Thomas Doe

Bio: Thomas Doe is an academic researcher from Golder Associates. The author has contributed to research in topics: Hydraulic fracturing & Scale (ratio). The author has an hindex of 7, co-authored 29 publications receiving 299 citations.

State of stress, permeability, and fractures in the Precambrian granite of northern Illinois

Abstract: In situ fracture logging, permeability tests, and stress measurements have been conducted in UPH 3, a 1600-m-deep hole drilled into the Precambrian granitic basement of northern Illinois. Two major fracture zones are revealed, which cannot be discerned in UPH 2, a similarly deep hole about 1 km away. The segments of the UPH 3 core that were oriented indicate the existence of three sets of subvertical joints striking at N55°E, N40°W and E–W. These sets correspond to surface and shallow borehole joint directions in the Precambrian and Paleozoic rock of southern Wisconsin as well as other areas of the Midwest. The permeability values in UPH 3 display an overall reduction with depth from about 10−4 darcy at 700 m to 10−8–10−9 darcy at 1600 m. Permeability is highest in the zones of greatest fracturing, one of which occurs near the top of the granite and is probably related to fractures which were formed when the granite was at the surface in late Paleozoic times. Permeability reduction with depth is consistent with previous laboratory and field results in crystalline rocks. Hydrofracturing measurements in UPH 3 reveal a compressional stress field with the largest stress horizontal and oriented at N48°E (±30°). Based on linear regression of 13 test results in the depth range of 686–1449 m, the greatest horizontal stress has a magnitude of [20.5+(0.023×depth(m))] MPa. The least horizontal compression has a value of [8.7+(0.019×depth(m))] MPa. The vertical stress, based on density measurements, is given by [−1.3+(0.026xdepth(m))] MPa. Both magnitudes and directions support previous results in the technically stable Great Lakes region of the midcontinent. However, a mb = 4.4 earthquake did occur in 1972 some 90 km south of UPH 3, at a depth of 13 km. The focal mechanism solution revealed strike slip motion with the pressure axis horizontal and trending northeast, in accord with our measured stress directions and relative magnitudes but not predicted from a frictional sliding criterion based on Byerlee's law.

A Discrete Fracture Network Approach For Evaluation of Hydraulic Fracture Stimulation of Naturally Fractured Reservoirs

Abstract: This paper describes the development of a 3-dimensional Discrete Fracture Network (DFN) approach for simulation and evaluation of hydraulic fracturing in low permeability fractured rock in the FracMan® reservoir analysis tool. The approach is based on an empirical algorithm approximating the effect of natural fractures and in situ stress on hydraulic fracture propagation. The algorithm distributes frac-fluid between the propagating hydraulic fracture and pre-existing natural fractures to predict both the geometry of the hydraulic fracture, and the reactivation of the natural fracture network. The technique is demonstrated by comparison against ELFEN geomechanical simulations, and by comparison of simulated and observed microseismic responses. • The geometry, mechanical, and flow properties of the natural fracture system. • The configuration and operation of the hydraulic injection process itself. 2.1 In Situ Effective Stress Since hydraulic fracture propagation generally occurs in tension, the minimum principal stress determines both the direction and extent of the hydraulic fracture. In many tectonic settings, the vertical stress is the major principal stress, with the maximum and minimum horizontal stresses on the order of 60% or more of the lithostatic stress. The lithostatic (vertical) stress (σσvv) is often estimated by integration of the density log from the well bottom-hole location to the surface, using

Close Observation of Hydraulic Fracturing at EGS Collab Experiment 1: Fracture Trajectory, Microseismic Interpretations, and the Role of Natural Fractures

Abstract: Author(s): Fu, P; Schoenball, M; Ajo-Franklin, JB; Chai, C; Maceira, M; Morris, JP; Wu, H; Knox, H; Schwering, PC; White, MD; Burghardt, JA; Strickland, CE; Johnson, TC; Vermeul, VR; Sprinkle, P; Roberts, B; Ulrich, C; Guglielmi, Y; Cook, PJ; Dobson, PF; Wood, T; Frash, LP; Huang, L; Ingraham, MD; Pope, JS; Smith, MM; Neupane, G; Doe, TW; Roggenthen, WM; Horne, R; Singh, A; Zoback, MD; Wang, H; Condon, K; Ghassemi, A; Chen, H; McClure, MW; Vandine, G; Blankenship, D; Kneafsey, TJ | Abstract: The final version of the above article was posted prematurely on 16 July 2021, owing to a technical error. The final, corrected version of record will be made fully available at a later date.

VALIDITY OF CUBIC LAW FOR FLUID FLOW IN A DEFORMABLE ROCK FRACTURE - eScholarship

Abstract: The validity of the cubic law for laminar flow of fluids through open fractures consisting of parallel planar plates has been established by others over a wide range of conditions with apertures ranging down to a minimum of 0.2 µm. The law may be given in simplified form by Q/Δh = C(2b)3, where Q is the flow rate, Δh is the difference in hydraulic head, C is a constant that depends on the flow geometry and fluid properties, and 2b is the fracture aperture. The validity of this law for flow in a closed fracture where the surfaces are in contact and the aperture is being decreased under stress has been investigated at room temperature by using homogeneous samples of granite, basalt, and marble. Tension fractures were artificially induced, and the laboratory setup used radial as well as straight flow geometries. Apertures ranged from 250 down to 4µm, which was the minimum size that could be attained under a normal stress of 20 MPa. The cubic law was found to be valid whether the fracture surfaces were held open or were being closed under stress, and the results are not dependent on rock type. Permeability was uniquely defined by fracture aperture and was independent of the stress history used in these investigations. The effects of deviations from the ideal parallel plate concept only cause an apparent reduction in flow and may be incorporated into the cubic law by replacing C by C/ƒ. The factor ƒ varied from 1.04 to 1.65 in these investigations. The model of a fracture that is being closed under normal stress is visualized as being controlled by the strength of the asperities that are in contact. These contact areas are able to withstand significant stresses while maintaining space for fluids to continue to flow as the fracture aperture decreases. The controlling factor is the magnitude of the aperture, and since flow depends on (2b)3, a slight change in aperture evidently can easily dominate any other change in the geometry of the flow field. Thus one does not see any noticeable shift in the correlations of our experimental results in passing from a condition where the fracture surfaces were held open to one where the surfaces were being closed under stress.

A model for the hydrologic and climatic behavior of water on Mars

Abstract: An analysis is carried out of the hydrologic response of a water-rich Mars to climate change and to the physical and thermal evolution of its crust, with particular attention given to the potential role of the subsurface transport, assuming that the current models of insolation-driven change describe reasonably the atmospheric leg of the planet's long-term hydrologic cycle. Among the items considered are the thermal and hydrologic properties of the crust, the potential distribution of ground ice and ground water, the stability and replenishment of equatorial ground ice, basal melting and the polar mass balance, the thermal evolution of the early cryosphere, the recharge of the valley networks and outflow, and several processes that are likely to drive the large-scale vertical and horizontal transport of H2O within the crust. The results lead to the conclusion that subsurface transport has likely played an important role in the geomorphic evolution of the Martian surface and the long-term cycling of H2O between the atmosphere, polar caps, and near-surface crust.

Sharp increase in central Oklahoma seismicity since 2008 induced by massive wastewater injection

Abstract: Unconventional oil and gas production provides a rapidly growing energy source; however, high-production states in the United States, such as Oklahoma, face sharply rising numbers of earthquakes. Subsurface pressure data required to unequivocally link earthquakes to wastewater injection are rarely accessible. Here we use seismicity and hydrogeological models to show that fluid migration from high-rate disposal wells in Oklahoma is potentially responsible for the largest swarm. Earthquake hypocenters occur within disposal formations and upper basement, between 2- and 5-kilometer depth. The modeled fluid pressure perturbation propagates throughout the same depth range and tracks earthquakes to distances of 35 kilometers, with a triggering threshold of ~0.07 megapascals. Although thousands of disposal wells operate aseismically, four of the highest-rate wells are capable of inducing 20% of 2008 to 2013 central U.S. seismicity.