This thesis presents the investigations of femtosecond laser machining on three different dielectric materials, namely quartz, sapphire and diamond. The laser micromachining experiments were performed with a Titanium:Sapphire solid state laser with a repetition rate of 1 kHz, centered at a wavelength of 800 nm and pulse duration of 150-200 femtoseconds (fs). A 5x microscope objective for surface micromachining and a 50x microscope objective for subsurface micromachining. The 50x microscope objective was used to obtain a smaller spot size and a shorter confocal parameter. The purpose of this research was to study the interaction between the femtosecond laser pulses and quartz, sapphire and diamond which have bandgap energies of 8.4 eV (λ=148 nm), 9.9 eV (125 nm), and c)· diamond 5.5 eV (225 nm) respectively. Since the photon energy of the laser was below the wide bandgap energies of the aforementioned dielectrics, the materials were essentially transparent to the incident laser. In order to study the behavior of the dielectric materials under femtosecond laser irradiation, several experiments with varying type and number of pulses (N) were performed, such as single pulse ablation, plural pulse ablation (N ≤ 100 pulses), multiple pulse ablation (N ≤ 100 pulses), and continuous lines micromachining on the surface and in the sub-surface of materials were performed. The features, damage, and structural changes introduced by femtosecond laser irradiation on the materials studied were characterized through examination of both the plan and cross-section views. The characterization process was carried out using optical microscopy (operated in the Nomarski mode), scanning electron microscopy, focused ion beam, atomic force microscopy, and transmission electron microscopy. The laser micromachining demonstrated distinct behaviors of the three wide bandgap materials. Quartz was very prone to cracking and showed nearwavelength alternating crystalline and amorphous sub-structure with the orientation parallel with respect to the electric field direction. Sapphire showed sub-wavelength ripples formation in lower fluences. Finally, diamond showed a strong tendency for ripples formation from near- to sub-wavelength spacing with the orientation of the ripples perpendicular and parallel with respect to electric field polarization. / Thesis / Master of Applied Science (MASc)

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1980. / Microfiche copy available in Archives and Science. / Bibliography: leaves 46-50. / by Raymond Joseph Harpin. / M.S.

Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN. / Includes bibliographies. / Ph.D.

The NE-SW trending Great Glen Fault (GGF) is one of mainland Scotland's most significant crustal-scale faults, although our understanding of its early kinematics is in question. Previous studies generally agree that the GGF was initiated as a Silurian sinistral strike-slip fault displacing c. 425 Ma isotopically dated granitic plutons. Stewart et al. (2001) argued that dikes fed by these plutons were sinistrally sheared by the GGF while in the sub-magmatic state, suggesting continuous strike-slip motion on the GGF by 425 Ma. Strike-slip offset post-dating overlying Devonian sedimentary basins is likely only a few tens of kilometers, requiring substantial (100s of kms) Silurian-aged strike-slip movement on the GGF in most plate reconstruction models for the Caledonian mountain belt, now exposed in East Greenland, Scandinavia, and Scotland. In contrast, a recent study (Searle 2021) has argued that motion on the GGF may instead have initiated in the Upper Paleozoic and that off-set is therefore minimal, bringing current restoration models into question. Several papers report widespread field and microstructural evidence from crystalline bedrock and overlying Devonian sedimentary rocks for brittle upper-crustal shearing on the GGF. However, evidence for high-temperature crystal plastic shearing at deeper crustal levels on the GGF, potentially of Silurian to Early Devonian age, is limited. During summer 2022, suites of oriented and plastically deformed metasedimentary rock samples were collected from the NW side (Moine/Lewisian gneisses and quartzites), center (Moine quartzites), and SE side (Dalradian quartzites) of the GGF. Additional samples included plutonic rocks from locations adjacent to the GGF and the associated Strathconnon fault that were believed to have been intruded during strike-slip motion, but after regional metamorphism and deformation in the surrounding Moine rocks. Microstructures and quartz c-axis fabrics from samples on the NW side and in the center of the GGF indicate a NW side up to the SW sense of displacement about NE to E plunging slip vectors, and these results are compatible with oblique sinistral motion on the GGF below the brittle-ductile transition zone during Silurian - Early Devonian times. However, radiometric dating is needed to prove the absolute timing of this shearing. In contrast, on the SE side of the GGF, NW side up or NW side down senses of shearing are indicated at different locations. Brittle fracturing is observed in all collected samples, overprinting the earlier high-temperature (300 - 650 °C) crystal fabrics and microstructures developed below the brittle-ductile transition zone. No convincing microstructural evidence for sub-magmatic shearing during pluton emplacement was found in the samples collected. However, the local presence of high-low temperature (c. 650 - 300 °C) solid-state deformation microstructures in both quartz and feldspar grains in these 430 - 425 Ma plutons suggests that the plutons were deforming internally in response to far-field stresses generated by shearing on the adjacent GGF and Strathconnon fault during cooling to background regional temperatures. / Master of Science / The Great Glen Fault (GGF) is one of mainland Scotland's most significant large-scale faults, although our understanding of its early motion is debated. Most geologists agree that the GGF began displacing existing rocks during the Silurian (c. 444 - 419 Ma), including igneous bodies, known as plutons, of approximately the same age (c. 425 Ma). Stewart et al. (2001) argued that during shearing, dikes fed by these plutons were deformed before cooling to background temperatures, which may suggest that the GGF was continuously undergoing lateral strike-slip motion by 425 Ma and that post-Silurian offset was likely only a few tens of kilometers. Most plate reconstruction models for the Caledonian mountain belt, now exposed in East Greenland, Scandinavia, and Scotland, assume that significant lateral motion and shearing occurred on the GGF during the Silurian. However, new research has suggested that the GGF was initiated several million years later, bringing current restoration models into question. Several published papers have reported widespread evidence for upper-crustal brittle shearing of crystalline bedrock and overlying Early Devonian (c. 420 - 359 Ma) sedimentary basins within the GGF. However, evidence for lower-crustal shearing during the same time frame, resulting in plastic deformation, is limited. To address this knowledge gap, I collected suites of oriented bedrock samples and 430 - 425 Ma plutonic rocks from locations adjacent to the GGF and associated Strathconnon Fault believed to have been intruded during strike-slip motion. Samples from the NW side and center of the GGF suggest oblique left-lateral motion within the fault zone, with the rocks on the NW side of the GGF moving upward relative to the SE side, compatible with current generally accepted models for the Silurian-Early Devonian age on the GGF; however, these results must be verified with radiometric dating to constrain the absolute timing of shearing. On the SE side of the GGF, vertical offset is variable at different locations. Brittle upper-crustal shearing is observed in all samples, which overprints early high-temperature (300 - 650 °C) deformation. Early lower-crustal shearing on the GGF is recorded by these deformation indicators and was followed by uplift and fracturing within the GGF of these initially lower-crust rocks. The local presence of solid-state deformation microstructures in the plutons suggest internal deformation due to shearing on the adjacent Great Glen and Strathconnon Faults during their cooling to regional background temperatures.

L'Orogène de l'Ungava correspond à la branche nord-est de l'Orogène Trans-Hudsonien et est situé sur la péninsule de l'Ungava dans le nord du Québec. La présence d'une éclogite de 1,8 Ga au sein du Domaine de Kovik dans l'Orogène de l'Ungava a été utilisée pour proposer une tectonique des plaques moderne active au Paléoprotérozoïque. Cette étude vise à contraindre la cinématique, la température et la chronologie de la déformation associée à une structure interprétée comme ayant permis l'exhumation de cette éclogite, la zone de cisaillement séparant le Domaine de Kovik du Domaine Nord. Nous avons combiné les observations de terrain le long de transects à travers le contact entre le Domaine de Kovik et le Domaine Nord, l'analyse microstructurale du quartz et de la titanite et des datations U-Pb sur titanite. Deux zones de cisaillement, localisées dans les orthogneiss du domaine de Kovik, ont été identifiées. La zone de cisaillement principale, distale au contact, est caractérisée par une cinématique de sommet-vers-le-sud et des fabriques d'axes-c du quartz associées à une déformation en aplatissement. La zone de cisaillement secondaire, proximale au contact, est caractérisée par une cinématique de sommet-vers-le-nord et des fabriques d'axes-c du quartz associées à une déformation plane. La température de déformation est contrainte à 627 et 580 ± 50°C pour les zones de cisaillement principale et secondaire, respectivement. La géochronologie U-Pb sur titanite a permis de définir deux populations de titanite. La vielle population, contrainte à ~1890 Ma, est contemporaine de la mise en place de la grande province ignée du Circum-Supérieur. La jeune population, contrainte à ~1740 Ma, est interprétée comme représentant la réinitialisation de la vieille population pendant un épisode de déformation tardive possiblement relié à l'effondrement de l'orogène. Nous interprétons que le contact entre le Domaine de Kovik et le Domaine Nord représente un détachement.

Thesis (MSc (Earth Sciences))--Stellenbosch University, 2008. / Detailed geological mapping and a structural analysis of auriferous quartz veins were undertaken in the Karibib region of the Pan-African Damara belt in central Namibia. The study focuses on the formation and controls of quartz-vein sets and associated lodegold mineralization in heterogeneous, siliciclastic- and marble- dominated amphibolitefacies host rocks around the Navachab gold mine and adjacent areas. Two main arrays of shallowly-dipping quartz veins can be distinguished that form a conjugate set. Steep, bedding-parallel and high-angle cross-cutting veins also occur, but play a subordinate role for mineralization. The orientation of the main conjugate set and progressive deformation of these quartz veins indicate that veining occurred during the late stages of the main phase of NW-SE directed, subhorizontal shortening (D2) and associated NW-verging folding and top-to-the-NW thrusting. Cross-cutting relationships with plutonic rocks indicate a timing of ca. 540 Ma for the mineralization. The quartz veins sets show a consistent orientation irrespective of their location with respect to NE-trending, NW-verging first-order fold structures that were previously considered to be pertinent for the mineralization. The quartz vein sets also cross-cut different lithologies at high angles. This suggests that the regional strain (D2) was the first-order control of quartz vein formation. More localized lithological and/or structural controls played, however, an important factor for the formation of economicgrade mineralization. Thick and closely spaced quartz veins in steeply dipping rocks of the Navachab open pit form a more than 150m thick economic-grade vein swarm. In this structural situation and during layer-normal subhorizontal shortening, the host rocks experienced high extensional strains in a vertical direction, favouring the formation of subhorizontal extension fractures.

A new barometric technique measuring stored stress in quartz inclusions via laser Raman microspectrometry was employed in an attempt to elucidate the extent of highpressure (HP) metamorphism in the Llano Uplift of central Texas. Rare lithologies within the Llano Uplift contain mineralogical evidence of HP metamorphism (pressures from 1.4 to 2.4 GPa at temperatures from 650 to 775°C), but much of the uplift is composed of felsic gneisses lacking any HP signature; these felsic gneisses may never have transformed to HP assemblages, or they may have been thoroughly overprinted by later low-pressure events. Barometry via laser Raman microspectrometry computes entrapment pressure for a quartz inclusion in garnet from measurement of the displacements of its Raman peak positions from those of a quartz standard at atmospheric pressure. Quartz inclusions in garnets that grew in felsic gneisses under HP conditions should retain HP signatures, despite later overprinting. Application of the Raman microspectrometry technique should therefore allow barometry of previously uncharacterizable rocks. For two localities in the Llano Uplift, entrapment pressures from Raman barometry (0.6-0.7 GPa and 0.2-0.3 GPa) were substantially lower than pressures expected based on conventional barometers (1.4 GPa and 1.6-2.4 GPa). This absence of any HP signatures in the Llano rocks contrasts with more successful applications of the Raman technique by previous workers in high P/T blueschist-facies rocks. A key difference in the Llano rocks is that they reached peak temperatures at which intracrystalline diffusion in garnet, driven by compositional gradients produced during growth, had noticeable effects: complete homogenization of growth zoning had occurred in the locality that produced the greatest discrepancies between Raman and conventional pressures, and modest relaxation of zoning occurred in the locality with the smaller discrepancies. The failure of the Raman technique to recover pressures consistent with conventional barometry in the Llano Uplift is therefore attributed to relaxation of stress on the quartz inclusions as the result of intracrystalline diffusion within the garnet. This conclusion suggests that use of the Raman barometric technique must be restricted to rocks whose time-temperature histories produce only very limited intracrystalline diffusion in garnet, typically those rocks whose peak metamorphic temperatures fall at or below upper amphibolite-facies conditions. / text

The Mokrsko-West deposit, situated about 20 km south from Prague, is one of the most important gold deposits in the Bohemian Massif. We can find hydrothermal quartz veins in two types of host rocks: tonalite in the Central Bohemian Plutonic Complex (CBPC) and amphibolite in the Jílové Belt (JB). A several generations of the quartz veins with different mineralization were found in the deposit. This study has several objectives. At first, it determines and compares the chemistry of quartz samples from different generations of hydrothermal veins. In addition, this work describes the distribution of the most important trace elements. Lastly, the work compares the potential differences in the chemistry of samples from the different host rocks (CBPC and JB). With the use of the LA-ICP-MS, 16 quartz samples from the Mokrsko-West deposit were analysed. Finally, 101 analyses were realized. From the analysed trace elements, the most important were Li, Mg, Al, Ca, Fe, Cu, Zn, As, Sb and Pb. Aluminium affects the concentration of the most of analysed trace elements. Positive correlation between Al and the other metals was also found. The samples with high Al content also showed high concentrations of other metals (Fe, Cu, Zn, Pb) and As. Samples with lower Al content showed lower concentration of other metal...

Le but de l'étude est de comprendre et de prédire les performances de détection en phase gazeuse des capteurs chimiques à surface de matériaux sensibles. Les travaux ont porté sur des microbalances à quartz revêtues de polysiloxanes fonctionnalisés. Des mesures à l'équilibre, en exposant ces capteurs à différentes vapeurs organiques, ont mis en évidence la sélectivité des matériaux employés. Pour rationaliser ces résultats, les étapes impliquées dans la détection ont été examinées. Des mesures par PM-IRRAS ont permis de montrer la proportionnalité de la réponse vis-à-vis de la quantité d'analyte absorbé. Des affinités en phase condensée ont été déterminées par une nouvelle méthode par RMN d’études de mélanges sans solvant. L'application de cette méthode à des composés modèles a validé le calcul de l'enthalpie de mélange par l'approche de Hansen. Celle-ci permet également d’obtenir calculer les coefficients de Hansen des matériaux sensibles avec des méthodes de contributions de groupes. Enfin, sur ces résultats, un modèle numérique a été construit pour calculer a priori la réponse d'un capteur à partir de la formule chimique des composés sensible et de l'espèce détectée. / The aim of this study is to understand and model the responses of coated chemical sensors for gas phase detection. The work exposed here focuses on quartz crystal microbalance (QCM) coated with functionalized polysiloxanes. Measurements were carried with the QCM exposed to organic vapours when equilibrium was reached. It has been shown that selectivity depends on the material used. To understand that selectivity, each step involved in the detection has been investigated. First of all, with PM-IRRAS, we verified that the frequency shift was proportional to the amount of absorbed analyte. Then, affinity in liquid phase has been determined through a new methodology by NMR. It has also been used, on model system to prove the applicability of Hansen solubility coefficient to calculate mixing free enthalpy. For polymers, those coefficients have been determined using NMR combined with group contribution methods. Based on these descriptors, a numerical model has been built to calculate a priori the performance of a sensor based on, the chemical structure of the sensitive material and of the detected compound.

Les propriétés pétrophysiques des réservoirs silicoclastiques sont influencées par de nombreux facteurs sédimentaires et diagénétiques. Les principaux phénomènes diagénétiques affectant les réservoirs sont généralement la cimentation de quartz et les compactions mécanique et chimique. Des réservoirs gréseux ayant des contextes géologiques différents ont été considérés dans cette étude ; les réservoirs carbonifères d’origine deltaïque-marine du bassin des Palmyrides-Sud en Syrie et les réservoirs cambro-ordoviciens du bassin de Sbaa en Algérie. Cette thèse consiste à établir l’histoire diagénétique, déterminer les contrôles sédimentaires et structuraux influençant l’évolution des phénomènes diagénétiques, caractériser l’habitus des cristaux authigènes de quartz formés autour les grains détritiques et aussi mettre en relation les différentes contrôles sédimentaires et diagénétiques sur les caractéristiques des pores et ainsi que sur la variation de la perméabilité. L’histoire diagénétique entre le réservoir du bassin de Sbaa se caractérise par une forte cimentation de quartz composée de trois phases Q1, Q2 /et Q3, par tapissage illitique et ainsi par une importante compaction chimique liée à certains faciès glaciaires et également une cimentation d’argiles principalement en illite mais surtout dans les champs d’Oued Zine et de Bou Hadid. A l’exception du champ de Hassi Ilatou, où une faible cimentation de quartz composée de Q1 a eu lieu. Alors que la diagenèse des réservoirs gréseux du bassin des Palmyrides-Sud est représentée par une faible cimentation de quartz composée d’une seule phase Q1, une absence de compaction chimique, ainsi qu’une cimentation d’argiles dominée par la chlorite et les kaolins. Les analyses microthermométriques des inclusions fluides dans les surcroissances de quartz mettent en évidence une silicification se déroulant principalement entre 100 et 160°C dans les deux bassins. D’après la reconstitution de l’histoire thermique de bassin, cet intervalle de température a été atteint entre le Viséen et la fin du Namurien dans le bassin de Sbaa et au Crétacé supérieur-Paléocène dans le bassin des Palmyrides-Sud. Les analyses isotopiques indiquent une eau originelle météorique et marine, progressivement réchauffée lors de l’enfouissement, et s’enrichissant au fur et à mesure en ¹⁸O dans les pores intergranulaires et des fluides évolués et chauds à l’origine des filonnets. L’habitus des cristaux authigènes de quartz et la forme de croissance montrent une relation avec les phases de ciment de quartz, son taux et la présence/absence de gaz. En effet, des cristaux à prisme court, tronqués par des facettes additionnelles, et des cristaux trapus caractérisent les grès cimentés par une seule phase de quartz authigène, et une fréquence importante des cristaux de quartz à multiples nucléas est constatée dans ces grès. Des cristaux à prisme développé et rarement des cristaux à prisme court caractérisent les grès contenant deux phases du ciment de quartz. Des cristaux peu développés et limités à quelques faces sont présents dans les grès cimentés par trois phases du ciment de quartz dans la paléozone à eau du réservoir dans le champ ODZ. Une forme de croissance en escalier est présente uniquement dans ces derniers grès. La présence des inclusions à hydrocarbures dans les surcroissances de quartz dans la partie supérieure du réservoir ordovicien du champ de Oued Zine indique que la mise en place des hydrocarbures dans le réservoir a été contemporaine à la cimentation de quartz à des températures 100-140°C en raison de la paléostructure anticlinale dans ce champ. Un deuxième épisode a eu lieu suite à la fracturation hercynienne à des températures comprises entre 117-185°C qui augmente vers le nord-ouest du bassin. La composition du gaz dans les inclusions monophasées (92 ± 5 mole %) est comparable à la composition actuelle du gaz dans le réservoir. / Petrophysic properties of siliciclastic reservoirs are influenced by many sedimentary and diagenetic factors. The main diagenetic processes affecting the reservoir quality are quartz cementation and mechanical and chemical compaction. The cementing of quartz plays a role in reducing the porosity as it precipitates occupying intergranular porosity. However, its influence on the evolution of permeability is not well known because the morphology of authigenic quartz crystals and controls responsible for this morphology remain poorly understood. Sandstone reservoirs with different geological settings were considered in this study; Carboniferous reservoirs of deltaic-marine Palmyrides South Basin (fields: Arak, Debayate South, and Sukhneh) in Syria and the Cambro-Ordovician reservoirs Sbaa Basin (fields : Hassi Ilatou , Hassi Ilatou NE, Bou Hadid, Oued Zine, and Bou Hadid W) in Algeria. They have widely varying porosities both laterally and vertically and permeabilities. Thus, this thesis is to establish the diagenetic history, determine the sedimentary and structural controls influencing the evolution of diagenesis, characterize crystallographic habits of authigenic quartz formed around the detrital grains and to relate the different sedimentary controls and diagenetic on pore characteristics and as well as the variation of the permeability. In the Sbaa Basin, the presence of inclusions hydrocarbons allowed to reconstruct the history of gas migration. The diagenetic history of the Sbaa Basin is characterized by strong cementing quartz composed of three phases Q1, Q2 / Q3, illite coatings, significant chemical compaction, and also by illite cements, especially in the fields of Oued Zine and Bou Hadid. However, Hassi Ilatou field shows low quartz cementation (Q1). In addition, reservoir sandstones of the Palmyrides-South Basin show low quartz cementation composed of a single phase Q1, an absence of chemical compaction, as well as clay cementation dominated by chlorite and kaolin characterize the diagenesis history. Microthermometric analyzes of fluid inclusions located in quartz overgrowths show that the silicification occurred mainly between 100 and 160 °C in both basins. According to the reconstruction of the thermal history, these temperatures have been reached between the end of the Visean and Namurian for the Sbaa Basin and Upper Cretaceous-Paéocène for the Palmyrides-South Basin. Isotope analyzes indicate marine/meteoric water gradually heated during burial, and enriched in ¹⁸O in intergranular pores and evolved hot fluids are responsible for vein precipitation. The habits of quartz overgrowth crystals and growth forms observed in the studied sandstones show a relation with the number of quartz cement phases. Effectively, crystals with short prisms, truncated by supplementary faces, and large crystals characterize one-phased (Q1) cemented sandstones. In addition, quartz crystals of multiple nucleations are frequent in these sandstones. However, crystals with long prisms and rarely crystals with short prisms characterize two-phased (Q1 and Q2) cemented sandstones. Crystals of poorly developed faces are present in three-phased (Q1, Q2, and Q3) cemented sandstones. Step-like striation present only in these sandstones. Methane inclusions in the quartz overgrowths of the upper part of Ordovician reservoir of Oued Zine indicate that the gas emplacement into the reservoir occurred synchronically with early quartz cementation in the sandstones located near the contact with the Silurian gas-source rocks at 100-140°C during the Late Carboniferous period and the late Hercynian episode fracturing at temperatures between 117 and 185°C. Microthermometric data on gas inclusions reveal the presence of an average of 92 ± 5 mole % of CH4, which is similar to the present-day gas composition in the reservoirs.