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Petrology of Pliocene (?) Basalts of Curlew Valley (Box Elder Co.), UtahKerr, Steven Brent 01 May 1987 (has links)
Basalt outcrops in Curlew Valley consist of vii several flow remnants and eruptive centers situated along the valley margins. Basalt is also found in association with salic rocks that erupted in the central portion of The basalts are of probable Pliocene age and the valley. were erupted during a period of active extensional tectonics. Since their emplacement, and downfaulted. the basalts have been extensively eroded The present morphology reflects the erosional and depositional processes of prehistoric Lake Bonneville.
Twelve samples were analyzed chemically for major oxides, trace elements, and rare-earth elements. The basalts form a hypersthene normative series ranging from olivine tholeiite to tholeiite. Based on chemical data, the basalts form three distinct groups. Comparison of the major oxides shows two of the groups forming a differentiation sequence separate from the third group. Trace element and rare-earth element data indicate that the three chemical groups are related to a common source but that two batches of magma probably emanated from this source.
Pyrolite, spinel lherzolite, and garnet lherzolite were evaluated as hypothetical mantle materials from which a parent magma might be derived through partial melting. Based on rare-earth element profiles, garnet lherzolite appears to be the most likely source material for deriving the basalts. The trace element and rare-earth element data do not show any anomalies that would suggest contamination from crustal material.
Comparison of chemical data shows that the Curlew Valley basalts are genetically similar to basalts from the Kelton and Rozel Point-Black Mountain areas, southwest and southeast of the study area, respectively. The Curlew Valley basalts are chemically similar to olivine tholeiites from the Snake River Plain and Blackfoot Reservoir areas in Idaho, but they do not show much similarity to basalts near Snowville, Utah, northeast of the study area. The Curlew Valley basalts are generally more iron rich and less alkalic than other basaltic rocks from the eastern Basin and Range Province.
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Helium isotope variations in peridotite, gabbro and basalt from the Kane Oceanic Core ComplexKonrad, Kevin 05 October 2012 (has links)
The Kane Oceanic Core Complex (OCC) is a valuable window into crustal architecture and chemical composition of the lithosphere beneath a slow-spreading ocean ridge. A suite of > 30 samples (comprised of whole rocks, mineral separates and basalt glasses) has been analyzed for ��He/���He isotope ratios and He concentrations. Gas extraction experiments included crushing in vacuum, step heating and fusion in a high-vacuum furnace. We found ��He/���He in the two freshest peridotites (harzburgite and olivine websterite) to be identical to ratios measured in basalt glasses collected from the Kane fracture zone-ridge axis intersection (8.4���8.7 R[subscript A]). Notably, the freshest and least deformed peridotite (a porphyroclastic harzburgite) has the highest helium content of any of the OCC ultramafic rocks (170 ncc STP/g), while the majority of its helium (70%) is released only upon melting. Lower helium contents (1-45 ncc STP/g) and more variable
��He/���He (2.0-6.3 R[subscript A]) are found in other more altered/deformed peridotite samples (whole rocks, clinopyroxene and orthopyroxene separates). For example, three mylonitized peridotites have lower helium contents compared to the less deformed peridotites. Troctolite intrusions from the Adam and Eve Domes appear to record very late-stage melt impregnation fed through dunite conduits near the MOHO. ��He/���He in these troctolites overlaps with values in the fresh peridotites and axial basalts, but extends to slightly higher values (8.6-9.0 RA). Collectively, fresh Kane peridotites and troctolites having He concentrations above 10 ncc STP/g show ��He/���He ratios of 8.4-9.0 RA that are higher than the median value (8.0-8.2 R[subscript A]) for mid-ocean ridge basalts. This suggests that domains of depleted upper mantle in the Kane region tend to have ��He/���He ratios of 9 RA or higher, similar to what is observed in the most trace-element depleted MORBs globally. Kane gabbroic rocks are more variable in 3He/���He. A subset of gabbros show systematically lower ��He/4He ratios (0.9-7.2 R[subscript A]), with He concentrations of 1-24 ncc STP/g, reflecting the increased importance of atmospheric and radiogenic components in several cases. Nonetheless, two whole rock gabbroic samples plus an amphibole separate have ��He/���He ratios of 7.6-8.0 R[subscript A] and He contents between 13 and 57 ncc STP/g. Variation in the sampling of a lithologically heterogeneous mantle source by the partial melting process may account for the observed ��He/���He variability of 7.6-9.0 R[subscript A] in peridotite, gabbro and basalt in the Kane area. / Graduation date: 2013
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Deep structure and sub-basalt exploration of the mid-Norwegian margin with emphasis on the Møre marginReynisson, Reynir Fjalar January 2010 (has links)
This thesis addresses the use of potential field data in two main topics: sub-basalt exploration and structure of the deeper crust. Synthetic models and forward models of the Møre margin were constructed to test the sensitivity of the various potential field methods. The synthetic models demonstrate that forward modelling of the gravity and magnetic data is a valuable tool in basement recognition in sub-basaltic settings and the use of gravity gradients further limits the modelling ambiguity and improves the basement mapping. Deep sills, as observed in the Møre Basin, cannot be identified from the gravity and magnetic data alone but the lava flows have a clear effect on the gravity and magnetic signature if thicker than ~1 km. Experiments with Euler Deconvolution reveal the limitations of the method in sub-basaltic settings. A 3D regional gravity and magnetic model of the Møre margin integrated with seismic and well data gives a novel view on the architecture of the continental crust, the distribution of high density lower crust, and the Moho topography. The isostatic response of the water and sediment loading reflected by the Moho provides further insight in the evolution of the margin. The results from the Møre margin model merged with results from a 3D model of the Vøring and Lofoten margins give a regional view on the deep structures on the mid-Norwegian margin. Combination of the modelling results and isostatic considerations provide means to address the origin of the lower crustal body on the margin and the evolution of the whole mid-Norwegian margin.
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Chemical Alteration Of Oil Well Cement With Basalt Additive During Carbon Storage ApplicationMokhtari Jadid, Kahila 01 December 2011 (has links) (PDF)
Capturing and storing carbon dioxide (CO2) underground for thousands of years is one way to reduce atmospheric greenhouse gases, often associated with global warming. Leakage of CO2 through wells is one of the major concerns when storing CO2 in depleted oil and gas reservoirs. CO2-injection candidates could be new wells, or old wells that are active, closed or abandoned.
To prevent the leakage, the possible leakage paths and the mechanisms triggering these paths must be examined and identified. It is known that the leakage paths can occur due to CO2-rock interaction and CO2-water-cement interaction.
Interaction between well cement and carbon dioxide has attracted much renewed interest because of its implication in geological storage of carbon dioxide. The diffusion of CO2-water through well cement is a long-term phenomenon which can take many thousand years. Partial pressure, porosity, permeability, cement type, moisture content and temperature are the factors that affect the carbonation of well cement. The objective of this research is to investigate the chemical reactions of the dissolved CO2 in the synthetic formation water with the plugs of well cement. Cement specimens were left in contact with CO2 saturated brine at 1100 psi and 65
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Untersuchung von Verbundwerkstoffen mit Basalt- und PBO-Faser-VerstärkungLiu, Jianwen 19 March 2008 (has links) (PDF)
Zur Erweiterung der Grundlagenkenntnisse für diese beiden bisher wenig genutzten Verstärkungsfasern werden in dieser Arbeit Einzelfaserzugversuche durchgeführt, um den Einfluss der Prüfbedingungen und der Faseroberflächenbehandlungen auf die mechanischen Eigenschaften der Fasern zu charakterisieren. Durch die Analysen der unimodalen und bimodalen Weibullverteilung wird der Zusammenhang zwischen der Faserzugfestigkeit und den kritischen Oberflächendefekten untersucht. Um den Einfluss der Faseroberflächenbehandlungen auf die Oberflächenenergien und Grenzflächenhaftung zu ermitteln, werden in dieser Arbeit der Schlichteauftrag aus wässriger Phase (Silan, Filmbildner), Plasmabehandlungen in verschiedenen Medien, Excimer-UV-Bestrahlungen in Anwesenheit verschiedener Monomeren und eine Säurebehandlung durchgeführt. Zur Charakterisierung der Oberflächentopografie der oberflächenbehandelten Fasern vor und nach dem Einzelfaserauszugversuch wird die Rasterkraftmikroskopie (AFM) verwendet. Der Effekt einer Plasmabehandlung auf die freie Oberflächenenergie der PBO-Fasern und die Grenzflächenscherfestigkeit wird mittels der Kontaktwinkelmessung und der Einzelfaserauszugprüfung untersucht. Um die durch diese Oberflächenmodifizierungen hervorgerufenen Veränderungen der mechanischen Verbundeigenschaften sowie der Faser-Matrix-Haftung zu charakterisieren, werden in dieser Arbeit sowohl endlosfaserverstärkte thermoplastische und duroplastische Unidirektionalverbunde bzw. kurzfaserverstärkte thermoplastische Verbunde als Modellfälle betrachtet, bei denen sowohl die Verstärkungsfasern als auch die Matrix signifikant unterschiedlich sind. Zur Verstärkung werden zwei ausgewählte Fasermaterialien (Basalt- und PBO-Fasern) und als Matrix zwei Thermoplaste (PP und PA6) sowie ein Epoxidharz ausgewählt. Der Einsatz von Commingling-Hybridfäden zur Entwicklung der thermoplastischen Unidirektionalverbunde erfordert Voruntersuchungen zur Lufttexturierung mit verschiedenen Düsen und Auswahl der günstigsten Prozessparameter.
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Diyarbakır yöresinde bazalt taşının yapı malzemesi olarak kullanımının incelenmesi üzerine bir araştırma /Kahveci, Aylin Erçin. Kadayıfçı, Abdullah. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Yapı Eğitimi Anabilim Dalı, 2008. / Kaynakça var.
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Hydrothermally altered basalts from the Mariana TroughTrembly, Jeffrey Allen January 1982 (has links)
No description available.
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The sulfur content and sulfur isotopic composition of Archean basaltic rocks at Matagami, Québec and their relationship to massive sulfides /Pasitschniak, Anna. January 1982 (has links)
No description available.
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The Southeast Indian Ridge water contents of MORB glasses and chemical effects of propagating riftsSylvander, Brendan A. 09 February 1998 (has links)
Graduation date: 1998
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A new perspective on melt inclusions : development of novel in-situ analytical protocols /Paul, Bence Timothy. January 2006 (has links)
Thesis (Ph.D.)--University of Melbourne, School of Earth Sciences, 2006. / Typescript. Includes bibliographical references (leaves 179-193).
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