  This document describes the functioning of the automated history matching and
optimization workflow implemented with the ResFrac hydraulic fracturing and
reservoir simulator. The purpose of the automated history matching and
optimization workflow is enable automated calibration of simulator models to
observed data and application to forward optimization. The automated workflow
works by solving a formal mathematical optimization problem to minimize misfit
with observations from any point in the lifecycle of a hydraulically fractured
reservoir, or to maximize a quantity of interest associated such a reservoir,
such as net present value. Objective function evaluations in the optimization
problem consist of runs of the ResFrac simulator, which is a physics-based
model of hydraulic fracturing and reservoir phenomena. The workflow employs a
proxy model to improve computational speed and applies experimental design and
Bayesian sampling techniques to generate points with which to train the proxy
model. This document also provides an overview of the software infrastructure
developed to support the automated workflow.
