Petrology and geochemistry of volcanic rocks from ODP Sites 134-827, 134-829 and 134-830

Igneous rocks recovered from Ocean Drilling Program (ODP) Leg 134 Sites 827, 829, and 830 at the toe of the forearc slope of New Hebrides Island Arc were investigated, using petrography, mineral chemistry, major and trace element, and Sr, Nd, and Pb isotopic analyses. Basaltic and andesitic clasts, together with detrital crystals of plagioclase, pyroxenes, and amphiboles embedded in sed-lithic conglomerate or volcanic siltstone and sandstone of Pleistocene age, were recovered from Sites 827 and 830. Petrological features of these lava clasts suggest a provenance from the Western Belt of New Hebrides Island Arc; igneous constituents were incorporated into breccias and sandstones, which were in turn reworked into a second generation breccia. Drilling at Site 829 recovered a variety of igneous rocks including basalts and probably comagmatic dolerites and gabbros, plus rare ultramafic rocks. Geochemical features, including Pb isotopic ratios, of the mafic rocks are intermediate between midocean ridge basalts and island arc tholeiites, and these rocks are interpreted to be backarc basin basalts. No correlates of these mafic rocks are known from Espiritu Santo and Malakula islands, nor do they occur in the Pleistocene volcanic breccias at Sites 827 and 830. However, basalts with very similar trace element and isotopic compositions have been recovered from the northern flank of North d'Entrecasteaux Ridge at Site 828. It is proposed that igneous rocks drilled at Site 829 represent material from the North d'Entrecasteaux Ridge accreted onto the over-riding Pacific Plate during collision. An original depleted mantle harzburgitic composition is inferred for a serpentinite clast recovered at 407 meters below seafloor (mbsf) in Hole 829A. Its provenance is a matter of speculation. It could have been brought up along a deep thrust fault affecting the Pacific Plate at the colliding margin, or analogous to the Site 829 basaltic lavas, it may represent material accreted from the North d'Entrecasteaux Ridge.

Stable isotope record and planktonic foraminiferal fragmentation of the late Pleistocene section of ODP Hole 134-828A

A high-resolution record of foraminiferal fragmentation (a dissolution indicator) for the last 250 k.y. (isotopic Stages 1 to 7) is identified in the upper 61.9 m of Ocean Drilling Program (ODP) Hole 828A, west Vanuatu. This record is comparable in detail to the atmospheric CO2 record and the d18O stack. Phase shifts between preservation spikes and maximum ice volumes (d18O of Globigerinoides sacculifer) are analogous to those on Ontong Java Plateau. Mass spectrometer (AMS14C) dating of a sample taken at the base of dissolution cycle B1 and the position of the last glacial maximum indicates a lag in time of ~8 k.y. in the Vanuatu region for the last glacial termination. When dissolution spikes are compared with minimum ice volumes there is no phase shift for the last two glacial terminations. The difference between Vanuatu and Ontong Java Plateau may be explained by local CO2 sinks and the interplay between intermediate and deep water masses. Terrigenous input increasingly affected sediment of Hole 828A on the North d'Entrecasteaux Ridge (NDR) as it approached Espiritu Santo Island. Mud and silt suspended in mid-water flows become important after 125 ka, while turbidites bypass the New Hebrides Trench only towards the last glacial maximum (LGM). Terrigenous supply seems to affect the lysocline profile that changed from an "open ocean" to a "near continent" type, thus favoring dissolution. Fragmentation of planktonic foraminifers is a more sensitive indicator of lysocline variations than is foraminiferal susceptibility to dissolution, the foraminiferal dissolution index, the abundance of benthic foraminifers, or CaCO3 content. A modern foraminiferal lysocline for the neighboring area (between 10°S and 30°S, and 160°E and 180°E) is found at 3.1 km below sea level, compared to west Vanuatu where it is shallower. The past lysocline level was deeper than 3086 m during intervals of dissolution minima, and ranged from ~2550 to 3000 m during intervals of dissolution maxima. The high sedimentation rates (in the order of 10 to 50 cm/k.y.) found in Hole 828A offer a great potential for future high-resolution studies either in this hole or other western localities along the NDR. Areas of high sedimentation near continental regions have been discarded for paleoceanographic and/or paleoclimatic studies. Nonetheless, conditions analogous to those found in Hole 828A are expected to occur in many trench areas around the world where mid-water flows have preserved as yet undiscovered fine high-resolution sedimentary records.

Calcareous nannofossil biostratigraphy of ODP Leg 134 sites

Seven sites drilled in the central New Hebrides Island Arc during Ocean Drilling Program Leg 134 yielded varying quantities of upper Eocene through Pleistocene calcareous nannofossils. Most of the Miocene and Pliocene strata were absent from Sites 827-831 drilled along the collisional boundary between the Australia and Pacific plates where the North d'Entrecasteaux Ridge and Bougainville Guyot are being subducted. Sites 832 and 833, drilled in the intra-arc North Aoba Basin, contained upper Miocene through Pleistocene and early Pliocene through Pleistocene nannofossils, respectively. Detailed range charts displaying species abundances and age interpretations are presented for all of the sites. Despite problems of reworked assemblages, poor preservation, overgrowths and/or dilution from volcaniclastics, the nannofossil biostratigraphy delineates several repeated sections at Site 829 in the accretionary prism adjacent to Espiritu Santo Island. Paleogene pelagic sediments equivalent to those in a reference section at Site 828 appear to have been scraped from the downgoing North d'Entrecasteaux Ridge and accreted onto the forearc during the Pleistocene. Other sediments in the forearc include Pleistocene olistostromal trench-fill deposits containing clasts of various ages and compositions. Some of the clasts and olistoliths have affinities to rocks exposed on the neighboring islands and environs, whereas others are of uncertain origin. The matrix of the olistostromes is predominately Pleistocene, however, matrices of mixed nannofossil ages are frequently encountered. Comparisons of the mixed nannofossil ages in the matrices with sedimentological and structural data suggest that sediment mixing resulting from fault movement is subordinate to that occurring during deposition.

Chemistry of magmatic samples of ODP Holes 134-832B and 134-833B

New petrographic and compositional data were reported for 143 samples of core recovered from Sites 832 and 833 during Ocean Drilling Program (ODP) Leg 134. Site 832 is located in the center and Site 833 is on the eastern edge of the North Aoba Basin, in the central part of the New Hebrides Island Arc. This basin is bounded on the east (Espiritu Santo and Malakula islands) and west (Pentecost and Maewo islands) by uplifted volcano-sedimentary ridges associated with collision of the d'Entrecasteaux Zone west of the arc. The currently active Central Belt volcanic front extends through the center of this basin and includes the shield volcanoes of Aoba, Ambrym, and Santa Maria islands. The oldest rocks recovered by drilling are the lithostratigraphic Unit VII Middle Miocene volcanic breccias in Hole 832B. Lava clasts are basaltic to andesitic, and the dominant phenocryst assemblage is plagioclase + augite + orthopyroxene + olivine. These clasts characteristically contain orthopyroxene, and show a low to medium K calc-alkaline differentiation trend. They are tentatively correlated with poorly documented Miocene calc-alkaline lavas and intrusives on adjacent Espiritu Santo Island, although this correlation demands that the measured K-Ar of 5.66 Ma for one clast is too young, due to alteration and Ar loss. Lava clasts in the Hole 832B Pliocene-Pleistocene sequence are mainly ankaramite or augite-rich basalt and basaltic andesite; two of the most evolved andesites have hornblende phenocrysts. These lavas vary from medium- to high-K compositions and are derived from a spectrum of parental magmas for which their LILE and HFSE contents show a broad inverse correlation with SiO2 contents. We hypothesize that this spectrum results from partial melting of an essentially similar mantle source, with the low-SiO2 high HFSE melts derived by lower degrees of partial melting probably at higher pressures than the high SiO2, low HFSE magmas. This same spectrum of compositions occurs on the adjacent Central Chain volcanoes of Aoba and Santa Maria, although the relatively high-HFSE series is known only from Aoba. Late Pliocene to Pleistocene lava breccias in Hole 833B contain volcanic clasts including ankaramite and augite + olivine + plagioclase-phyric basalt and rare hornblende andesite. These clasts are low-K compositions with flat REE patterns and have geochemical affinities quite different from those recovered from the central part of the basin (Hole 832B). Compositionally very similar lavas occur on Merelava volcano, 80 km north of Site 833, which sits on the edge of the juvenile Northern (Jean Charcot) Trough backarc basin that has been rifting the northern part of the New Hebrides Island Arc since 2-3 Ma. The basal sedimentary rocks in Hole 833B are intruded by a series of Middle Pliocene plagioclase + augite +/- olivine-phyric sills with characteristically high-K evolved basalt to andesite compositions, transitional to shoshonite. These are compositionally correlated with, though ~3 m.y. older than, the high-HFSE series described from Aoba. The calc-alkaline clasts in Unit VII of Hole 832B, correlated with similar lavas of Espiritu Santo Island further west, presumably were erupted before subduction polarity reversal perhaps 6-10 Ma. All other samples are younger than subduction reversal and were generated above the currently subduction slab. The preponderance in the North Aoba Basin and adjacent Central Chain islands of relatively high-K basaltic samples, some with transitional alkaline compositions, may reflect a response to collision of the d'Entrecasteaux Zone with the arc some 2-4 Ma. This may have modified the thermal structure of the subduction zone, driving magma generation processes to deeper levels than are present normally along the reminder of the New Hebrides Island Arc.

Carta Executoria de hidalguía [Manuscrito] : a pedimento de Antón Gallego,[Alonso Gallego, Blas Mogollón y Miguel Gallego, hermanos y vecinos] de la villa de la Puebla de Alcocer

Alcance y contenido: Executoria de hidalguía, iniciada en 1565, a favor de Antón Gallego, Alonso Gallego, Blas Mogollón [Blas Gallego Mogollón] y Miguel Gallego, y que resolvía el pleito que tenían estos con el Concejo de la villa de la Puebla de Alcocer (Badajoz), demostrándo su nobleza y limpieza de sangre y por tanto, declarándoles exentos de "pechar ni contribuir en los pechos y derramas reales y concejales ... de que eran libres y esemptos los hombres hijos dalgo"

Rmi. P.F. Antonij a Spiritu Sancto ... Directorium Confessariorum ... partes duae ... : accessere suis locis relatae passim sententiae dammate à SS. Pontif. Alexandro VII, [et] Innocentio XI /

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Calendario manual para el año de 1820, bisiesto : vigesimo sexto que arregla al meridiano de Mexico /

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Respuesta satisfactoria a la carta apologetica, que escribieron el Lic. D. Manuel Antonio Moreno, y el B.r D. Alejo Ramon Sanchez, y defensa contra la censura, que en ella se hace, de algunas proposiciones contenidas en la Intruccion sobre el remedio de las lagartijas /

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Obras espirituales del venerable padre Luis de la Puente, de la Compañía de Jesus ...

Vol. 1-2: Parte [primera-]segunda, Contiene todos los mysterios de la Passion de Jesu-Christo ... hasta la venida del Espiritu Santo y publicacion del Evangelio.

Medulla theologiae : pro triennali cursu in tres partes commode distributa ... /

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Medulla theologiae : pro triennali cursu in tres partes commode distributa ... /

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Tesoro catolico y moral : en que hallaran los fieles muy explicado todo lo que han de procurar saber, y entender, para creer, y obrar lo que se contiene en toda la doctrina christiana ... /

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Medulla Philosophiae : pro triennali cursu in tres partes commode distributa : celeberrimae Iesuiticae Scholae principiis solidè stabilita... /

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Dios prodigioso en Teresa de Iesus niña que murio a los cinco años vn mes y diez y siete dias de sue [!] edad /

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El prodigo santo y corona regia : deducido de la diuina Escritura y doctrina de los sagrados doctores, y varones ilustres en materias de espiritu /

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