An Integrated In-Situ Stress Measurement Program for Deepwater Brown Field Developments Available to Purchase

The Mars field began production in the mid-1990s, and a wealth of direct and indirect stress measurements have been accumulated through drilling and completion operations over the years. Typical data collected over the years include casing shoe formation integrity tests, leak-off tests, lost circulation events while drilling, mini-frac during completions, and step-rate tests in the producing reservoirs. While this traditional dataset provides some basic insights into stress characterization around the basin, extrapolating these data for more specific operations can be challenging due to the complexity from various level of activities across the 70+ stacked sands. Some of the challenges in utilizing the traditional dataset includes defining waterflood injection limits and in managing drilling margin through severely depleted zones. To aid better decision making, some novel measurement programs have been conducted over the last few years such as cased-hole microfracture tests during abandonment of wellbores. More recently, a series of modified open-hole extended leak-off tests were conducted to define the impacts of drilling mud on fracture pressures where both depleted reservoir sands and bounding shales were exposed. These newly acquired data along with our traditional dataset provided the Mars asset new insights into the impacts of various operation decisions on fracturing potentials both in the caprock and through depleted reservoirs. This dataset also unlocked new reserves and opportunities within the basin. In this paper, we provide an overview on the various components of this unique in-situ stress measurement program that has significantly impacted both our development and operating philosophy at Mars.