Evaluate The Geothermal System, The Value Of Borehole Images Directions

Abstract

The economical exploitation of Geothermal reservoirs requires both cost efficient solutions and high recoverable rates. However, the evaluation and development of these resources are usually dependent on many operational risks. This fact causes increase in the operational costs and may dramatically hurt the investment and economic value of the project. This workflow built for the geothermal conceptual model that provides a new insight and more accurate description of the reservoir, it can be applied during exploration, appraisal and development for all stages of the field life. The conceptual geometrical models built by integrating geophysical, geological and development data. This allows modeler to construct more comprehensive subsurface reservoir models which provides the frame for numerical modeling required to estimate the heat distribution. Geoscientists often face significant challenges to generate conceptual models for the reservoir due to limited availability (and/or poor quality) of geophysical data and the difficulties validating these conceptual models with existing production and drilling observations. This workflow based on the fundamental concept of stratified rocks deformations and behavior; the rock will deform similarly under the same geological forces and processes. This concept is applicable whatever structure folds, drags and rollovers are observed. The proposed workflow constructs the structural surfaces from dipmeter data. These surfaces provide new sights for the conceptual models, which accurately describe the different structures in the vicinity of the well, whatever their scales. Thus, it becomes possible to examine the geological structures despite the lack of subsurface imaging or low vertical and lateral resolution of available geophysical surveys. It is devoted to extract structural information from any available dip information in order to facilitated 3D conceptual models building. It relies on the basic idea that each structure can be described as part of cylindrical or conical surfaces corresponding respectively to great or small circle on stereonet plot. Once structural frame built the fracture network modeling will define the quality of the reservoir by quantify the fracture permeability and capture very heterogeneous nature of the geothermal reservoir. These models will be validated by solving the geomechanical stress and strain state.

AAPG Datapages/Search and Discovery Article #90346 ©2019 AAPG European Region, 3rd Hydrocarbon Geothermal Cross Over Technology Workshop, Geneva, Switzerland, April 9-10, 2019