Interaction between Crustal-Scale Darcy and Hydrofracture Fluid Transport: A Numerical Study

<div>Examples of hydrothermal breccias. (a) Teufelsgrund mine, Black Forest, Germany (47°50<svg height="11.4859pt" id="M1" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 3.89517 11.4859" width="3.89517pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>37<svg height="11.4859pt" id="M2" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 6.94594 11.4859" width="6.94594pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,3.038,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>N, 7°49<svg height="11.4859pt" id="M3" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 3.89517 11.4859" width="3.89517pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>14<svg height="11.4859pt" id="M4" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 6.94594 11.4859" width="6.94594pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,3.038,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>E). Breccia clasts consist of local but altered host rock. The matrix mostly consists of fluorite and barite. (b) Hidden Valley, Mt. Painter inlier, Northern Flinders Ranges, South Australia (30°05<svg height="11.4859pt" id="M5" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 3.89517 11.4859" width="3.89517pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>25<svg height="11.4859pt" id="M6" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 6.94594 11.4859" width="6.94594pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,3.038,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>S, 139°30<svg height="11.4859pt" id="M7" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 3.89517 11.4859" width="3.89517pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>28<svg height="11.4859pt" id="M8" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.4361 6.94594 11.4859" width="6.94594pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,3.038,-5.741)"><path d="M310 541L304 571C290 586 211 619 185 610L80 76L131 52L310 541Z"></path></g></svg>E). Clasts are a mix of various, heavily altered lithologies, such as metasediments (layered clast on right), basalts (dark clast bottom left), and basement gneisses.</div>

Geofluids

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Figure 1

Figure 1: Interaction between Crustal-Scale Darcy and Hydrofracture Fluid Transport: A Numerical Study 