Die Ortschaft St. Egidien wurde seit den 50er Jahren des 20. Jahrhunderts industriell durch die Verhüttung von Nickelerzen im VEB Nickelhütte St. Egidien geprägt. Relikt dieser Verhüttung ist das Gelände der Mineralwolledeponie, welches sich nördlich des heutigen Gewerbegebietes „Achat“ in St. Egidien an der neuen Umgehungsstraße „Achatstraße“ befindet. Im Zuge der Aufwältigung und Sanierung des Deponiekörpers kam es 2011 zur Verlegung neuer Entwässerungsrohre und zum Bau eines neuen Regenrückhaltebeckens. Die Verfasserin bekam die Möglichkeit, während SiGeKo-Begehungen Bau begleitend vom 14.05.2011 bis zum 02.09.2011 Fotodokumentationen während der Tiefbauarbeiten zu erstellen. St. Egidien ist seit Jahrhunderten für wunderschöne Jaspise und Achate bekannt, die bereits im Auftrag von Friedrich dem Großen in Kunst- und Alltagsgegenständen verewigt wurden. Während des aktiven Abbaus der Nickelhydrosilikate in den ortsnahen Tagebauen Callenberg Süd I und II sowie Callenberg Nord I und II kam es zufällig zu Funden großer Achatkugeln und Linsen bis zu 40 cm Durchmesser und größer. Deshalb wurde 1996 eine Bergung der Achatkugeln auf dem 'Westfeld' nördlich von St. Egidien durchgeführt. Die achathöffigen Gebiete verlaufen in einem durch sedimentäre und tektonische Prozesse unterbrochenen Streifen entlang dem Erzgebirgs-Becken (Rotliegend) von Zwickau bis nach Chemnitz. Die Form der Achate kann hierbei von Gängen über eine diskusartige Formen bis hin zu der charakteristischen Kugelform reichen. Viele Dokumentationen der Aufschlüsse des Rotliegenden gab es in der Vergangenheit in St. Egidien dazu nicht. In den Fotodokumentationen wurde der Baufortschritt der Tiefbauarbeiten während der Sanierung des nördlichen und nordöstlichen Bereichs der Mineralwolledeponie St. Egidien von Schacht Nr. 6 bis Schacht Nr. 1 der Reihenfolge nach dokumentiert. Es konnte die Planitz-Formation mitsamt dem achathöffigen Ignimbrit sowie die Härtensdorf-Formation dokumentiert werden. Die Ansprache der Lockergesteine erfolgte vorwiegend ingenieurgeologisch. Im neuen Regenrückhaltebecken wurde zudem der örtliche Ignimbrit lokalisiert und dokumentarisch festgehalten.:1. Veranlassung 2. Ausschnitt Lageplan Deponie mit Entwässerungsschächten 3. Fotodokumentationen der Sanierungsarbeiten 3.1 Fotodokumentation Begehung Randbereiche außerhalb Deponie St. Egidien 14.05.2011 3.2 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 16.05.2011 Bereich Schacht Nr. 5 3.3 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 17.05.2011 Bereich zwischen Schacht Nr. 5 und Schacht Nr. 4 3.4 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 18.05.2011 Bereich Schacht Nr. 5 3.5 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 20.05.2011 Bereich zwischen Schacht Nr. 5 und Schacht Nr. 4 3.6 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 24.05.2011 Bereich Schacht Nr. 4 3.7 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 27.05.2011 Bereich zwischen Schacht Nr. 4 und Schacht Nr. 3 3.8 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 10.06.2011 Bereich Schacht Nr. 2 3.9 Fotodokumentation Bau des Regenrückhaltebeckens auf der Deponie St. Egidien, 10.08.2011 3.10 Fotodokumentation Bau des Regenrückhaltebeckens auf der Deponie St. Egidien, 02.09.2011 4. Detailaufnahmen Profile 1 bis 3 4.1 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 27.05.2011 Schacht Nr. 4 bis Schacht Nr. 3: Profil 1 neben Verbau 4.2 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 27.05.2011 Schacht Nr. 4 bis Schacht Nr. 3: Profil 2 nahe Schacht Nr. 4 4.3 Fotodokumentation achathöffiger Aushub Deponie St. Egidien 10.06.2011 Bereich Schacht Nr. 2: Profil 3 Danksagung

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During the mid Cenozoic, the Chocolate Mountains region of southeastern California experienced crustal extension slightly before, during, and after the main pulse of magmatism. This combined with mid-late Cenozoic faulting to locally uplift plutonic rocks interpreted to represent the plumbing system(s) for volcanic units, allowing an examination of both the extrusive and intrusive result of magmatism. Zircon U-Pb ages of from six magmatic units yield late Oligocene to early Miocene ages and correlate better with stratigraphic relationships than previously compiled ages. These units are four silicic volcanic units – Quechan volcanic rocks, tuff of Felipe Pass, ignimbrite of Ferguson Wash, and tuff of Black Hills – and two plutonic units – the granites of Mount Barrow and Peter Kane Mountain. Regarding contemporaneous plutonic systems as baseline comparisons, zircons from the volcanic units commonly record plutonic temperatures; interpreted to be solidus or near solidus temperature. Remobilization may be a common process leading to eruption. Quartz and zircon thermometers reveal the ignimbrite of Ferguson Wash and tuff of Black Hills magmatic systems evolved differently. Quartz yields temperatures of 700°C to ~750°C in both units with no core-rim trends. Cores of zircons from the ignimbrite of Ferguson Wash yield temperatures between 750°C and 890°C. Zircon rim temperatures are between 875°C and 950°C. Tuff of Black Hills zircon cores generally record temperatures of ~850°C and zircon rim temperatures are ~700°C. Rims from tuff of Black Hills zircon record the same temperature range as zircons from coeval granites. The temperature increase from core to rim in zircons from the ignimbrite of Ferguson Wash indicates reheating and that zircon grew later than and at higher temperatures than quartz. The low zircon temperatures from tuff of Black Hills reveals a system that was growing quartz and zircon at the same low, nearly solidus temperatures. Reasons for its eruption are not readily apparent in the thermal history of zircon and quartz. These two systems record different thermal histories than previously studied, younger systems like the Bishop tuff, in which quartz records late reheating just prior to eruption and a system that was growing quartz later and at higher temperatures than zircon.

Development of homes, roads, and commercial buildings in northern Utah has grown significantly during the last several decades. Construction has expanded from the valley floor to higher elevations of benches, foothills, and other elevated regions of the Wasatch Mountain Front. Construction in the higher elevation areas are a concern due to potential for landslides, both new and reactivated. Landslides have been identified in this region and are dated as Pleistocene to historical in age. A possible landslide of about 0.5 km2 on the south slope of Traverse Mountain has been mapped by the Utah Geological Survey in 2005. Its surface exhibits hummocky topography and is comprised of Oligocene-age volcanic ash, block and ash flow tuffs, and andesite lava. Landslides along the Wasatch Mountain Front are complex features usually characterized by dense vegetation and poor outcrop and require a combination geological and geophysical methods to study their thickness, slope, lateral extent, and style of emplacement. Our study incorporates trenching, boreholes, and LiDAR aerial imagery. Unique to the study of landslides is our use of seismic reflection with a vibroseis source over the mapped landslide deposit. The seismic parameters of source, station spacing, and processing method provide a coherent, albeit low-resolution, image of the upper 500 m of the subsurface beneath the landslide. A major reflector boundary in our seismic profiles has an apparent dip of 4° to the south, approximately parallel with the surface topography. Its elevation and seismic character are indicative of a contact between the Oligocene-age volcanic rocks on top of a portion of the Pennsylvanian-age Bingham Mine Formation, a mixed carbonate and siliciclastic sequence. The reflector defines an asymmetric graben-like structure bounded by a north-northwest-trending normal fault system. Analysis of trenches, boreholes and local geology reveals a faulted, chaotic body of block and ash flow tuffs, surrounded by andesite lavas. Using LiDAR and surface geological reconnaissance, a possible toe or margin of a landslide has been interpreted in the north-west portion of the study area. The combination weakened block and ash flow tuffs and abundant clay production from this unit contribute to the likelihood of a coalescence of landslides in this mapped landslide area. The integration of LiDAR, trenching, boreholes and reflection seismology provides the range and resolution of data needed to assess the complex geology of landslides.

Betong är ett av världens mest använda byggnadsmaterial, men kan också vara en stor miljöbov. Cementklinker är en betydande beståndsdel i betong som vid tillverkning frigör stora mängder koldioxid, av den anledningen optimeras betongrecept idag genom att ersätta en del av cementen med flygaska som är en restprodukt från kolkraftsindustrin. I takt med att samhället rör sig mot en fossilfri produktion beräknas tillgången till flygaska att avta och material med liknande egenskaper undersöks som alternativa bindemedel i betong.  Syftet med studien är att, genom litteraturstudier och laboratoriska tester, undersöka huruvida naturliga puzzolaner kan ersätta mängden flygaska i en cementsammansättning utan att försämra betongens hållfasthetsegenskaper. Tryckhållfastheten samt hållfasthetsutvecklingen har undersökts hos 150x150x150 mm provkuber med varierande mängd flygaska samt vulkanaska av isländsk pimpsten respektive jordanska tuffer. Målet med studien är att minska mängden, eller helst ersätta hela andelen flygaska i en klimatförbättrad betongsammansättning.  De laboratoriska testerna har utförts enligt svensk standard där totalt 48 provkroppar gjutits. Referenskuben i undersökningen består av 80% portlandkalkstencement och 20% flygaska. Totalt har 6 olika kombinationer av provkuber gjutits där andelen flygaska ersätts med 20%, 15% eller 10% vulkanaska. Vardera provkub har utsatts för tryckhållfasthetsmätning efter 2, 7 samt 28 dygn.  Resultatet av provtryckningen visade att provkuberna innehållande isländsk pimpsten gav en ökad eller oförändrad hållfasthet vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande jordanska tuffer medförde däremot en reducering av hållfastheten vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande vulkanaska från isländsk pimpsten gav högst sluthållfasthet då ingen flygaska förekom i sammansättningen och något sämre värden vid inblandning av flygaska, till skillnad från provkuberna innehållande vulkanaska från jordanska tuffer som utan flygaska i princip stannade av i sin hållfasthetstillväxt efter 7 dygn. Skillnaden i resultatet mellan vulkanaska av pimpsten respektive tuffer antyder att vilken typ av material det är samt dess ursprung har betydelse för hur det presterar som bindemedel i betong. / Concrete is one of the most widely used building materials in the world, but it can also be a major environmental culprit. Cement clinker is a significant component of concrete that releases large amounts of carbon dioxide during production. For this reason, concrete recipes are now optimized by replacing some of the cement with fly ash, which is a byproduct from the coal power industry. As society moves towards fossil-free production, the availability of fly ash is expected to decrease, and materials with similar properties are being investigated as alternative binders in concrete.  The purpose of the study is to investigate, through literature review and laboratory tests, whether natural pozzolans can replace the amount of fly ash in a cement composition without deteriorating the strength properties of the concrete. The compressive strength and strength development have been studied on 150x150x150 mm test cubes with varying amounts of fly ash and volcanic ash from Icelandic pumice and Jordanian tuffs. The goal of the study is to reduce the amount, or preferably replace the entire portion, of fly ash in a climate-improved concrete composition. The laboratory tests have been performed according to Swedish standards, where a total of 48 test specimens have been cast. The reference cube in the study consists of 80% Portland limestone cement and 20% fly ash. A total of 6 different combinations of test cubes have been cast, where the proportion of fly ash is replaced with 20%, 15%, or 10% volcanic ash. Each test cube has been subjected to compressive strength measurement after 2, 7, and 28 days. The results of the compression testing showed that the test cubes containing Icelandic pumice provided increased or unchanged strength at all measurements, compared to the reference cube. However, the test cubes containing Jordanian tuffs resulted in a reduction of strength at all measurements, compared to the reference cube. The test cubes containing volcanic ash from Icelandic pumice provided the highest final strength when no fly ash was present in the composition, and slightly lower values when fly ash was added, unlike the test cubes containing volcanic ash from Jordanian tuffs which essentially plateaued in their strength development after 7 days without fly ash. The difference in results between volcanic ash from pumice and tuffs suggests that the type and origin of the material are significant factors in how they perform as a binder in concrete.

A belt of Early Proterozoic rocks crops out in the Cottonwood Cliffs area, northwest Arizona. The belt contains an eastern and a western assemblage separated by the Slate Mountain fault. The western assemblage consists of mafic to felsic metavolcanic rocks, metapelites, and metaconglomerates. The eastern assemblage consists of phyllites, felsic to intermediate metavolcanic rocks, metagraywackes, and metagabbro bodies. The belt is bounded to the east by foliated granodiorite. The Valentine granite intruded the belt on the west and north. Steeply-plunging lineations and fold axes, and northeast-trending vertical foliation dominate the structural fabric. The regional elongation direction is near-vertical, as indicated by mineral and pebble lineations, and is parallel to fold axes. Although only one deformational event is evident, the intensity of that event may have obliterated evidence of any earlier deformation. Tertiary basalts and the Peach Springs Tuff locally overly the metamorphic rocks. Cenozoic normal faults in the area are mostly of minor displacement.

As part of the wider European GTS Next project, I propose new constraints on the ages of the Late Cretaceous, derived from a multitude of geochronological techniques, and successful stratigraphic interpretations from Canada and Japan. In the Western Canada Sedimentary Basin, we propose a new constraint on the age of the K/Pg boundary in the Red Deer River section (Alberta, Canada). We were able to cyclostratigraphically tune sediments in a non-marine, fluvial environment utilising high-resolution proxy records suggesting a 11-12 precession related cyclicity. Assuming the 40Ar/39Ar method is inter-calibrated with the cyclostratigraphy, the apparent age for C29r suggests that the K/Pg boundary falls between eccentricity maxima and minima, yielding an age of the C29r between 65.89 ± 0.08 and 66.30 ± 0.08 Ma. Assuming that the bundle containing the coal horizon represents a precession cycle, the K/Pg boundary is within the analytical uncertainty of the youngest zircon population achieving a revised age for the K/Pg boundary as 65.75 ± 0.06 Ma. The Campanian - Maastrichtian boundary is preserved in the sedimentary succession of the Horseshoe Canyon Formation and has been placed ~8 m below Coal nr. 10. Cyclostratigraphic studies show that the formation of these depositional sequences (alternations) of all scales are influenced directly by sea-level changes due to precession but more dominated by eccentricity cycles proved in the cyclostratigraphic framework and is mainly controlled by sand horizons, which have been related by autocyclicity in a dynamic sedimentary setting. Our work shows that the Campanian - Maastrichtian boundary in the Western Canada Sedimentary Basin coincides with ~2.5 eccentricity cycles above the youngest zircon age population at the bottom of the section and ~4.9 Myr before the Cretaceous - Palaeogene boundary (K/Pg), and thus corresponds to an absolute age of 70.65 ± 0.09 Ma producing an ~1.4 Myr younger age than recent published ages. Finally, using advances with terrestrial carbon isotope and planktonic foraminifera records within central Hokkaido, Northwest Pacific, sections from the Cretaceous Yezo group were correlated to that of European and North American counterparts. Datable ash layers throughout the Kotanbetsu and Shumarinai section were analysed using both 40Ar/39Ar and U-Pb methods. We successfully dated two ash tuff layers falling either side of the Turonian - Coniacian boundary, yielding an age range for the boundary between 89.31 ± 0.11 Ma and 89.57 ± 0.11 Ma or a boundary age of 89.44 ± 0.24 Ma. Combining these U-Pb ages with recent published ages we are able to reduce the age limit once more and propose an age for the Turonian - Coniacian boundary as 89.62 ± 0.04 Ma.

The Green River Formation was deposited between 53.5 and 48.5 Ma. The Angelo, Fossil Butte, and Lower members of the Green River Formation at Fossil Basin, preserve ash fall tuffs deposited in ancient Fossil Lake. 40Ar/39Ar dating of sanidine yielded eruptive ages of 51.29 ± 1.29 Ma and 52.20 ± 3.08 Ma for two of the tuff beds within Fossil Basin. Immobile element and mineral compositions of Fossil Basin tuffs indicate that most tuffs erupted from a subduction zone originally as rhyolites and dacites. X-ray diffraction analyses reveal that the tuffs' glassy matrices have been altered to illite, calcite, clinoptilolite, analcime, albite, and K-feldspar. The variable alteration of the tuff beds confirms previous studies of Fossil Lake's salinity fluctuation through time. One outcrop (FB-10), which was previously interpreted to represent the K-spar tuff, has biotite of different compositions from that in known K-spar tuff samples (FB-09 and FB-11). Tuff horizons from the Greater Green River Basin have feldspar and biotite compositions similar to those from tuffs in Fossil Basin and are interpreted to have the same eruptive sources. Based on age and proximity, the Absaroka and Challis volcanic fields are the likely sources of tephra deposits in Fossil Basin and the Greater Green River Basin. Calc-alkaline tephras in these lacustrine basins have similar magmatic characteristics to the tuff of Ellis Creek (48.4 ± 1.6 Ma) from the Challis volcanic field. However, major and trace element, and mineral compositions of Absaroka and Challis volcanic rocks are not distinctive enough to definitively determine the source of most Fossil Basin and Greater Green River Basin tephras. Two samples, FB-10 from Fossil Basin and WN-79.15 from the Greater Green River Basin, have compositions similar to calc-alkaline magmas, but have some mineral compositions with A-type chemical affinities; consequently we conclude that they were erupted from volcanoes within the Challis volcanic field. Compositions of Challis volcanic rocks may have important implications for the development of a slab window in western North America during the Eocene. Compositional variation of Challis volcanic rocks through time indicates that calc-alkaline rocks with a slight A-type component erupted early in its history, and as the slab window matured the Challis volcanic field dominantly erupted rocks with a more A-type chemical affinity. A slab window may have developed due to the Farallon slab subducting at a shallow angle beneath the North American plate, and gravity may have caused it to break to the north. Through time the slab could have torn to the south and by 50 Ma the slab window would have been opening beneath the Challis volcanic field. This would have erupted calc-alkaline magmas, but upwelling of the asthenosphere into the mantle wedge (beneath the North American plate) would have introduced A-type magmatism into the magmatic system. By 45 Ma, the slab would have matured and opened sufficiently beneath the Challis volcanic field to replace calc-alkaline magmatism with, first "transitional" magmatism, and then A-type magmatism as evident in the youngest Challis tuffs.

Indiana University-Purdue University Indianapolis (IUPUI) / The Antler and Sonoma orogenies occurred along the southwest-trending passive Pacific margin of North America during the Paleozoic concluding with the accretion of the McCloud Arc. A southeast-trending sinistral transform fault truncated the continental margin in the Permian, becoming a locus for initiation of an east-dipping subduction zone creating the Sierran magmatic arc. Constrained in age between two early Triassic tuff layers, the volcanic clasts in the breccia of Frog Lakes represent one of the earliest records of mafic magmatism in the eastern Sierra Nevada. Tholeiitic rock clasts found in the breccia of Frog Lakes in the Saddlebag Lake pendant in the east central Sierra Nevada range in composition from 48% to 63% SiO2. Boninites produced by early volcanism of subduction initiation by spontaneous nucleation at the Izu-Bonin-Mariana arc are more depleted in trace element concentrations than the clasts while andesites from the northern volcanic zone of the Andes produced on crust 50 km thick have similar levels of enrichment and provide a better geochemical modern analogue. Textural analysis of the breccia of Frog Lakes suggest a subaqueous environment of deposition from a mature magmatic arc built on continental crust > 50 km thick during the Triassic. The monzodiorites of Saddlebag and Odell Lakes are temporal intrusive equivalents of the breccia of Frog Lakes and zircon geochemistry indicates a magmatic arc petrogenesis.