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As a part of Kumpula Campus Drill Hole Project, a 370 m deep drill hole was drilled on the University of Helsinki, Kumpula campus area in December 2015. Drilling took place on an amphibolitic outcrop, which is the main rock type of the area and part of the 1.9 Ga old Svecofennian orogenic belt. In this work, the geochemistry of the campus bedrock is analyzed, focusing on the amphibolite. Granite, actinolite rock and diopside-actinolite skarn are additional rock types described from the core in this work. The geochemical methods utilized are a portable X-ray fluorescence (P-XRF) spectrometer Niton XL3t GOLDD+ by Thermo Scientific and a laboratory wavelength dispersive X-ray fluorescence (WD-XRF) spectrometer PANAlytical Axios mAX 4kW. WD-XRF device is utilized in quantitative analysis and semi-quantitative Omnian scans. In addition to geochemical interpretation of the bedrock, feasibility of the P-XRF device in outcrop and drill core related studies is evaluated by comparing the methods. The surface of the drill core was analyzed with the P-XRF device. Representative samples of each rock type were sawed of the core and analyzed with both P-XRF and WD-XRF Omnian scans. In addition to surface analyses, a fused bead was prepared from one representative amphibolite sample and analyzed with WD-XRF quantitative method. Outcrop studies focused on the feasibility of the P-XRF device in in situ analyses. Compared to nearest temporally related amphibolite units, the amphibolite of the campus bedrock seems to be more felsic on average. All described rock types are connected to former petrogenetic interpretations of the local bedrock. However, further geochemical analyses are required to verify the interpretations. WD-XRF quantitative method and Omnian scans suggest almost similar results for fused bead of the amphibolite. Changing the sample type to solid rock surface introduces heterogeneity related problems to the quantitative determination of Omnian scans and quality of the results decreases almost to the level of P-XRF. Yet, the advantage of the Omnian scans method in rock surface analyses compared to P-XRF is better detection of light elements. For example, P-XRF device detects Mg, Al and K poorly and Na is not detected at all. On the other hand, SiO2 is on average detected quite accurately from rock surface with P-XRF when compared to WD-XRF quantitative method for fused bead. WD-XRF Omnian scans and quantitative application results of fused bead do not seem to differ remarkably. Broad rock type classification can be made with P-XRF device for drill core, but results cannot be considered quantitative. It should also be noticed, that the major element oxide sum values of P-XRF drill core surface analyses are quite low on average (84.00 wt.%). In outcrop analyses, different features lower the quality of the rock surfaces, resulting in even lower major element oxide sum values in analysis. Although major oxide sum values are very low on outcrops, relatively high amounts of for example Cl, S and P are detected for unknown reasons. Major advantages of the P-XRF device are the ease of use, light weight and rather good detection of for example SiO2. Developing the quantitativeness of the device would make it more comparable to laboratory XRF devices but it already has multiple features that are highly beneficial in a wide range of scientific fields.

The Central Finland Granitoid Complex (CFGC) is a large (44,000 km2) plutonic core of a Svecofennian (Paleoproterozoic, 1.91–1.82 Ga) arc complex, formed from collisions of several volcanic arcs and their accretion over the Karelian craton. The CFGC consists mostly of granitic to granodioritic rock types. Mafic-ultramafic plutonic rock types are not common, and they consist of mostly small gabbro-diorite intrusions, which may have ultramafic parts. There are two distinct belts around the CFGC, where Ni-Cu potential mafic-ultramafic intrusions are situated – Vammala and Kotalahti. The intrusions within these belts were formed during the height of magmatism within the CFGC (1.89–1.87 Ga). They host Ni-Cu mineralizations, some of which have been economically exploited. The mineralizations are hosted by olivine-rich ultramafic cumulates. The intrusions formed from hydrous tholeiitic basalts (10–12 wt-% MgO) with arc-type trace element chemistry. The difference between Vammala and Kotalahti type intrusions (clinopyroxene and orthopyroxene-dominated, respectively) are attributed to the rock type of the assimilated country rock. In this thesis, three previously unknown or poorly studied mafic-ultramafic intrusions (Matokulma, Palojärvi, and Hongonniittu) within the CFGC are studied in detail. The petrology, similarity to Vammala-Kotalahti type intrusions, parental magma compositions, ore potential, and petrogenesis of the intrusions are described. Rock samples and field observations were gathered during the summer of 2017. Whole-rock geochemistry, mineral geochemistry, isotope geochemistry, and geophysics are used to describe the petrology of the intrusions. Matokulma and Palojärvi intrusions are studied in detail, compared to Hongonniittu intrusion, which was not studied as intricately. The Matokulma intrusion is the least evolved (whole-rock median Mg#=72) of the studied intrusions and consists of tholeiitic melagabbros where clinopyroxene±orthopyroxene and plagioclase are the main cumulus phases within interstitial, magmatic amphibole (magnesiohastingsite to pargasite in composition). Orthopyroxene and plagioclase are intercumulus phases in some samples. There are also mafic dikes that intrude the tonalitic country rock that surrounds the gabbro. The dikes are similar to the gabbros in geochemistry although they are generally more evolved. Trace element geochemistry suggests that the gabbros and dikes are genetically connected, and the dikes possibly represent the residual magmas of the gabbros. The Palojärvi intrusion is noticeably more evolved than the Matokulma intrusion (median Mg#=49), which is apparent in the iron and titanium rich mineral and whole-rock geochemistry. The strongly tholeiitic melagabbros are composed of both orthopyroxene and clinopyroxene as cumulus phases with plagioclase and common Fe-Ti oxide, often within interstitial magmatic amphibole (magnesio-hastingsite to magnesioferri-hornblende in composition). The Fe-Ti oxides are mostly ilmenomagnetite but both magnetite and ilmenite grains are present in same samples. Based on a few mineral analyzes, the ilmenomagnetite contains up to 1.4 wt-% V2O3. U-Pb age determination samples from a leucogabbro dike within the intrusion and granite that crosscuts the intrusion yielded weighted average 206Pb/207Pb ages of 1883.4±4.8 Ma and 1893.8±7.1 Ma, respectively. The age results are in contrast to the intrusive relationship observed in the field. However, considering the margin of error of the results, the granite can be younger than the gabbro, 1887 Ma and 1888 Ma, respectively. The age of ca. 1.89 Ga is at the early stage of the most voluminous mafic-ultramafic magmatism in the Svecofennian terrane. The parental magmas of the Matokulma and Palojärvi intrusions were evolved and contained approximately 5 wt-% and 2 wt-% MgO, respectively. The presence of magmatic amphiboles in most samples indicate that the parental magmas were hydrous. Samples from all intrusions plot similarly in primitive mantle normalized Rare Earth Element (REE) and Normal-Mid-Ocean Ridge Basalt (NMORB) normalized spider diagrams. Similar patterns indicate a similar source for the parental magmas. The trace element geochemistry has signatures of subduction related fluid metasomatism. The rocks are enriched in large ion lithophile elements (LILE) and depleted in High Field Strength Elements (HFSE). These geochemical characteristics indicate that the studied intrusions crystallized from a hydrous, NMORB-like evolved basaltic magma, which has experienced fluid metasomatism. The studied intrusions differ from olivine-rich ultramafic cumulates of Vammala and Kotalahti type intrusions based on their more evolved, gabbroic composition and because of this, they are not Ni-Cu ore potential. Palojärvi may host a Fe-Ti-V mineralization, if there are magnetite rich layers within the intrusion.

Glaciers and ice caps (GICs) excluding Greenland and Antarctic ice sheets account for large proportion of potential future sea level rise and are losing great amount of their mass in high confidence by 2100. Glacier elevation change observations covering whole Greenland’s GICs are limited to the 21st century and regional geodetic mass balance estimates are scarce. Recent development of photogrammetric software and rediscovery of old aerial photographs has been increasingly used to extend temporal resolution of glacier change studies. Besides for extended mass balance observations, historical photographs may be used in observing glacier surge events to improve their coverage in glacier inventories. In this study, 320 historical aerial photographs from 1953/1954 were photogrammetrically processed to create new digital elevation model (DEM) of the 1953 surface. Comparing the 1953 DEM with 1985 and 2016 DEMs extended the geodetic mass balance records on Nuussuaq peninsula to 63 years. Moreover, differenced DEMs were used with orthophotomosaics to identify glacier surface changes and advances and their possible relation to glacier surges. The study also explored the usage of Open Global Glacier Model (OGGM) with user defined input data for simulating future glacier changes in small scale regional setting. The geodetic mass balance results showed clear change from near equilibrium mass balance in 1953-1985 to overall mass loss in 1985-2016. Glacier surface lowering was found to shift to higher elevations along with the change to negative mass balance and occurred throughout the elevation range in 1985-2016. In contrast to generally retreating glaciers, advancing and/or surface elevation increases at the glacier fronts with glaciomorphological evidence of surging were observed on 5 glaciers. OGGM model is easily applicable for smaller regions but correcting the OGGM calibration with a fit to the geodetic mass balance data didn’t provide explicit result of the re-calibration efficiency. Historical photographs provide source to extend geodetic mass balance estimates and means to observe past glacier changes in more detail. Therefore, their incorporation in glacier change studies should be continued and create consistent datasets over larger regions. More research is needed with additional reference data to assess the reliability of the OGGM performance on a region without the reference data from default reference glacier network and the effect of re-calibrating with geodetic fit.

Tavoitteet. Tutkimuksen tavoitteena on selvittää, kuinka paljon yhdeksännen luokan matematiikan valtakunnallisia kokeita tulisi muuttaa, mikäli GeoGebra hyväksyttäisiin työvälineeksi kokeeseen. Kouluissa jatkuvasti käytetään yhä enemmän tietokoneita ja ohjelmistoja. Ylioppilaskokeet ovat sähköistyneet. On siis tärkeää kartoittaa, kuinka paljon valtakunnallisia kokeita pitäisi muuttaa, mikäli koe sähköistyisi tulevaisuudessa. Aiemmat tutkimukset ovat osoittaneet, että GeoGebra parantaa oppimistuloksia, asenteita ja motivaatiota matematiikan opiskelussa. Kuitenkin on havaittu, että tarpeeksi haastavien tehtävien suunnittelu GeoGebralle on haastavaa sekä joidenkin komentojen syöttämistapa on vaikea oppilaille. Tässä tutkimuksessa lisäksi pohditaan, miltä osin osaaminen kehittyy ja toisaalta heikkenee, kun käytetään GeoGebraa tehtävien ratkaisemisessa. Menetelmät. Tutkimuksessa tutkittiin kvalitatiivisesti ja kvantitatiivisesti vuosien 2012–2021 matematiikan valtakunnallisten kokeiden laskimellisia tehtäviä. Laadullisesti esitettiin joidenkin tehtävien ratkaisuja GeoGebra ohjelmistolla. Tutkimuksessa pohditaan, riittääkö oppilaan taidot realistisesti ratkaisemaan tehtäviä esitellyllä tavalla. Määrällisesti selvitettiin, kuinka suuri osa tehtävistä toimisi sellaisenaan GeoGebraa käyttäen. Tulokset ja johtopäätökset. Yli puolet tehtävistä tulisi muuttaa, jos GeoGebra sallitaan välineeksi kokeeseen. GeoGebra heikentää mekaanisen laskutaidon kehittymistä, mutta kasvat-taa muun muassa visualisointitaitoja. Laskimellisessa osassa kannattaa painottaa ratkaisun muita osia kuin mekaanisia laskuvaiheita kuten yhtälönratkaisua. Laskimettomassa osassa voidaan testata mekaaninen laskutaito.

Ylioppilaskokeiden siirtyminen täysin sähköiseksi vuonna 2019 on tuonut merkittävän muutoksen matematiikan oppitunneille. Teknologia on tullut verrattain nopeasti hyvin olennaiseksi työvälineeksi osaksi matematiikan oppitunteja. Yksi käytetyimmistä ohjelmistoista matematiikan oppitunneilla Suomessa on dynaamisen matematiikan ohjelmisto GeoGebra. Tässä tutkimuksessa pohditaan GeoGebran vaikutusta matematiikan oppimiseen ja opetukseen. Tarkoituksena on selvittää, mitä tutkimukset havaitsevat, kun GeoGebralla on korvattu perinteistä opetusta matematiikan oppitunneilla. Tarkastellaan ohjelmiston soveltuvuutta kriittisestä näkökulmasta huomioimalla myös sen tuomat haasteet opetukseen ja oppimiseen. Lisäksi pohditaan, miten sovelluksella voidaan tukea oppijoiden kokemia haasteita etenkin geometriassa keskittymällä erityisesti sen soveltuvuuteen ”mittakaava”-käsitteen opettamisessa. Visualisoinnin ja teknologian voidaan nähdä hyvin keskeisenä osana matematiikan oppimista ja ajattelutaitojen kehitystä. Tutkimuksista havaitaan, että GeoGebran käyttö oppitunnilla toi parempia oppimistuloksia verratessa niitä luokkiin, joissa opetus toteutettiin perinteisellä tavalla. GeoGebran hyötynä nähdään erityisesti sovelluksen monipuolinen ja selkeä käytettävyys, matematiikan osaamisen vahvistaminen, oppimistaitojen tukeminen, ja motivaation lisääntyminen. Ohjelmiston käyttö ei kuitenkaan suoraan takaa menestystä matematiikassa, vaan siihen vaikuttaa suuresti opettajan osaaminen ja käyttö hyödyntää teknologiaa työvälineenä oppitunneilla. Tutkimuksissa tuodaan esiin keskeisenä kehityksen kohteena opettajien ongelmaratkaisutaitojen, palautteen antamisen ja teknologispedagogisen sisältötiedon tukeminen.

A growing number of researchers, including geographers, have under the last decades become interested in sustainability transitions. This thesis highlights the connections between geography and transitions in three ways: by critically analysing current models, by developing the geographical approach to transitions and by introducing methodological approaches for further studies. I go through three models that try to explain transitions, but choose to focus on the deep transition framework that describes establishment of meta-rules that steer long-term development beyond specific socio-technological systems and across spatial boundaries. This framework is however lacking a profound understanding of geography, which is why I go into how territories, places, scales and networks connect to transitions. I also discuss power as a geographical phenomenon and the governance of sustainability on a global level. There are signs that the United Nation’s vision of sustainability, has gained popularity in different institutions. I believe researchers should explore these signs further. Based on the theoretical framework, I show three different but complementary approaches for studying and interpreting strategies for societal development. I hope that the theoretical and methodological contributions this thesis gives will be utilized in further research on highlighting the connections between geography, sustainability, transitions and governance.

A vast amount of spatio-temporal data has become available with the fast development of information technology and different monitoring systems over the last two decades. Position-aware devices are one of the most dominant sources for collecting movement data. Spatio-temporal information that is derived from the tracking devices enable to build movement patterns from the targets, and to calculate measurable motion parameters such as speed, change of speed or the direction of movement. This study utilized a specific pilot GPS-based monitoring system called Amazonian Riverboat Observation System (AROS) that was built to collect movement data of the local riverboats on the departments of Loreto and Ucayali in Peruvian Amazonia. AROS provides real-time GPS-data with coordinates and timestamp that indicate where and when the collaborating vessels are navigating. As an outcome of this thesis a specific analytical tool called Trajectory Reconstruction and Analysis Tool (TRAT) was developed. TRAT utilizes variety of geographic knowledge discovery methods to extract knowledge from movement data provided by AROS. Also spatio-temporal transportation characteristics in the study area were analyzed based on AROS data from the year 2012 and utilizing TRAT. This thesis focused on studying if there is seasonal and directional variation in transportation characteristics along the Amazonian rivers, and if river morphology affects the navigation. Also connection between water height of the rivers and travel speed of individual journeys was studied. Results of the thesis suggest that navigation along the rivers has seasonal and directional variation, and also the river morphology seems to affect the movement patterns of the vessels. On navigation route that was mostly meandering by river morphology, the downstream navigation was over 40% faster than upstream navigation during high water and intermediate, but during low water there was no difference between navigation directions. Seasonal variation was over 30% faster during high water compared to low water (on downstream direction). On upstream direction the navigation was fastest during low water but seasonal differences were considerably lower compared to downstream navigation. On navigation route that was mostly anastomosing by river morphology, the downstream navigation was approximately 20 % faster during the entire year. Results suggest that there is no seasonal difference in navigation characteristics along the larger and wider rivers, since the travel speeds were quite similar throughout the year. Fitting simple regression model between average travel speed of the journeys and water levels of the river revealed that there seems to be strong connection between travel speed and river height on the route along Ucayali river when travelled downstream (R2=0.73). On other cases that were studied, the results suggest that there is not connection between travel speed characteristics and river height. Comparing the results with earlier studies implied that the results of this thesis seemed to be fairly accurate. However, it is necessary to validate the results by doing cross-validations between data from different years observed with AROS. Transportation is in a key role when trying to find the factors affecting on development of a certain location. Thus transportation as means of accessibility has significant role in variety of contexts such as conversation, land use changes and deforestation. Results of this study could provide more accurate data for studies focusing on previously mentioned topics in the study area. Also utilization of TRAT in other contexts, such as studying global transportation patterns of professional vessels, could be possible by making few modifications to the tool.

The geology of the Eastern Lapland Archean domain (the sudy area of this study) is vaguely known due to high metamorphism and poorly exposed lithologic assemblages. Three new U-Pb age determinations from key locations aim for more profound understanding of the geochronology of the area. Cu-Fe-S stable isotope data for copper sulfides from the Eastern Lapland Archean domain are presented for the first time. The stable isotope analytical method for Cu-Fe-S isotopes is refined and its applicability as a proxy for magmatic Ni-Cu-PGE sulfide deposits is evaluated. It has been suggested that, within an individual mineralized intrusion, negative correlation of δ34S and δ65Cu might be a useful indicator of the economic potential of Ni-Cu-PGE sulfide deposits. Combined S and Fe isotope systematics have also been used to fingerprint for the origin of sulfur. Three new samples were dated using the LA-ICP-MS method on zircon. Most of the Pultoselkä granite data are concordant and yield an age of 2795 ± 6 Ma. The data from the Kontioselkä pegmatite are mostly discordant and define maximum age for the pegmatite at 1766 ± 36 Ma. The Janesselkä gabbro yields an minimum age of 2425 ± 17 Ma, consistent with the 2,4–2,5 Ga age group of mafic magmatism observed widely across the Fennoscandian shield. The established U-Pb data imply distinct metamorphic effects during the Svecofennian and Caledonian orogenies. 28 stable isotope (Cu-Fe-S) data sets were measured from dissolved samples utilizing MC ICP-MS. A micro drilling method was used to extract sulfide cores for the solution work. Collectively the δ65Cu values of analysed sulfides (n = 28) range from -4,65 to 0,29‰, δ56Fe values from -0,21 to 1,44‰, and δ34S values from -1,38 to 11,77‰. Isotope values from magmatic sulfides (n = 7, 2σ) have a restricted range and distinct mean δ65Cu value of -0,99 ± 0,21‰, mean δ56Fe value of 0,16 ± 0,23‰, and mean δ34S value of 2,08 ± 0,3‰, consistent with chondritic compositions. The variation of isotopic values reflects the composition of the sulfide. Overall, they reflect varying crystallization histories and subsequent modification of the samples examined.

The Finnish spent nuclear fuel repository is currently under construction by Posiva Oy, and the repository will be located in Olkiluoto Island, western Finland. After intensive research of the site from surface drillholes, construction of underground rock characterisation facility named ONKALO began in 2004 in the same location for the purposes of detailed site characterization. Additionally, to ONKALO and research drillholes, 58 deep drillholes provide a large database for the geological, geochemical, geophysical and rock mechanics site characterisation. One of the key aspects of rock mechanics site characterisation is to determine the in situ stress field prevailing at Olkiluoto. Mathematically, the stress field is represented as a tensor with both direction and magnitude. The effect of excessive magnitudes of the tensor can be manifested by oriented fractures on the walls of the drillholes forming a phenomena of borehole breakouts along the drillhole length. The breakouts form when compressive stress, induced by the concentration of the in situ stress around the drillhole, exceeds the rock strength. The breakouts occur on the opposite sides of the walls. Due to the breakouts occurring in the areas of maximum compression around the drillhole walls, both the direction of the minimum (σh) and maximum (σH) horizontal in situ stress components can be inferred along the drillhole. This Master's thesis was set to identify and map the breakouts in the deep drillholes in Olkiluoto using the acoustic and optical imaging data of the deep drillholes. Acoustic and optical televiewers are two of the several geophysical measuring methods used in the drillholes. They produce images of the walls of the drillholes by wave reflection. During the study, different types of breakouts were identified along the drillholes in Olkiluoto: dotted, zipper-like and a mix of the two previous types with different intensities. The locations of the identified breakouts and other features (direction of σh, rock type, foliation) were recorded in a mapping form developed during this work. The mapping results show that in the total of 19 imaged drillholes, 40 breakout sections exist in only 5 drillholes. Geophysical data show that the breakouts are highly dependent on the geology and the majority of the breakouts occur in veined gneiss and in less competent rock types such as deformed or fractured rocks. Most of the breakouts were observed below 600 meters depth. Major group of directions of calculated σH from the mapped breakouts is oriented NE-SW (60-90°/245-270°) and secondary groups are oriented 107-150°/285-325° and 10-40°/190-220°. In some drillholes, the directions are rotated about 40° due to a significant brittle fault zone separating the site of Olkiluoto into stress field domains.

The Sukseton area is located in the northern part of Kittilä municipality, Central Lapland Greenstone Belt, approximately 15 km N from Suurikuusikko gold mine and 5 km NW from Iso-Kuotko orogenic gold deposit, between several large crustal scale thrust and shear zones. This area is a mix of different volcanic formations of Kittilä suite, felsic intrusion of Vuotso Complex and Paleoproterozoic intrusive rocks in the north. In addition to this, several porphyry dykes cut the Kittilä suite volcanic rocks around the area. Exploration work in this area started in the 1980’s when Outokumpu Oy found two minor gold and gold-copper mineralizations. In 2017, Agnico Eagle Finland Oy continued exploration in this area, intending to define the regional geology and the extent of the mineralizations. As a result of this exploration work, this study investigates more closely the regional geology, geochemistry, metamorphism and structural geology of the Sukseton area, as well as the geochronology of associated porphyry dykes. To understand and define the geology of the area, the following methods were used: geological bedrock and exploration trench mapping, interpretation of drill core loggings and several geophysical surveys, optical studies of polished thin sections and U–Pb dating a porphyry dyke sample. The metamorphic conditions of the area were studied through thorough petrological studies. In addition, an extensive geochemical and geotectonic classification of the rocks in the area was conducted. The Sukseton area composes mainly of different tholeiitic basalts and pyroclastic rocks with minor sulphide rich graphitic volcanic sediment and chert sections. Based on this study, these volcanic rocks originate from island arcs and mid-ocean ridges. With the help of geophysical surveys and field measurements, a couple of large fold structures were identified from the eastern part of the study area as well as a large shear zone in the middle of the area striking NE–SW. Porphyry dykes cut the volcanic rocks all around the area giving the minimum age of 1940±18 Ma for the volcanic rocks. Composition of porphyry dykes vary from rhyolites to basalt and they have similar geochemical characteristics with Nyssäkoski type felsic veins. The peak metamorphic conditions in the area represent high-P amphibolite facies metamorphism. Also, hydrothermal alteration is common in Sukseton and it can be metamorphic and magmatic in origin.