Publications

The cost of drilling in Indonesia is one component of oil and gas exploration costs which is taken into account in determining the recoverable costs. Drilling is expected to be done safely and as cheaply as possible, therefore should be planned considering the routine drilling rig operation, bit selection and all of the problems that could potentially occur during drilling operations. In many ways, the use of a drilling cost equation is useful in making recommendations to estimate the cost of the well. Cost estimates at a particular location are used to determine whether the wells can be drilled economically or not. Over the period 2009 – 2011, the cost of drilling in a gas field in the Mahakam delta shows a declining trend. This cost effectiveness was caused by the changes in the architecture of the well and optimization of drilling activity. Changes from standard hole to slim hole can be done if the subsurface conditions allow. Optimization can be done from the drilling program planning and at work by minimizing the Non Productive Time (NPT). Annual drilling cost savings of 22% are shown by the evaluation of the well cost per meter of measured depth. This paper will first provide a review of historical drilling cost data based on the depth interval drilled and processed to formulate drilling cost estimates. Then statistical methods based on a survey of drilling costs produces an estimated drilling cost formula through the plot and curve fitting of polynomial, exponential and power series. The equation generated is tested to the actual drilling cost in the Mahakam delta to ensure that the cost savings are reasonably acceptable.