Marko Holma

Muon Solutions Oy, Finland

Asarel-Medet JSC Mining and Processing Complex is the first, biggest and leading Bulgarian company for open pit mining and processing of copper and other types of ores. Asarel-Medet JSC is the only Bulgarian company that participates in the international research project AGEMERA to study the potential of Europe regarding critical raw materials for...

This study presents U-Pb age data obtained using an in situ LA-ICP-MS technique applied to wolframite samples from Polski Gradets (Bulgaria) and Barruecopardo (Spain). Analytical conditions were optimized using YGX2113 (wolframite) and GJ1 (zircon) natural standard reference materials (SRMs). Applying both SRMs, very similar U-Pb age results were o...

Journal: Geologi. Note: This article is in Finnish, but it contains an English summary. The work’s title is ’On the verge of a new kind of geophysics: Part 4 – Geoscientific and archaeological applications of muon imaging.' Tämä artikkeli on myonigrafaa eli myonikuvausta käsittelevän kirjoitussarjamme neljäs osa. Sarjan tarkoitus on tehdä tätä uutt...

A transition towards sustainable energy sources requires the exploration and development of minerals critical to electronics and energy storage and delivery systems. Funded under Horizon Europe (Grant Agreement N°101058178), the AGEMERA project is a three-year initiative addressing critical raw materials (CRMs), including their exploration and extr...

Attenuation muography, an innovative astroparticle geophysical technique, uses cosmic-ray muons to image the internal structures of objects based on the attenuation of muon intensity due to density. We applied it in the St. Christoph mine, a tourist attraction in western Erzgebirge, SE Germany. Mining of the local polymetallic ore containing Sn, Zn...

As wireless sensor networks (WSNs) with Internet of Things (IoT) devices become increasingly widespread and more complex, the threat of cyber-attacks is also increasing. One of the most common ways WSNs can be hijacked is when passwords/IDs are leaked. If the passwords do not frequently change, it is easier for the system to be compromised. However...

This overview provides a comprehensive insight into Callio Lab, a versatile multidisciplinary research platform, by describing the events and actions that have led to the development of the project-based, pay-by-service approach to organizing and economically running the research activities, a mandatory approach for a platform operating without gov...

Journal: Geologi. Note: This article is in Finnish, but it contains an English summary. The work’s title is ’On the verge of a new kind of geophysics: Part 3 — Simulations in muon imaging.’ Tämä artikkeli on myonigrafaa eli myonikuvausta käsittelevän kirjoitussarjamme kolmas osa. Sarjan tarkoitus on tehdä tätä uutta geofysikaalista menetelmää tutuk...

The present study provides geochemical and geochronological data about Posušje bauxites in Bosnia and Herzegovina with the aim to characterize them as Critical Raw Materials (CRMs) sources and to put constraints on the time and genesis of the deposit. Boehmite is the bauxites’ main Al-bearing mineral, while gibbsite is a minor constituent. Hematite...

The study presents petrographic and compositional data of Late Cretaceous bauxite deposits in the area of Jajce, Bosnia and Herzegovina. Results indicate that bauxites exhibit ooidic to pisodic textures enclosed within a pelitomorfic matrix. Most of the deposits are boehmitic but in some localities, a considerable quantity of diaspore is identified...

Muography takes advantage of the specific properties of cosmic-ray muons, relativistic leptons that are much heavier than electrons. Cosmic-ray muons have strong penetrating power and a relativistic nature, which means they can be used in a range of technologies, including imagery; positioning, navigation, timing (PNT); and secured communication in...

Muography takes advantage of the specific properties of cosmic-ray muons, relativistic leptons that are much heavier than electrons. Cosmic-ray muons have strong penetrating power and a relativistic nature, which means they can be used in a range of technologies, including imagery; positioning, navigation, timing (PNT); and secured communication in...

The digital and green transition aims to bring Europe as a NetZero CO 2 producer by 2050. The need for raw materials is increasing to reach these goals, especially in electrification of mobility, metal processing, renewable energy production and hydrogen economy. Some material needs can be met with recycling, some by substituting current critical r...

Petrographic, Mineralogical and Chemical Characteristics of Bauxite from Posušje Deposits, Bosnia and Herzegovina - AGEMERA Project Research

Tunnelling and underground mining face many risks threatening underground operations. Such hazards include sudden incidents of dangerous and violent rock bursts and cave-ins. We propose that stationary muography arrays in underground settings could map potentially risky areas.

Publication: Proceedings of the Geological Society of Finland, Volume 3, Abstracts of the 1st GeoDays 14th-17th March 2023, Helsinki, Finland. University of Helsinki, p. 44.

Note: This article is in Finnish, but it contains an English summary. The work’s title is ’On the verge of a new kind of geophysics: Part 2 — Muon detection and the basic principles of muography.’ Tämä artikkeli on toinen osa myonikuvausta esittelevien kirjoitustemme sarjassa, jonka tarkoitus on tehdä menetelmä tutuksi geotieteelliselle yhteisölle...

Note: This article is in Finnish, but it contains an English summary. The work’s title is ’On the verge of a new kind of geophysics: Part 1 — Muons and the most common applications of muography.’ Myonigrafia on aineen tiheyden uusi kuvantamismenetelmä. Se perustuu ilmakehässä syntyvien myonien havaitsemiseen, sen jälkeen kun ne ovat kulkeneet kuva...

The supply of European critical raw materials (CRMs) does not currently meet the European demand. This gap is predicted to increase, making Europe even more dependent on outside suppliers. AGEMERA is a project to help tackle this strategic problem by studying several CRM sites in Finland, Poland, Spain, the Balkans, and Zambia in different deposit...

The supply of European critical raw materials (CRMs) does not currently meet the European demand. This gap is predicted to increase, making Europe even more dependent on outside suppliers. AGEMERA is a project to help tackle this strategic problem by studying CRM sites in Finland, Poland, Spain, the Balkans, and Zambia. We conduct geological studie...

Cosmic-ray muography is a novel method for density characterization of gaseous, solid, and liquid materials in various dimensions and with numerous distinct technologies. The number of applications of muography is on a constant rise, as is also the number of authors, affiliations, journals, publishers, funding agencies, and countries that can be re...

Large-scale solid bodies on Earth such as volcanoes and man-made pyramids have been visualized with solid earth muography, and the recently invented technique, acqueous muography, has already demonstrated its capability to visualize ocean tides and tsunami. In this work, atmospheric muography, a technique to visualize and monitor the vertical profi...

Cosmic-ray geophysics is a subdiscipline of geophysics that multidisciplinary combines various geosciences with high-energy physics and relies on several types of instruments specifically designed for elementary particle detection. The cosmic-ray geophysical methods can be further divided into a couple of subfields, such as cosmogenic isotope geoch...

Cosmic-ray muography (or just muography) is a novel geophysical method based on the repeated directional measurements of particle flux of the elementary particle muon underneath or sideways of the volume of interest. This conference contribution discusses the possibilities of muography applied in porphyry copper environments.

Global demand for critical raw materials (CRMs) continues to grow rapidly, mobilizing Europe’s domestic potential. Europe has a long tradition of mining and extractive activities of copper and base metals but is less successful in projects to source CRMs. A new Horizon Europe project called ‘AGEMERA: Agile Exploration and Geo-modelling for European...

Muography is a novel geophysical method for imaging density contrasts in liquid or solid materials. Imaging is possible in 2D, 3D, and 4D (time) and scales from less than a meter to over 1 km. Here we explain the possibilities of muography in the hands of structural geologists and the mining industry.

The cosmic-ray muography is an emerging imaging technique that exploits the attenuation of the penetrative muons originating from the interactions between high-energy cosmic radiation and the atmosphere. We propose that the differential attenuation of muons in laterites, saprolites, bauxites and fresh rocks can be muographically employed in the stu...

Muography is an emerging geophysical method that exploits the attenuation of the penetrative muons in rocks and other materials. Muons are elementary particles originating from the upper atmosphere as high-energy cosmic rays constantly bombard Earth. The high-energy muons are highly penetrative in solid materials, although their flux quickly dimini...

Muography has many possibilities ranging from imaging volcanoes to observing civil infrastructures, industrial targets, or even small-scale objects. G. F. Knoll has laid out the fundamentals of radiation detection and measurement of muon flux. However, what is still lacking is the testing and verification environments for muon detectors used in muo...

Cosmic-ray muography is a novel methodology for monitoring and spatial imaging density variations in solid and liquid materials. The capabilities of muography are particularly fitting for studying bedrock fractures, weathering and the inner structure of different landforms. Detectors must be positioned behind the open sky (the source of muons) and...

The heritage mining waste storage facilities, such as tailings ponds and waste rock stockpiles, are today considered significant secondary raw material resources by the EU. One of the methods that hold promise as a characterization method of heritage tailings and waste rocks in terms of the ore potential estimation is cosmic-ray muography.

We propose that cosmic-ray muography can be applied for studies of terrestrial impact craters.

Underground laboratories provide unique environments for science, research and business, but many are not known or stay underutilised. Some of the underground laboratories are located or are planned to be built around the Baltic Sea region. In this work, the main outcomes of the EUL and the BSUIN projects will be presented.

An isolated but highly connected underground mine can be used as an analogue environment for the astronauts operating without sight to the home planet and with limited connectivity to the psychologically-important "home". Similarly to the real-world space mission, the Earth-bound analogue mission can be run with limited resources, i.e., just enough...

Meteorological-tsunami-like (or meteotsunami-like) periodic oscillation was muographically detected with the Tokyo-Bay Seafloor Hyper-Kilometric Submarine Deep Detector (TS-HKMSDD) deployed in the underwater highway called the Trans-Tokyo Bay Expressway or Tokyo Bay Aqua-Line (TBAL). It was detected right after the arrival of the 2021 Typhoon-16 th...

Large-scale solid bodies on Earth such as volcanoes and man-made pyramids have been visualized with solid earth muography, and the recently invented technique, acqueous muography, has already demonstrated its capability to visualize ocean tides and tsunami. In this work, atmospheric muography, a technique to visualize and monitor the vertical profi...

The present work has one aim and one aim only: to increase the geological credibility of simulations of muon propagation in real-world rocks. We accomplish this by introducing five different sets of real-world geological systems. Our approach contrasts with the so-called "standard rock" approach, which uses a simplified rock composition as a proxy...

Cosmic‐ray muography has several current and many promising future applications in geosciences, geotechnical engineering, and mining engineering. Muography, if applied to these disciplines, is based on alternating muon flux attenuation in soils and rocks due to anomalous density heterogeneity in the media. Muography can be used for detecting and im...

Tidal amplification or tidal reduction as a response to sea-level variations can potentially amplify or mitigate the flood risk associated with future sea-level rise caused by global climate change. Tokyo Bay Seafloor Hyper Kilometric Submarine Deep Detector (TS-HKMSDD), the world’s first detector array located underneath the seafloor, has operated...

PLAIN-LANGUAGE SUMMARY Movements of hot aqueous fluids within the subsurface rocks typically take place along major structures such as fault zones. Fluids reacting with rocks along the structures altered their compositions and mineral contents. We propose a new tool for mapping the extent of these types of alterations by applying high-energy muon p...

Bauxites are mature laterites develop under a long period of extreme chemical weathering in a humid, tropical to subtropical climate. Bauxites are, in fact, among the best climate-sensitive rock indicators for warm and humid paleoclimates. They also represent a useful proxy for past climate changes and are important for provenance studies and geody...

Pyhäsalmi, in the Town of Pyhäjärvi, hosts one of the northernmost deep underground laboratories in Europe, the Callio Lab. Its origins are in underground physics (Centre for Underground Physics in Pyhäsalmi, CUPP), but gradually it has turned into a multi- and transdisciplinary research environment utilising both the surface and underground. Besid...

Cosmic-ray muography is a group of density-imaging techniques based on directional measurements of muon attenuation in liquid or solid media. The foundations of this emerging multidisciplinary research field were already laid in the 1950s-1970s, but the number of applications and research publications has witnessed a constant increase only in the l...

This work provides a few thoughts on a possible muography test and method validation site located in the underground Pyhäsalmi mine, Finland. Note that this is a conference abstract and that we have also published a longer peer-reviewed paper on the same topic. The latter's title is the same, but its authors are in a different order (Joutsenvaara...

It can be reasoned that many emerging scientific disciplines arise when the conventional sciences cross paths in a manner not seen before. Events like these may lead to the rapid development of new methodologies, concepts, and technologies as the collaboration between previously separate research communities forms a fruitful background to further d...

A poster in the meeting "Muographers 2021, International Workshop on Cosmic-Ray Muography, 24-26 November 2021, Ghent, Belgium."

The literature concerning muography has steadily increased in recent years, but so far very few publications have taken into account the true complexity of rocks in different locations. The same is also valid for the question of how deep underground muography can be applied. This work focuses on these topics and reviews the differences between cont...

Muography has applications in engineering, border control, tunnel detection, cave mapping, architecture, archaeology, volcanology, mineral exploration, mining, rock mechanics, water exploration, and many monitoring scenarios. This work will summarise the current development trends in muography by analysing the research publication data mined from t...

Meteorological-tsunami-like (or meteotsunami-like) periodic oscillation was muographically detected with the Tokyo-Bay Seafloor Hyper-Kilometric Submarine Deep Detector (TS-HKMSDD) deployed in the underwater highway called the Trans-Tokyo Bay Expressway or Tokyo Bay Aqua-Line (TBAL). It was detected right after the arrival of the 2021 Typhoon-16 th...

Muography uses muons naturally produced in the interactions between cosmic rays and atmosphere for imaging and characterization of density differences and time-sequential changes in solid (e.g. rocks) and liquid (e.g. melts±dissolved gases) materials in scales from tens of metres to up to a few kilometres. In addition to being useful in discovering...

This work proposes that cosmic-ray muography could be used in mineral exploration and resource delineation of skarn deposits as density variations between different skarn types and their immediate host rocks.

Tidal measurements are of great significance since they may provide us with essential data to apply towards protection of coastal communities and sea traffic. Currently, tide gauge stations and laser altimetry are commonly used for these measurements. On the other hand, muography sensors can be located underneath the seafloor inside an undersea tun...

A few minutes speed talk under the "Beyond 2021 - The Next Hundred Years" Technical Session of the SEG 100 Conference about how cosmic-ray muography could offer new opportunities in mineral exploration, planetary missions, and asteroid mining

A few minutes speed talk under the "Beyond 2021 - The Next Hundred Years" Technical Session of the SEG 100 Conference about how lunar in-situ resources can be explored by applying density sensitive cosmic-ray based geophysical muon imaging method called muography.

The water-ice deposits confined in the lunar regolith form a potential reservoir of water, hydrogen and oxygen for human settlements, scientific research, in-situ resource extraction, construction, and rocket propellants. Here we propose a concept of mobile lunar rovers that would operate as Muon Telescope Rovers (MTRs) in an attempt to apply muogr...

Atmospheric muons are formed in planets' atmospheres as a by-product of natural interactions between atmospheric nuclei and primary cosmic rays. On atmosphereless objects, the production of muons takes place directly in the uppermost layer of the solid object. This also happens on the lunar surface, as our earlier simulations indicate. We propose t...

Tidal measurements are of great significance since they may provide us with essential data to apply towards protection of coastal communities and sea traffic. Currently, the tide gauge stations, satellite-based, pressure-based and ultrasonic-based techniques are commonly used. However, with these techniques, sensors have to be either floated on the...

The novel geophysical remote imaging method of muography is based on cosmic-ray induced muon particles that are detected after passing through the media of interest. If the studied objects are solid, their sizes can vary from meters to up to kilometres. In underground tunnelling, muography has at least four applications: (1) muography can be used t...

Subsurface fracturing and weathering in bedrock are typically studied and imaged with conventional remote geophysical techniques. We introduce a new technique, muography, for carrying out such studies. This technique is based on the detection of atmospheric cosmic-ray induced muon particles after they pass through rock.

Callio Lab, the host of Callio SpaceLab, is a unique underground infrastructure located at the depths of the Pyhäsalmi mine, Finland. It is one of the cornerstones of the ‘Callio – Mine for business’ concept. The Callio concept aims to create and maintain an economically feasible environment for all mine re-purposing activities at the mine site. Th...

Meteorite impact structures can provide important information on long-term denudation on the Earth's cratons. Impact structures in the Fennoscandian Shield contain rocks (i.e., impactites), that have developed during the collision, and, possibly, remnants of the pre-impact sedimentary rocks. The crater depressions may also be filled with post-impac...

Muography is a novel geophysical imaging method for large solid objects and it maps relative density variations in 2D, 3D or 4D (density data + time analysis). In geothermal exploration, muography can be used, for example, for remote detection of faults and estimation of associated permeabilities. In the best-case scenarios, muography can be used t...

Crustal-scale faults deserve more attention as potential deep low-enthalpy geothermal energy sources in Finland. As well known, major structures may behave as favourable permeability channels for meteoric waters. They may also be characterised by elevated geothermal gradients, although the opposite is also possible. For Enhanced Geothermal System (...

In the present study, the novel geophysical imaging method of muography is introduced for the studies of rocks around scientific boreholes drilled into continental crust (or oceanic crust thrust over continental crust). In this application, the method can be used for detecting density variations in rocks intersected by the borehole. The present stu...

The Earth’s cratons are traditionally regarded as tectonically stable cores that were episodically buried by thin sedimentary covers. Cratonic crust in southern Finland holds seven post-1.7 Ga tiered unconformities, with remnants of former sedimentary covers. We use the geometries of the tiered unconformities, along with previously dated impact str...

Muography is a novel imaging method using natural cosmic-ray radiation for characterising and monitoring variation in average material density in a diverse range of objects that cannot be imaged by conventional imaging techniques. Muography includes muon radiography and muon tomography. Cosmic-ray-induced muons were discovered in the 1930’s, but ra...

The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. In this talk results from NBR measurements per...

In operating mines, as well as in deep locations for planned scientific activities, it is essential to recognize the natural background radiation from the point of view of both occupational hazard and experimental background. Callio Lab, located in the Pyhäsalmi Mine, Finland, is one of the underground laboratories participating in the Baltic Sea U...

Muography is a technique that produces density images of solid objects (or liquids within solids) by utilising detection of highly penetrative muon particles as they travel at relativistic speeds through the muon detector positioned behind the target of interest. Muography can be used as an independent method to determine the relative densities of...