Drilling though salt is not a new challenge in the petroleum industry, with successful exploration and appraisal wells in salt environments paving the way for complex field developments. A detailed summary of how these advancements have subsequently evolved into the technology and methods being used today is presented.
The numerous challenges, and the resulting solutions, of drilling in salt environments are well documented; a comprehensive review of the relevant published industry literature has been conducted. Additionally, workshops with several major service vendors have been held to ascertain the current status of research and new product development. These two areas form the foundation of this work and have been weaved together and presented to establish what is the state of the art in salt drilling.
Since the first salt wells were drilled, the drilling industry has changed considerably. Significant advancements in salt drilling technologies and methods have been made in areas such as: best drilling practices, salt formation geomechanics, salt formation geochemistry, drilling fluids, well cementing, directional drilling, drill string and drill bit design. These advancements have all been clearly delineated in a chronology of continuous improvement, compounded by the considerable weight of industry experience and lessons learned which has in turn led to optimisation, and increased efficiency, of salt drilling operations. Today, salt drilling is prevalent in areas such as the Gulf of Mexico, deep-water offshore Brazil, and deep-water West Africa, where the boundaries are continually pushed due to the perseverance of both petroleum operating companies and service vendors.
The existing body of literature on salt wells is large and covers many disciplines of the upstream business, from wildcat exploration through to production. However, this focus is solely on drilling, combining and summarising many years’ worth of experience, learning, research, and development, to present what is the state of the art in salt drilling.