A Comprehensive Fracture Diagnostics Experiment: Part 1—An Overview

Abstract

A comprehensive field fracture mapping experiment was performed in 1983-84 in Mounds, OK, south of Tulsa. The target zone was the Skinner sandstone, a deltaic formation roughly 80 ft [24 m] thick found at a depth of 1,020 ft· [311 m]. The first two phases of testing-extensive prefracture testing-included in-situ stress tests and minifracture treatments designed to extract the maximum amount of information about the possible orientation and azimuth of the hydraulic fracture to. determine the optimum experimental procedure for the final stage of the tests, in which a fracturing treatment with a magnetized proppant would be performed. The primary goal of the experiment was to measure the transport characteristics and final distribution of the magnetic proppant with surface and borehole magnetometers. Secondary goals included extensive data acquisition to determine fracture geometry by different methods, including various types of seismic monitoring and tiltmeters. This paper, an overview for the entire experiment, focuses on the role the first two phases of the test played in the experimental design for the final phase, explains the nature of the fracture diagnostic procedures used, and summarizes the operations performed and the results obtained during the three phases of the testing. Where appropriate, conclusions regarding the degree of success of the different diagnostic methods and their potential applicability at more commercial ,depths are discussed.

Seismic wave motion for a new model of hydraulic fracture with an induced low‐velocity zone

“…Since the pretreatment permeability of the Skinner Formation at the Mounds experiment was relatively high (10-20 mdarcy) [Fitz-Patrick et al, 1985], it was uncertain if the seismic observations and inferred conclusions were unique to the experiment and the geological setting or were more universal and hence contained potentially useful information. The concern regarding uniqueness of the Mounds data sets were obviated with subsequent borehole seismic data acquired at treatments in the Wattenberg Gas Field, Colorado, and the Cotton Valley Formation, Texas.…”

A Validation Assessment of Microseismic Monitoring

“…Various types of electromagnetic techniques (Bartel et al 1976;Fitz-Patrick et al 1986;Basu and Sharma 2014) might be usable for validation of some properties, but the authors are not aware of any such cases at this time. Similarly, some alternate seismic technologies, such as the use of seismic scattering information, might be usable for evaluating fracture characteristics, but the authors are not aware of any cases where they have been used for microseismic validation.…”