Salt drilling in offshore projects has become more frequent over the last 10 years in many parts of the world. In Brazil, important oil discoveries were made in carbonates reservoirs that lay below thick salt bodies. Drilling through salt can be challenging, especially where severe salt mobility is common. Salt mobility or creep rate is mainly a function of downhole temperature, geomechanical stresses around the salt body and salt mineralogy.

Today, many deepwater wells targeting hydrocarbons below the salt in Brazil are still considered exploratory or appraisal, and are drilled vertically through salt, with only a few projects in the development phase. Due to the gradual transition of deepwater projects into the development phase, the requirement for directional drilling through salt is rapidly increasing.

To achieve a better understanding of the salt drillability, in terms of steerability capabilities and directional assembly stability, a pioneer directional drilling test was conducted in a mobile onshore Brazil salt formation, using an advanced rotary steerable system (RSS) and a specialized downhole drilling optimization measurement-while-drilling (MWD) tool. This paper will show, in detail, the results and lessons learned from this unique salt drilling steerability test, along with the result of deepwater sections drilled directionally through salt formations offshore Brazil.


Directional drilling through salt has been perceived by the drilling community to be a challenge due to the plastic nature of the evaporates and due to wellbore stability problems commonly experienced in the past. The ability to consistently perform directionally in salt and achieve the planned buildup rates (BURs) had been an issue in salt throughout the years. In general many aspects rule the BUR capability in salt: The evaporate rock being drilled, salt creep rate, and bottomhole assembly (BHA) and bit design, among others. The directional drilling technologies evolution over the last years, along with the experience gathered in salt drilling worldwide, had given more confidence for operators and service companies to venture in directionally drilling through salt intervals.

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