Formation Integrity Test Method for Geothermal Wells

Abstract

Fracture gradient data is a critical data to observe in any drilled well (oil, gas or geothermal), under a well construction perspective and to safely drill to the next casing point. Fracture gradient data is critical to properly execute all the drilling phases and follow safe practices. Following proper well design techniques will allow the well to be safely shut in, mitigating underground well control issues. The fracture gradient data can be used to optimize future wells design, reducing costs in the same field, by allowing for the determination of the minimum number of casing strings required for safe drilling and completion. The step rate formation integrity test method is a safe and practical method of measuring the fracture gradient and leak-off pressure of any given well by minimizing the risk of inducing circulation losses while attempting to obtain the fracture gradient data, causing lost circulation that may lead to well control issues that in turn would increase cost. Ensuring that a well can be shut safely through proper design should significantly decrease underground well control issues.