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    • IsabelleF

      D5.4: Annual Risk Management Report 2

      Brief description :

      Executive summary: This document reports on the risks identified during field operations carried out in the second year of the PACIFIC project, from June 2019 to June 2020. During this period, two surveys were carried out at the Kallak iron ore project in Sweden and another was conducted at the Kaiserstuhl site in Germany.
      The document builds on D5.2 - Environmental and Safety Risk Database adopted in 2018, and D5.3 Annual Risk Management Report 1. The procedures outlined in these documents were implemented during the surveys. No injuries were reported in either survey and impact on the local environment was found to be minimal.

      Type of information :
      • IsabelleF

        D5.3: Annual Risk Management Report 1

        Brief description :

        Executive summary: This document reports on the risks identified during field operations carried out in the first year of the PACIFIC project, from June 2018 to June 2019. During this period, two surveys were carried out, one at Stillwater Canada Inc. (SCI)’ s Marathon PGU-Cu Project (“Marathon”), and another one at the Las Cruces site in Spain, an operating mine run by Cobre Las Cruces. The document builds on D5.2 – Environmental and Safety Risk Database adopted in 2018.
        The procedures outlined in these documents were implemented during the surveys. No injuries were reported in either survey and impact on the local environment was found to be minimal.

        Type of information :
        • IsabelleF

          D5.2: Environmental and Safety Risk Database

          Brief description :

          Executive summary: This deliverable gathers risks related to safety or environmental issues relevant for PACIFIC activities. For each type of issue, the risks/hazards are listed with their score before and after mitigation and the corresponding control measures. A safe working procedure is also described. This database will serve as reference for the ESMC – Environmental and Safety Risk Management Committee – for follow-up during the course of the project.

          Type of information :
          • IsabelleF

            D5.1: Environmental, Health, Safety and Risk Management Committee Charter

            Brief description :

            An ultimate Charter governing the roles, responsibilities, composition and membership of the Committee will be outlined and implemented prior to the activation of PACIFIC programs.

            Type of information :
            • IsabelleF

              D3.2: Successful extraction of body-wave data

              Brief description :

              Executive summary: A key goal of the PACIFIC project is to develop methodologies for the extraction of body waves from passive seismic data, for use in the environmentally sustainable environments. Recovering body waves from ambient noise data has proved to be challenging as they are usually weak and ambient noise fields are rich in surface waves. Here we propose and test a method, based on the Radon Transformation, that helps suppress surface waves and enhance reflected body waves. The method exploits the ‘moveout’ differences between reflected body (hyperbolic) and surface waves (linear) and is tested on synthetic 2D & 3D model data prior to its application to ambient noise field data. We refer to it as Radon Correlation. Synthetic tests are very encouraging, showing clear body wave recovery that cannot be seen in raw cross-correlated data. Using these synthetics to have a choice of parameters, we then move to field passive data from the Marathon site within PACIFIC. We generate virtual shot gathers by applying Radon Correlation to single virtual sources into a linear array of receivers. Again, results are very encouraging with clear reflected body wave recovery from the ambient noise data and determined by clear hyperbolic arrivals on the virtual shot gathers. There is a hint that using time windows that contain active blast seismic coda possibly further enhances body wave recovery. Finally, velocity analysis on these virtual shot gathers leads to a P-wave velocity model that compares well with models derived from surface wave dispersion analysis of the same ambient noise data. However, these models are not currently publicly available and hence are not shown here, in this report.

              Type of information :
              • IsabelleF

                D3.1: Deployment complete

                Brief description :

                Executive summary: Permitting of the seismic survey and the acquisition of data are the first steps in WP3, the pilot test of the passive reflection seismic technique in the Marathon deposit. The processing and development stages of the Work Package rely directly on the successful acquisition of ambient seismic noise data from the Marathon test site.
                Between September 17th and October 26th of 2018, at the Marathon test site, a 1025 sensor passive seismic survey was completed. The sensors equipment was rented from SAExploration. 1024 sensors were successfully deployed; however, only 1019 were recovered. The loss of sensors was due to animal activity or being buried by a rock slide.
                The grid design was composed of two overlapping grids, a 416-sensor array and a 609-sensor profile line. The array had a grid spacing of 150m, while the profile line had a grid spacing of 50m. Both grids designs were configured along the main noise source of Lake Superior in the direction of 250deg to the west.
                The sensors selected for the survey were ZL and C1, vertical direction sensors with a 10hz range. Once the sensors were retrieved, they were shipped back to SAExploration for download. The data was successfully downloaded and shipped to Sisprobe for analysis.

                Type of information :
                • IsabelleF

                  D1.4: Development of a physical parameter model for seismic wave simulations

                  Brief description :

                  Executive summary: Active seismic sources such as explosives, air guns and vibroseis generate energetic P-waves well suited for reflection seismic studies. However, they can have negative environmental impacts and are expensive, both of which have motivated the development of passive seismic methods. Passive seismic methods utilise ambient noise from meteorological and anthropogenic activity. They have been successful for surface wave recovery but extracting body waves for reflection imaging is still a challenge. A key goal of the PACIFIC project is to develop methodologies for extracting body waves from passive seismic data, and for using these body waves for subsurface imaging. This report describes the development of synthetic velocity models that characterise the geological structure and seismic reflectivity at the Marathon Cu-PGE prospect Ontario, Canada. Synthetic seismic signals generated in these models will then be used to develop and test processing procedures for body wave recovery and body wave imaging. A first velocity model consists of two vertical sections obtained by interpolation of lithological contacts identified in drillholes. One section is perpendicular to the dip of the main gabbro intrusion, the other is parallel. A second model is obtained by blind 3D interpolation between drillholes and uses velocities measured on hand samples and drill core. Work in progress uses dedicated geological modelling software to generate a 3D block model that honors geological structures and cross-cutting relationships. A recently acquired downhole acoustic log avoids negative velocity biases from microfractures that can be introduced during depressurisation (e.g. of drill core). This will be used to calibrate a new velocity forward model.

                   
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                  • IsabelleF

                    D1.3: Report comparing best practice in active and passive exploration methods

                    Brief description :

                    Executive Summary: Seismic methods provide high-resolution images of geologic structures hosting mineral deposits and, in a few cases, can be used for direct targeting of deposits. Active reflection techniques have been successfully used in the minerals sphere, especially for structural control on deep targets. Although useful, a disadvantage of this methodology is that it is expensive and logistically difficult in locations without easy access for source generation. In contrast to active seismology, passive methods exploit ambient seismic noise and do not require specific seismic sources. In this report, we compare active and passive seismic methods in general and discuss different data processing sequences that have been used in previous passive seismic studies. The quality of the results in passive seismic methods strongly depends on (1) the spatial-temporal properties of the noise source distribution and (2) the number and disposition of seismic receiver pairs on which the noise correlation is performed. We then discuss how to apply these processing sequences to extract body-waves in the PACIFIC project, with a view to developing reflection seismic images analogous to active reflection seismic work.

                     
                    Type of information :
                    • IsabelleF

                      D1.2: Report on the physical properties and seismic characteristics of ores and host rocks

                      Brief description :

                      Executive summary: The physical properties of rocks and minerals, particularly their density and elasticity, control the velocitywith which they transmit seismic waves. The acoustic impedance, which is the product of density and seismic velocity, is a useful property to characterize different lithologies. Available data indicates that there are strong contrasts in acoustic impedance between common types of rock and, most importantly, between common rocks and ore minerals. These differences provide a basis for relating passive seismic tomographic models with models based on geological and previously acquired geophysical data.

                       
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                      • IsabelleF

                        D1.1: Assessment of successful active seismic processing workflows

                        Brief description :

                        Executive summary: Across the globe, the mineral industry is seeking new technologies to replace or complement existing geological, geochemical and geophysical methods to improve exploration efficiency at depth and to help design safer and more productive mines. These industries are increasingly using seismic methods for a wide range of commodities including base metals, uranium, diamonds, and precious metals. Seismic methods usually can be used for direct targeting of mineral deposits but particular care must be taken during acquisition and processing of the data. To achieve the best results, different processing sequences based on the target of the project are applied. Here we compare and discuss how such workflows are used when treating active seismic data in order to provide a basis for their use in the development of the passive seismic methods that form the basis of the PACIFIC project.

                         
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