Using a Dynamic Mechanical Earth Model and Integrated Drilling Team to Reduce Well Costs and Drilling Risks in San Martin Field

摘要

This paper briefly describes a process developed to reducedrilling risks and well costs and gives details on its applicationto three deviated development wells in Camisea, Peru.Previous offset vertical and deviated wells in this areaencountered wellbore instability, drilling fluid loss, andreactive shales. In some cases these events made it necessaryto drill multiple sidetrack wells.The process provided specific advantages while drillingtechnically difficult trajectories. Integral to the process wasdevelopment of a mechanical earth model (MEM) forprediction of drilling events and down hole drilling riskmanagement. The model, created using data from multipledisciplines (seismic, drilling, geology, wireline logs, coretesting), enabled the drilling team to understand potentialdrilling hazards and quickly act to mitigate risks, as well as tomake rapid informed decisions while drilling. Examplesdemonstrate how the process compared forward predictionswith actual results and how the model was updatedduring drilling.The first well reached total depth (TD) 5 days ahead ofschedule even though the trajectory was in a difficult stressazimuth and several nondrilling problems occurred.Teamwork and communication among the drilling locationand four offsite offices played a critical role in the decisionprocess. Predrill predictions matched post-drill information inmost cases. Lessons learned from the first well were applied tosubsequent well plans.This process can be applied to any exploratory ordevelopment well, but high-risk, high-cost wells receivemaximum benefit. Although wellbore instability resultingfrom tectonic stress was the main risk in this field, the processis equally valid for drilling issues such as overpressuredregimes, underbalanced drilling or extended-reach wellbores.