As an innovation in the EU-funded H-2020 GREENPEG project (GA 869274), the Geological Survey of Norway (NGU) has developed a state-of-the-art piezoelectric seismograph (PE) as a valuable contribution to pegmatite exploration. The instrument utilizes the piezoelectric effect which describes the conversion of mechanical pressure, such as vibration or strain, into electrical energy, or vice versa. This technology has been leveraged to detect quartz, in particular for gold exploration, since the 1970s. NGU applied newest electrotechnology and data acquisition and processing to customize it for granitic pegmatite exploration. The pilot was deployed in different settings e.g. at the GREENPEG demonstration sites in Tysfjord, Norway, and could successfully detect buried quartz deposits, confirmed by drill cores. In the Tysfjord/Drag pegmatite field, the quartz core of the NYF pegmatite (Niobium-Yttrium-Fluorine) was detected at a depth of 5–10 m and underneath a 1-2 m thick quaternary overburden using minimal invasive explosive charges of ca. 100g. At a second site in Tysfjord/Håkonhals the quartz was found at even 15–25 m depth embedded in the host rocks amphibolite and gneisses, while using an 80 kg drop-weight with minimal environmental impact.

Figure 1. The NGU developed piezoelectric seismograph was deployed at the GREENPEG Tysfjord demonstration site in Håkonhals and Drag. A) shows a sketch of the developed system and B) the recorded and pre-processed signal produced from C) an 80kg drop-weight as seismic source

Since this novel piezoelectric seismograph is exclusively sensitive to the presence of quartz, it has a much lower ambiguity compared to other geophysical methods applied in pegmatite exploration and is a sustainable and cost-efficient method for this type of exploration, both as a stand-alone method or in combination with other methods on brownfields and greenfields.

Some partners of the GREENPEG Project Consortium gave support to the media artist Dr Stephen Cornford https://stephencornford.net/ and spent quite some time with him in the field in Tysfjord, Wolfsberg and in Leinster (project demonstration sites) assisting him with questions and guiding him in the field sites. Having visited all three locations, Stephen documented a wide range of the exploration tools and devices used in GREENPEG, recorded some typical scenes of people doing geophysical work and took videos from stills and made sound records such as the internal clicking and beeping of some of the devices. More information will be given in our September issue of GREENPEG Newsletter. See also the video which is now online available for streaming here:

https://avantwhatever.xyz/w/tsSQUPENFwnYfwJTche3jh

Artist Biography

Stephen Cornford is a media artist who works with consumer electronics, critiquing the ideologies they embody and the constitutive role they have come to play in our lives. His current research is concerned with the toxicity of digital media, the complex metallurgy of ubiquitous technologies and relationships between planetary and photographic space.

Much of his recent work has been made in collaboration with scienctific researchers. He has worked alongside commercial geophysicists prospecting for technology metals in Europe and volcanologists studying magma crystallisation with X-rays. His practice often employs laboratory processes or scientific imaging, using geological furnaces to transform electronic waste or optoelectronics facilities to damage cameras.

Including the world-class spodumene pegmatites at Manono-Kitotolo presented by Prof Anouk Borst, KU Leuven. She will discuss the geology, as well as some socio-economic and political aspects of exploration and mining in DRC, in the context of widespread artisanal mining and conflict. Get familiar with this topic also by DER SPIEGEL International Article “China Battles West for Raw Material of the Future”. Do you wish to join GREENPEG SIMS? Subscribe by contacting us: contact@greenpeg.eu

GREENPEG partner NGU recently released a movie introducing into the developing of a cutting-edge piezoelectric instrument. While pegmatites are commonly thought to be relatively invisible to geophysical exploration methods, this approach addresses the susceptibility of, in particular, quartz pegmatites to respond to seismic deformation with an induced electric signal- the piezoelectric effect. The interpretation of the captured electric signal can aid in identifying and locating potentially buried pegmatite ores. The instrument's effectiveness and ability to play a significant role in the GREENPEG toolkit have been thoroughly tested with diverse seismic sources in varied geological environments. We are currently interpreting the data and refining the data acquisition process.