Rocks of the Morenci-Metcalf district consist of Precambrian metaquartzite-schist, granodiorite, and granite overlain by Paleozoic and Mesozoic sediments. Intrusion of igneous rocks, emplacement of breccia masses, and associated hydrothermal activity occurred in Laramide time. Breccias of the district are associated with the youngest sialic intrusive complex. This sequence includes intrusion of the Older Granite Porphyry stock, main stage district hydrothermal alteration, quartz veining, breccia formation, main stage district hydrothermal mineralization, and intrusion of the Younger Granite Porphyry plug. Breccia formation in the Morenci-Metcalf district is similar to breccia descriptions reported in the literature for other porphyry copper deposits. Three breccia types, of separate and distinct origins, are herein described as the Morenci, Metcalf and King, and Candelaria Breccias. The Morenci Breccia is an intrusion breccia that has formed along a pre-existing structural feature during the ascent and emplacement of the Older Granite Porphyry stock. It exhibits an oblate lenticular shape with angular to subrounded fragments in a matrix of quartz, K-feldspar, biotite, and minor rock flour. The Metcalf-King Breccias and numerous smaller breccia masses are the remnants of an original Older Granite Porphyry mantle above the ascending Younger Granite Porphyry complex. The breccia masses occur as large 'xenoliths' floating within the Younger Granite Porphyry plug and were formed by surging and collapse during emplacement of this intrusive. Fragments in the Metcalf and King Breccias grade from angular in the central core to rounded at the contacts and occur in a matrix of sericite, K- feldspar, quartz, and rock flour. The Candelaria Breccia is an explosion pipe and is the largest continuous breccia mass in the district. It is oval with an inverted cone appearance consisting of angular to subangular equidimensional fragments in a matrix of sericite, quartz, specularite, and rock flour. All the breccia masses occur within and subsequent to the district phyllic (quartz-sericite-pyrite) alteration zone. Main stage district copper mineralization postdates emplacement of the Older Granite Porphyry stock and breccia formation, and is prior to the intrusion of the Younger Granite Porphyry plug. Late stage quartz-sericite-pyrite-chalcopyrite veinlets occur in the Metcalf-King Breccia group. Field mapping and laboratory studies indicate that the Older Granite Porphyry stock appears to have been the main district mineralizer.

The PhD. thesis deals with the morphostructural evolution of the valley network of the Biala Lądecka river, (further refer as BL) during the Late Cenozoic. In this work, the selected methods as geomorphological research (morphostructural analysis, geomorphological mapping), structural-geological research (paleostres analysis) and geophysical survey on selected sites were used, to answer the questions of river basin development and its relationship with predicted tectonic activity within the area, as well as with anticipated or already known paleohydrographic changes. The BL basin is situated within the Rychlebské hory Mts. / Góry Złote (northern and eastern parts of the basin), Králický Sněžník (southern part) and the Krowiarki Mts. (western part) in Poland. The Marginal Sudetic fault zone, which represents one of the most important tectonic zones in the Central Europe, passes in vicinity of the study area as well as the regionally important Bělský fault, which passes directly through the BL basin. The results of the analysis indicate that the BL basin has undergone very complex development due to tectonic movements since Miocene up-to-day. Based on the results of the paleostress analysis, which was performed on the dated volcanites in Lutynia - Lądek Zdrój area, the parameters of the palaostress...

A quartz diorite intrusion of probable early Tertiary age that crops out over at least 6 square miles in the Palo Verde Ranch area in Pinal County, Arizona was mapped as a distinct intrusion. The quartz diorite intrudes an area comprising Pinal Schist, Oracle granite, andesitic flows, granoaplite, and dike rocks including both pegmatite and diabase. Two major physical features, the Owl Head Buttes and Chief Buttes volcanic areas, both remnants of an extensive early Tertiary series of flows of intermediate composition that covered the area, now remain as lava-capped buttes above the pediment. Weak but persistent fracture-controlled copper mineralization is found in the quartz diorite and the Pinal Schist at or near their mutual contacts in the form of chrysocolla, malachite, black copper oxides, chalcocite, chalcopyrite, and bornite, in decreasing order. Pyrite is rare. Alteration related to northeast and northwest-trending fractures increases in intensity from the common propylitic to argillic to the northeast toward the San Juan claims area. A barely discernible increase in copper sulfides mirrors the alteration zoning, although geochemical sampling showed background copper in the quartz diorite to be more uniform away from fractures.

Use of Re-Os systematics in sulfides from the Bagdad porphyry Cu-Mo deposit provide information on the timing of mineralization and the source of the ore -forming elements. Analyzed samples of pyrite, chalcopyrite and molybdenite mainly from the quartz monzonite and porphyritic quartz monzonite units are characterized by a moderate to strong potassic alteration (secondary biotite and K- feldspar). Rhenium concentrations in molybdenite are between 330 and 730 ppm. Two molybdenite samples from the quartz monzonite and porphyritic quartz monzonite provide a Re-Os isotope age of 71.7 ± 0.3 Ma. A third sample from a molybdenite vein in Precambrian rocks yields an age of 75.8 ± 0.4 Ma. These molybdenite ages support previous suggestions of two mineralization episodes in the Bagdad deposit. An early event at 76 Ma and a later episode at 72 Ma. Pyrite Os and Re concentrations range between 0.008-0.016 and 3.9-6.8 ppb, respectively. Chalcopyrite contains a wide range of Os (6 to 91 ppt) and Re (1.7 to 69 ppb) concentrations and variable ¹⁸⁷Os/¹⁸⁸Os ratios that range between 0.13 to 22.27. This variability in the chalcopyrite data may be attributed to different copper sources, one of them the Proterozoic volcanic massive sulfides in the district, or to alteration and remobilization of Re and Os. Analyses from two pyrite samples yield an eight point isochron with an age of 77 ± 15 Ma and an initial ¹⁸⁷Os/¹⁸⁸Os ratio of 2.12. This pyrite Re-Os isochron age is in good agreement with the molybdenite ages. We interpret the highly radiogenic initial 1870s/188Os as an indication that the source of Os and, by inference, the ore-forming elements for the Bagdad deposit, was mainly the crust. This conclusion agrees with previous Pb and Nd isotope studies and supports the notion that a significant part of the metals and magmas have a crustal source.

L'activité volcanique Cénozoïque de la plaque arabique offre l’exemple d’un volcanisme intra-plaque développé dans un contexte géodynamique complexe. Après la construction des trapps basaltiques du plateau yémeno-ethiopien, vers 31 Ma, à partir de l’Oligocène terminal, une importante activité volcanique se développe, liée à la déchirure du bouclier arabo-nubien (l’ouverture de la Mer Rouge) et la convergence des plaques Arabique et Eurasienne (zone de suture du Bitlis-Zagros). Au nord de la plate-forme arabique, le volcanisme syrien s’implante dans un contexte général de compression, autour de la ceinture de plissement des Palmyrides et des zones de déformation adjacentes (graben de l'Euphrate et système de faille de la Mer Morte). Cette thèse porte sur l'évolution volcano-tectonique de la partie nord de la plaque Arabique, en particulier celle de la Syrie, combinant des études géochronologiques, géochimiques et morpho-structurales et modélisation géophysique. Notre analyse morpho-structurale de la province volcaniques de Harrat Ash Shaam (HASV), au sud des Palmyrides, a permis de caractériser numériquement plus de 800 cônes volcaniques monogéniques répartis entre le Sud Syrien, la Jordanie et le Nord de l’Arabie Saoudite. Cette étude de la distribution des cônes volcaniques, jointe aux données existantes sur l’épaisseur de la couverture sédimentaire traversée démontre que la corrélation négative constante entre l’intensité des éruptions volcaniques et la profondeur au socle est, de fait, influencée par le contexte tectonique. L’analyse normative de la distribution des cônes volcaniques, comparée à l'épaisseur des sédiments, est essentielle pour caractériser la tectonique d'extension dans des différentes zones. La télédétection, les observations sur le terrain, et notre base de données de plus de 40 nouvelles datations potassium-argon, entre 50 ka et 18 Ma, nous permettent de préciser l’évolution volcano-tectonique de la Syrie. Cette approche pluri-disciplinaire, appliquée au plateau du Al-Lajat, le champ volcanique le plus récent de HASV, nous a permis, d’abord, de proposer un modèle chronologique pour le processus d'altération en relation aux changements paléoclimatiques du Quaternaire. Elle a surtout permis de reconstituer l'évolution volcano-tectoniques du Nord de la plaque arabique, au cours du Cénozoïque et de situer différents styles d’extension responsables de l’activité volcanique. Le volcanisme commence à la fin de l’Oligocène et au Miocène inférieur, entre ~ 26 Ma et ~ 16 Ma, au sud des Palmyrides, dans la province de HASV, dans un contexte tectonique extensif. Du Miocène au Quaternaire, entre ~ 19 Ma et ~ 0,08 Ma, des champs volcaniques se développe au nord des Palmyrides, conséquence d’extensions tectoniques de second ordre. A partir du milieu du Miocène, la compression augmente et le développement magmatique se poursuit potentiellement dans une ambiance tectonique de rotation antihoraire. Au sud des Palmyrides cela correspond à l’activité volcanique constante au cours des 13 derniers millions d’années. Au nord, cette phase d’activité liée à la tectonique de rotation est concentrée dans l’espace et le temps ; elle correspond au Plateau d’Homs, dans le NW Palmyre, entre 6,3 et 4,3 Ma.Nous proposons un nouveau modèle d'évolution volcano-tectoniques pour la province volcanique de HASV. Il souligne le rôle essentiel joué par l'hétérogénéité de la lithosphère (sous les chaînes du Liban – anti-Liban et la zone de plissement des Palmyrides) dans la formation du volcanisme à partir du milieu du Miocène. Nos modèles géophysiques permettent d’estimer à ~150 km la profondeur moyenne de la limite lithosphère-asthénosphère. A l’analyse des données géochimiques des laves, la zone à l’ouest de HASV où cette limite apparaît moins profonde, à ~ 110 km, s’expliquerait par une anomalie thermique plutôt que par une remontée asthénosphérique. Géochimiquement, les laves Cénozoïques syriennes sont alcalines et sub-alcalines et présentent les caractères de magma émis dans un contexte continental intra-plaque. Ce sont des basanites et des téphrites, des basaltes, des andésites et des trachy-andésites basaltiques et des trachybasaltes. 30 échantillons des différentes provinces volcaniques syriennes montrent une variation significative des signatures des éléments traces incompatibles. Le processus de genèse de ces magmas montre une influence négligeable de la contamination crustale, et un effet de la cristallisation fractionnée limité à l'olivine et au clinopyroxène. Nos résultats montrent que les laves syriennes ont été produites par des taux variables de fusion partielle à partir de niveaux différents dans le manteau lithosphériques présentant localement des hétérogénéités. Le rapport LREE / MREE nous permet de montrer non seulement comment le degré de fusion partielle varie spatialement et temporellement au cours des derniers 18 Ma, mais encore d’illustrer comment varie le degré et le style de la tectonique au cours de cette période. L’une des conséquences de ce contexte tectonique pourrait être la migration d’hydrocarbures vers l’ouest du fait de l’extension crustale au Plio-Quaternaire dans la zone du graben de l’Euphrate à l’Est ; cette migration pourrait être guidée vers une zone de la croûte préalablement fracturée située au NW de la Syrie.En conclusion, le volcanisme cénozoïque de la Syrie résulte d’une tectonique extensive, influencée périodiquement par la convergence arabo-eurasienne, au nord et à l’est, convergence qui provoque des styles tectoniques de rotation ; cette tectonique contrôle la fusion partielle à différents niveaux dans le manteau. Le volcanisme du Nord de la plaque arabique se développe dans le cadre de l’ouverture de la Mer Rouge et débute en même temps que l’activité au sud de la mer Rouge. Il se poursuit jusqu’à la période historique, progressivement amorti vers le nord, l’extension étant contrariée par le cadre compressif à la marge Arabie-Eurasie. / The Cainozoic volcanic activity in the Arabian plate offers an excellent opportunity to study the intra-plate volcanism related to a complex tectonic setting. After the emplacement of the Yemeni-Ethiopian continental flood basalt plateau, ~ 31 Ma, since the Late Oligocene, widespread volcanic activity has erupted, accompanying the separation of the Arabian-Nubian Shield (development of Red Sea rifting) and the convergence between the Arabian and Eurasian plates (building of the Bitlis-Zagros thrust belts). In the northern part of the Arabian platform, the Syrian volcanism has taken place in a general compressional context, surrounding the Palmyride fold belt and adjacent to other deformation zones (e.g. the Euphrates graben and Dead Sea fault system). This thesis focuses on the volcano-tectonic evolution of the northern part of the Arabia plate, particularly in Syria, and essentially combines geochronological, geochemical, and morpho-structural studies, in addition to supplementary geophysical models. Our morpho-structural analyses of the Harrat Ash Shaam volcanic province (HASV) to the south of Palmyride, digitally characterise more than 800 monogenic volcanic cones placed in Syria, Jordan, and Saudi Arabia. These new data, together with the availability of sediment thickness data, give rise to a new volcano-tectonic approach. This study shows that the consistent negative correlation between the intensity of volcanism and basement depth is influenced by the tectonic setting. The normative analysis of the distribution of volcanic cones in relation to sediment thicknesses is critical when comparing the extension of tectonics in different zones. Remote sensing imagery, field work and our > 40 new K-Ar ages dataset ranging from ~0.05 million years (Ma) to ~18 Ma allow us to precise the Syria volcano-tectonic evolution through time. Regarding the youngest lava flows of HASV, the integration of the results makes it possible to suggest a chronological model for the alteration processes in relation to Quaternary palaeoclimatic changes. We reconstruct the volcano-tectonic evolution in Syria during the Cainozoic, and suggest different extension styles to explain the volcanism. It started during the Late Oligocene and the Early Miocene, between ~26 Ma and ~16 Ma to the South of Palmyride at HASV in an extensional tectonic context. From the Miocene to the Quaternary, between ~19 Ma and ~0.08 Ma, the volcanism developed to the North under second order extension tectonic conditions. Since the Mid-Miocene, the compression has increased and the magma erupted in relation with a possible counter-clockwise rotation tectonic relative motion. South of Palmyride it corresponds to the widespread eruptive phase during the last 13 Ma. To the North, this phase, linked to rotational tectonics appears concentrated in superficies and time; it corresponds to the Homs plateau, NW Palmyride, between 6.3 and 4.3 Ma. We suggest a new volcano-tectonic evolution model for the HASV. It highlights the essential role of lithosphere heterogeneity beneath Lebanon, in particular the anti Lebanon Mountains and Palmyride thrust belts, in triggering the Mid-Miocene volcanism. Our geophysical models estimate mean lithosphere – asthenosphere boundaries at about 150 km depth. According to geochemical data, the zone of shallowest depth ~110 km, W of HASV, could be the result of a thermal anomaly, instead of an asthenospheric upwelling. Geochemically, the Cainozoic Syrian lavas are alkaline and subalkaline rocks, typical of magma emitted in continental intraplate contexts. They are basanites and tephrites, basalts, basaltic andesites, basaltic trachyandesites, and trachybasalts. Thirty samples from different Syrian volcanic provinces show significant variation in terms of incompatible trace element signatures. Crustal contamination plays a negligible role in the process of magma genesis, as does crystal fractionation, essentially restricted to olivine and clinopyroxene. Our results show that the Syrian lava has been generated by variable rates of partial melting from different levels of a locally heterogeneous lithospheric mantle. The LREE/MREE ratio not only illustrates how the degree of partial melting was changed spatially and temporally during the last ~18 Ma, but it also illustrates how the degree and style of extension tectonics changed through time.

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