved identifying the criteria for efficiency and effectiveness for an offshore stimulation vessel and building in continuous improvement methodology with a focus on visual order, organization, safety, and standardization of operations. A lean management methodology was applied to systematically analyze and improve operational process efficiency in relation to organization, orderliness, cleanliness, adherence, and self-discipline. A series of checklists were introduced to enable procedural adherence with monthly self-evaluations to identify areas of improvement and develop remedial work plans. This paper describes the vessel conversion and installation process as well as the lean approach and health, safety, and the environment (HSE) requirements. The vessel has been used for a variety of stimulation jobs such as proppant fracturing, sand control pumping, matrix stimulation, nitrogen pumping, and limited flowback. These stimulation jobs have been achieved with no recordable injuries and zero nonproductive time by introducing operating procedures, training crew members in those procedures, and monitoring adherence. Systematic efficiency improvements related to materials and procedures led to a 23% reduction in onboard crew size, thereby reducing the risk exposure to personnel. Vessel repair and refabricating expenditures have been reduced by 53%. This vessel has delivered an average of 40 jobs per month, achieving a peak job frequency of 64 jobs per month and treating more than 1,000 wells to date. This paper provides an overview of the practices developed and lessons learned for operating an offshore stimulation vessel, including process flow charts with trackers and checklists designed to improve operational efficiency.

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This theoretical study about the development of a turbidite reservoir is unique because it considers the combination of the surface and the health, safety, and environment (HSE) constraints of the urban overlying the reservoir. Although geology poses deep challenges in terms of reservoir heterogeneity, anisotropy, compartmentalization, and pressure drives, the attempt to develop oil fields in an urban environment makes it very difficult to plan facilities, transport, services, and operations because of HSE issues. This study is a continuation of a previous study in which the background, modeling, and economic analysis of the earlier study is combined with stronger HSE concepts to make the study more holistic. With a strong focus on health and environment, this paper establishes guidelines for managing the risks of urban development. Reservoir management is guided by sensitivities and uncertainties on CAPEX and OPEX, establishing novel ways of optimizing infill well locations, drilling practices in a city, and enhancing hydrocarbon production through reservoir simulation practices. The geological, geophysical, and engineering data for the study are generated to represent analogous turbidite reservoirs whereas the HSE well planning recommendations are derived from urban oilfield developments in Los Angeles and Long Beach, California. The methodology of dynamic modeling is nonconventional in terms of analyzing the field for forecasting immediately after initialization followed by a detailed history match considering the numerous hurdles of turbidite environment. This allows greater time for field development planning, which is conventionally given the least attention because of time constraints. Therefore, the prediction comprises a no-further-action case, an infill wells case, and waterflood scenarios, with a combination of vertical and horizontal well trajectories exhibiting the best output in a span of vast economic sensitivities over multiple scenarios. The most noticeable part of the study is the wide range of realizations on well trajectories, well placement, optimizing drilling, and production services. Our modeled city was Houston, Texas, a well-known urban environment. As a result of the modeling, a technique was developed to guide for environmentally safe development within this example. The technological and economic conclusions make this a foundation study for profitable development of reservoirs underneath a populated area. The study may also be instrumental in exploitation of turbidite reservoirs, which present challenges in current North Sea and Brazil offshore development and in recently discovered submarine fans in the Gulf of Mexico deep marine environment.