Optical imaging, including infrared imaging, generally has many important applications, both civilian and military. In recent years, technological advances have made multi- and hyperspectral imaging a viable technology in many demanding military application areas. The aim of the CEPA JP 8.10 program has been to evaluate the potential benefit of spectral imaging techniques in tactical military applications. This unclassified executive summary describes the activities in the program and outlines some of the results. More specific results are given in classified reports and presentations. The JP 8.10 program started in March 2002 and ended in February 2005. The participating nations were France, Germany, Italy, Netherlands, Norway, Sweden and United-Kingdom, each with a contribution of 2 man-years per year. Essential objectives of the program were to: 1) analyze the available spectral information in the optronic landscape from visible to infrared; 2) analyze the operational utility of multi- and hyperspectral imaging for detection, recognition and identification of targets, including low-signature targets; 3) identify applications where spectral imaging can provide a strong gain in performance; 4) propose technical recommendations of future spectral imaging systems and critical components. Finally, a stated objective of the JP 8.10 program is to "ensure the proper link with the image processing community". The presentation is organized as follows. In a first step, the two trials (Pirrene and Kvarn) are presented including a summary of the acquired optical properties of the different landscape materials and of the spectral images. Then, a phenomenology study is conducted analyzing the spectral behavior of the optical properties, understanding the signal at the sensor and, by processing spectroradiometric measurements evaluating the potential to discriminate spectral signatures. Cameo-Sim simulation software is presented including first validation results and the generation of spectral synthetic images. Results obtained on measured and synthetic images are shown and discussed with reference to two main classes of image processing tasks: anomaly detection and signature based target detection. Furthermore, preliminary works on band selection are also presented which aim to optimize the spectral configuration of an image sensor. Finally, the main conclusions of the WEAG program CEPA JP8.10 are given.
model is to show that these modeling methods are critical for the development of enhanced geothermal systems (EGS). This includes the prediction of rock behavior during fracturing and during an extended period of water flow between the parallel injection and production boreholes. Understanding the results from the induced fracturing and flow is complicated by the presence of significant natural fractures that interact with the stimulation and/or flow pathways. The delineation and characterization of natural fractures is thus an important part of the project, and therefore a model of the Discrete Fracture Network (DFN) was developed on a deterministic basis. The DFN was populated using observations and interpretations integrated from drift (horizontal passageways that allow access in the underground) fracture mapping, analysis of core recovered from the eight boreholes, borehole televiewer logs and videos, and observations of flow between and within boreholes and in the drift. The natural fracture system is dominated by a pervasive northwest-trending, steeply dipping shear system that is identifiable in the drifts and the core. Hydraulic fracture stimulation, flow/tracer circulation tests, and geophysical monitoring revealed that the behavior of the injected water, and perhaps the growth of induced fractures, has been significantly influenced by the existing fractures identified in the DFN.
ABSTRACT: The EGS Collab project is focused on understanding and predicting permeability enhancement and evolution in crystalline rocks to support geothermal energy production. To support this effort, the project is creating a suite of intermediate-scale test beds coupled with stimulation and interwell flow tests that will provide a basis to better understand the fracture geometries and processes that control heat transfer between rock and stimulated fractures. Therefore, high level site characterization is paramount for building models to estimate potential interwell flow rates and heat exchanges. For the second experimental testbed, the EGS Collab team visually mapped the distribution, orientation, and nature of open and healed fractures exposed along the drift wall in the Sanford Underground Research Facility 4100 feet below ground surface, and within the eleven boreholes drilled for this test bed. Continuous core logging of each borehole and a suite of geophysical wireline logs was collected to characterize the spatial variability of rock properties and fracture orientations. All of the data were then compiled into multiple 3D visualization software packages for interpretation and further analyzed for slip and dilation tendencies that will be incorporated into coupled-process geomechanical flow and transport models to better constrain the planned flow and tracer tests. 1. INTRODUCTION Following the completion of Experiment 1 at 4850 feet below ground surface (the 4850 level), the EGS Collab team initiated the development of a second testbed for Experiment 2 (E2) in the Sanford Underground Research Facility (SURF and former Homestake Gold Mine) in Lead, South Dakota, USA. The overarching goal of the EGS Collab project is to create field test beds to host stimulation and interwell flow tests that will provide improved understanding of fracture stimulation methods, resulting fracture geometries, and processes that control heat transfer between rock and stimulated fractures for Enhanced Geothermal Systems (EGS). This experiment will contrast from Experiment 1 in that its goal is to create a series of hydro shear fractures for interwell flow tests in support of the EGS Collab project (Kneafsey et al., 2018) at the intermediate-scale (~10-20 m). In the winter-spring of 2021, the EGS Collab team started to develop the E2 testbed on the 4100 level (1.25 km below the ground surface).
