bluuebunny/crossref_metadata_2025 huggingface dataset:
Utilisation du dosage de l'uranium, par fluorometrie, dans l'etude du Paleogene continental du seuil du Poitou
Authors: Steinberg Michel
Published: June 2020

Differences in the tenor of uranium, soluble in 2.5 N nitric acid, from different beds of the Paleogene continental sedimentary deposits in the Poitou strait in western France suggest two distinct sources of the uranium. Clays derived from erosion of Mesozoic limestones are very poor in uranium, but an appreciably greater content characterizes the transported detrital deposits derived from erosion of the central massif and the Gatine hills of Vendee.
Contribution a l'etude des formations plio-quaternaires des Alpes-Maritimes
Authors: Siffre Michel
Published: June 2020

The Pliocene formations of the lower valleys of the Siagne and Argentiere rivers in the Maritime Alps of southeastern France are Plaisancian (lower Pliocene). Several facies are present. Labradorite-andesites of the Aspres hills between Biot and Villeneuve-Loubet, including both flow rocks and pyroclastics, are also Plaisancian as they are intercalated in shales of that age. Fossil wood occurs in the pyroclastics; one tree trunk is nine meters long by 50 centimeters thick. The principal Quaternary deposits in the Siagne valley are marine sands and clays overlain by black lagoonal clays. The Argentiere valley is characterized by fluviatile deposits.
Le renouveau des etudes europeennes sur les volcans actifs
Authors: Geze Bernard , Tazieff Haroun
Published: June 2020

Recent studies on the active volcanoes of the world are briefly outlined. Forty-two publications resulting from research by French scientists and by the National Center of Volcanology of Belgium during the last few years are listed in the bibliography.
Elaboration d'une stratigraphie paleomagnetique des formations volcaniques
Authors: Roche A.
Published: June 2020

From the analysis of the natural magnetism of rocks, a component--thermoremanent magnetism (T. R. M.)--can be isolated, which corresponds to the magnetism acquired by the rocks at the time of their formation. Results of observations based on the method show that the earth's magnetic field resembles the field created by a geocentric dipole, the axis of which, as related to the earth's crust, has changed considerably throughout geologic time. The intensity of the field has also varied although it is not certain to what degree. Observation of the nature and direction of the rock magnetism shows that the trajectory of the geomagnetic axis, in the course of time, corresponds to a complex curve with numerous reversals and points of intersection. Figures for the declination and inclination of the magnetic field obtained from Precambrian to Quaternary rocks of France and other areas of western Europe indicate that magnetic inclination during the Silurian and Devonian and the Permian and Triassic was slight; that magnetic declination was more often to the east than to the west; and that in the Permian, Triassic and Cretaceous variations in direction were of little importance and reversals were numerous, while in the Carboniferous and Neogene there was considerable variation in direction with fewer reversals.
L'eruption volcanique de 1960 au Lopevi (Nouvelles-Hebrides)
Authors: Remy Jean Marcel
Published: June 2020

The first of four phases observed in the eruption on the western coast of Lopevi was marked by explosive activity during which the old crater reopened and a new crater, referred to as the upper crater, was formed. A smoke avalanche carrying scoria, lapilli, and cinders spread subhorizontally and represented the second phase. In the third phase, four lava flows containing jagged, scoriaceous blocks 10-50 cm in diameter were emitted from the base of the upper crater, covering part of the deposits of the smoke avalanche. The fourth phase was marked by the opening of several new vents characterized by activity involving the emission of either gaseous jets, alternating smoke wreaths and loud explosions, or gaseous clouds and lava flows from lower craters accompanied by a decrease in the activity in the upper crater. Petrographic analysis of the lavas shows that they are andesitic basalts containing plagioclase and forsterite phenocrysts and plagioclase microlites. Petrogenic evidence shows that the rocks of this eruption resemble the series of alkalic olivine-bearing basalts, and in some cases possess characteristics similar to the tholeiitic series.
La diversite des basaltes
Authors: Yamasaki Masao , Brousse Robert
Published: June 2020

By comparing the basalts from different areas, France and Japan in particular, two major groups can be distinguished--rhyolitic basalts and phonolitic basalts. Subdivisions recognized in each group represent the median points in the progressively changing suite of the basaltic lavas. The rhyolitic basalts are divided into four categories--tholeiites, high-alumina basalts, trachybasalts, and trachybasalts of the Puys chain. The phonolitic basalts are characterized by their poor silica content, giving rise to the crystallization of olivine and nepheline (basanites). This group includes the olivine-basalts of the Pacific and of Mont-Dore (France). Comparison of the mineral content of the basalts shows that they contain progressively larger amounts of dark minerals such as olivine and titano-augite in proportion to the diminishing silica content--a progression ending with the ankaramites, oceanites, and picrites. The theory that basalts are formed by the partial fusion of the peridotite mantle--those poor in silica at greater depths than the silica-rich--explains the continual variation in the chemical and mineralogical composition of the basalts studied. The shallower, rhyolitic magmas flow easily, dominating the larger volcanic complexes (Hawaii, Deccan, Mont-Dore, Cantal), while the deeper magmas, the basanites, form only rare batholiths of smaller proportions, as in Lorraine.
Dosage du potassium, de l'uranium, du radium et du thorium, par spectrometrie gamma dans les laves d'Auvergne, du Velay et de la province sicilienne
Authors: Cheminee Jean Louis , Nordemann Daniel
Published: June 2020

Fifty samples of volcanic rocks from south-central France, ranging from basalts to rhyolites, were subjected to gamma spectrometry analysis for the purpose of determining the proportions and relationships of the constituent radioactive elements. Zircon, sphene and apatite generally contained less thorium and uranium than the less abundant accessory minerals such as allanite, monazite and xenotime. Results of the analysis also show that the percentage of radioactive minerals is greater in the acidic lavas than in the intrusive rocks, suggesting that the latter were subjected to hydrothermal alteration. The percentage of potassium varies in direct proportion to the variation in the percentage of silica. The increase in thorium as a function of silica is more rapid than that of uranium. Graphically, no correlation exists between the percentage of radium and silica. The concentrations of uranium and thorium do not vary independently but seem to have a statistical dependence whose functional relations are not yet apparent.
Quelques particularites de la partie nord-ouest du volcan cantalien (region des Rhues et de la Sumene)
Authors: Roux Jean
Published: June 2020

The Miocene basalts at the base of Cantal volcano are exposed at approximately uniform heights in the valleys of the area, indicating that there ought to be a branching internal basaltic lava flow with an origin and extent similar to the upper Pliocene basalts of the plateaus. The igneous breccias in the Auzers area exhibit an abnormal thickness of 170 meters. The northwest part of the Moussage lava field, formed of the plateau basalts, is overlain by the Suc du Rond flows indicating that the Suc du Rond basalts, and not those of the plateau, represent the last phase of the Cantal eruption.
A propos de depots du Pliocene superieur et du Quaternaire sur la cote nord de l'ile de Minorque (Baleares)
Authors: Bourrouilh Robert , Magne J.
Published: June 2020

Remnants of upper Pliocene and early Quaternary formations have recently been discovered at the summit of the Atalaya promontory, the easternmost and highest of three promontories on the northern coast of the island of Minorca (Spain). Study of the beds indicates that the underlying Jurassic-Cretaceous formations were abraded and then subjected to karst erosion. The basal bed of the Pliocene-Quaternary sequence is a decalcification clay, the product of the karst phenomena. Overlying the clay is an organic limestone with abundant foraminifera and Microcodium indicative of littoral conditions produced by partial submergence of the northern coast. Two microbreccias, the upper more compact than the lower, overlie the organic limestone and also contain abundant foraminifera. The microbreccias are clearly marine littoral, evenly bedded below, crossbedded above, and the result of submarine currents. A lighter colored limestone petrographically identical to the lower organic bed overlies the microbreccias. Final uplift (probably Recent) produced the existing cliffs and exposed the Pliocene-Quaternary formations. The age of the sequence is tentatively assigned on the basis of the presence of Microcodium.
Nouvelles recherches sur le gisement villafranchien de Seneze (Haute-Loire, France)
Authors: Elha Henri , Grangeon Pierre
Published: June 2020

Examination of a section of the core taken from a boring in the center of the Villafranchian Seneze lake has provided additional data on this classic locality. Variations observed in the pollen content are used to delineate a series of four separate climatic oscillations of alternating temperate and cool periods. The deposits represented in the core were laid down during the Villafranchian in a fresh-water medium as indicated by the presence of pollen from fresh-water aquatic plants and from Botryococcus. Pollen diagrams are included.
La signification climatique fournie par les faunes malacologiques quaternaires en Bourgogne
Authors: Puissegur Jean Jacques
Published: June 2020

An abundant terrestrial molluscan fauna was collected from Genay and Flavigny-sur-Ozerain, Cote-d'Or, France. Both localities are underlain by Bajocian detritus overlying Liassic marls. Three principal faunas are recognized in the Genay deposits. The first fauna is characteristic of temperate conditions. The second fauna contains only a few species all of which show signs of adaptation to difficult conditions: alternating humid and dry periods. The third fauna contains numerous species including forest-dwelling forms, indicating the replacement of the Wuermian glaciation by the Atlantic climate. Other deposits provide similar results, demonstrating the variability and usefulness of molluscan faunas in relation to temperature and humidity.
Nouvel essai de correlation des terrasses rhodaniennes
Authors: Bonnet Andre
Published: June 2020

Reconstruction of the Quaternary terraces of the Rhone (southeast France) reveals three or possibly four levels between the Rhone delta and the Rhone-Drome confluence. The age of the lowest terrace level--best exposed at Valence-Romans and upstream--is questionable. It may represent either the Wuerm or the Riss, or it may be divided between two different stades--neo-Riss and an older stade represented by the Leore-Fouillouse terrace. The middle terrace is Rissian and the highest terrace represents the Villafranchian. This phenomenon of uplifted terraces seems to be related to an isostatic uplift of blocks to compensate for the load of glacial ice. The continuity and extent of this phenomenon would explain the relative positions of the terraces, the older higher than the younger. Cross sections are included which show the recognized terraces. A correlation chart presents the Quaternary stratigraphy of Scandinavia, the alpine regions, the Sahara, central Africa, and Australia, and includes the major archaeological divisions.
La sequence climatique wurmienne du gisement paleolithique de la Salpetriere (Remoulins, Gard)
Authors: Escalon de Fonton Max
Published: June 2020

Stratigraphic study of the prehistoric site in the Salpetriere shelter cave (southern France) has provided information which gives an indication of the Wuerm II-Wuerm IV climatic evolution. The Wuerm II is represented by thermoclastic gravels and eolian sands. Gully erosion on the surface of the uppermost gravel represents the warming trend of the Wuerm II-III interstade. Red sand and gravel in the Wuerm III beds owe their color to a karst clay corresponding to the warm interstade between the Wuerm IIIa and b. The Lascaux interstade between the Wuerm III and Wuerm IV is represented by eolian sands badly eroded by trenches and gullies. Gravelly sands in the upper beds of the Wuerm IV form talus deposits which represent cooler, less humid conditions. Another gravelly sand which overlies the Wuerm beds represents two phases of the Dryas II--a cool, dry phase followed by a phase of increasing humidity. Remnants of upper Paleolithic industries are also described.
Correspondance entre les couples erosion-sedimentation et pluvial-aride au Sahara nord-occidental
Authors: Chavaillon Jean
Published: June 2020

A climato-sedimentologic cycle is proposed on the basis of Villafranchian deposits in the northwest Sahara. The relationship between the erosion-sedimentation cycle and the pluvial-arid cycle is shown. The stratigraphy and sedimentation of the material composing the terrace deposits show an evolution toward increasing aridity, beginning with gravel deposits of a fluvial character and progressing toward typically arid sediments. The proposed cycle begins with a period of maximum aridity during which massive dunes cover the ancient terraces and hamadas, and debris from gravity erosion accumulates in cones. In the arid-pluvial transition period, humidity gradually increases, causing erosion of the slopes and debris cones. Maximum erosion occurs in the pluvial period. In the pluvial-arid transition period, sedimentation is at first fluvial, involving coarse-grained material, then loamy, and finally eolian. Lacustrine levels, crust formations and secondary rhythms are also recognized and briefly described. This cycle is confirmed by the prehistoric civilizations from the Pebble Culture to the Neolithic.
Age et position des calcaires de Saint-Jean-de-la-Riviere dans le Cambrien des Moitiers d'Allonne (Manche)
Authors: Dore Francis
Published: June 2020

The type section for the Saint-Jean-de-la-Riviere limestone outcrops on the Moitiers d'Allonne anticline in the Douits valley north of Carteret and east of Moitiers (France). The limestones are younger than the sandy shale of the Cap Carteret series and between Moitiers and Bosquet the sequence is overlain by shales and red sandstones separating it from the Armorican sandstones. The lower Cambrian of the area presents a complete sedimentary section ending with a red sandstone facies of a regressing sea. A significant hiatus is evident before lower Ordovician transgression and continued deposition. Hyolothides and sponges, believed to be Azoic (early Precambrian) and older than Archaeocyathidae and Bigotina, are found in calcareous sandstone nodules on the beach at Carteret.
Essai sur la paleogeographie post-triasique et l'evolution secondaire et tertiaire du versant sud des Alpes orientales (Alpes meridionales; Lombardie et Venetie, Italie; Slovenie occidentale, Yougoslavie)
Authors: Aubouin Jean
Published: June 2020

The southern Alps are divided into five distinct zones formed during the geosynclinal stage: the Lombardian depression, the Tridentine ridge, the Belluno depression, the Friuli ridge, and the Julian depression. Transition zones can be defined between the units. Late geosynclinal deposition (Miocene) is best represented in the Friuli ridge zone. Post-geosynclinal deposition corresponding to Pliocene-Quaternary deposits is equivalent to that of the Po river plain. Geosynclinal and late geosynclinal evolution was marked by folding perpendicular to earlier tectonic trends. Post-geosynclinal folding (Pontian to Pliocene) was oblique or perpendicular to the preceding structural patterns. A correlation is made between the southern Alps and the Italian Dinaric Alps north of Lombardy and Venice; the geosynclinal deposits are correlated with the Dinaric molasse sequence; and post-geosynclinal events are related to the Po plains. It is believed that the eastern Alps are the 'true' Alps whereas the western Alps are a part of the Italian Dinaric Alps.
Etude geologique de la region de Castello-Tesino (Alpes meridionales, province de Trente, Italie)
Authors: Rasplus Leopold
Published: June 2020

The sedimentary series of the Castello-Tesino region in the eastern Venetian Prealps comprise a sequence of marine rocks ranging in age from the Liassic to Miocene. The Liassic gray limestones and the Dogger ooelitic limestones are neritic or subreefal deposits. The Malm and the Cretaceous deposits indicate a deepening of the sea. The Eocene and Oligocene facies are more terrigenous, but in the Lutetian, Priabonian, and Oligocene become littoral. The Miocene marks the transgression of a neritic sea indicated by the accumulation of a slightly discordant molasse sequence. The folds trend in a WSW-ENE direction. The stratigraphy and paleogeography indicate that the region belongs to the Belluno zone between the zone of Friuli to the east and the zone of Trento to the west.
Description d'une succession lithologique avec niveaux-reperes dans les schistes cristallins des Cevennes pres de Villefort (Lozere)
Authors: Brouder Paul
Published: June 2020

In the Villefort region of south France, crystalline schists are inclined along a fold trending northeast-southwest and overturned toward the northwest. The series is composed of conglomeratic gneiss and mica schist. Distinct horizons of amphibolite, quartzite, mispickel gneiss, and zoisitic gneiss are included. Many of these beds are persistent and valuable on a regional scale as marker horizons.
Resultats de sondages recents a Lyon
Authors: Russo Philibert
Published: June 2020

The results of a study on the detrital deposits at Lyon (France) prove the existence of post-Oligocene river courses in the city and its environs. Poorly rounded material was eroded from the Central Massif during the Miocene.
Le Cambrien et la base de l'Ordovicien dans la partie orientale et meridionale du Tafilalt (Maroc)
Authors: Destombes Jacques
Published: June 2020

A recent structural study of the Tafilalt area (Morocco), including a correlation study between the El-Aness and Ouzina sections, showed that the Cambrian units at the two localities are correlative and can be divided into two series--the Georgian series characterized by detrital material and arkosic beds, and an upper Acadian series which is thicker than the lower series. The lower Ordovician is characterized by a red sandstone horizon representing the upper Tremadoc transgression, and overlain by the lower Arenig series of green shales with graptolites. Between the Arenig and Tremadoc is a green glauconitic bed. It can be deduced that deposition decreased from south to north during Acadian and Georgian time. The seas did not reach the El-Aness massif during the Tremadoc but only during the lower Arenig.
Remarques sur Posidonomya dalmasi Dumortier du Jurassique de l'Ardeche
Authors: Freneix Suzanne
Published: June 2020

The pelecypod species Posidonomya dalmasi which was previously considered a synonym of Posidonomya ornati is now assigned to the genus Silberlingia on the basis of material collected from the Privas mines (France). The range of Silberlingia is therefore extended into the Callovian.
Observations sur le subbetique au sud de Calasparra (prov. de Murcie, Espagne)
Authors: Paquet J.
Published: June 2020

The Subbetic group, along the Calasparra meridian between the autochthonous Prebetic to the north and the basal Triassic of the Subbetic to the south, is divided into seven tectonic units. The Prebetic is characterized by continental, lagoonal, and neritic facies. The Puerta unit consists of Tertiary facies intermediate between the Prebetic and the Subbetic units to the south. The Los Rameles unit--northernmost Subbetic--consists of Jurassic-Eocene facies, the Cretaceous and Tertiary units being intermediate between the Puerta and Loma de Solana units. In the Loma de Solana unit (Jurassic-Oligocene) the Malm contains red bedded nodular limestones passing into upper Oxfordian and Tithonian marls. The Sierrecica de las Cabras unit contains Neocomian and Barremian beds which overlie the basal Triassic and underlie the Loma de Solana unit. The Sierra de Burete unit contains Jurassic-Paleogene beds intermediate between the Loma de Solana and Sierrecica de las Cabras units. The Sierra de Ponce unit contains Jurassic-Miocene strata representing the southern Subbetic. The recognition of these units makes it necessary to abandon the terms northern and southern Subbetic in this area.
Position stratigraphique des phosphates en Syrie
Authors: Atfeh Seifuddin A. , Faradjev Vladimir A.
Published: June 2020

Hydrologic investigations and field reconnaissance for the 1:50,000 scale map of Syria provided more detailed information on the exact stratigraphic position, quality, and extent of the phosphate deposits. The deposits are found in strata of Santonian through Eocene age, as well as in Holocene deposits in the southern part of the region. Santonian phosphates are limited to the central part of the southern Palmyride chain. Campanian phosphorites are well-developed and represented by rocks primarily composed of calcium phosphate. The major Maestrichtian phosphate deposits occur in the southern Palmyrides. Lower Danian phosphate is known only in the Ghadir el-Hamal. Paleocene phosphates are found on the flank of Mount Abou Rabah and Jabal Ash-Sheikh. Middle Eocene phosphorites are found in thin, localized bands, and in carbonate and glauconite beds. Upper Eocene phosphorites also occur in the southern Palmyrides. Holocene phosphates are represented by phosphatized bone accumulations.
Les Ceriopora neogenes (Bryozoaires cyclostomes) de la collection Michelin
Authors: Fischer J. C. , Buge Emile
Published: June 2020

The discovery and subsequent reexamination of the holotype and paratypes of Chaetetes pomiformis Michelin show that the specimens can be divided among three species, all of which are here described and figured: Ceriopora balavoinei Buge (=Chaetetes pomiformis), Ceriopora tumulifera (=Chaetetes pomiformis var. mamillosa), and Ceriopora hardouini n. sp. The new species was collected from the Tortonian of Vaucluse (France), and is characterized by the complete lack of diaphragms.
Contribution a l'etude seismologique du volcanisme de l'Herault et des Causses
Authors: Allegre Claude , Doussaint Louis , Mechler P. , Proust Francois
Published: June 2020

An initial series of experiments was made concerning seismic reception in the Languedoc region of southern France. The M-discontinuity is at relatively shallow depth (25 km) beneath these old volcanoes. Basalt is at 19 km depth. Some relationship may exist between this region of crustal thinning and the crystalline axes of Montagne Noire and the Pyrenees.
Observations sur les formations du continental terminal et du Quaternaire dans le bassin du Logone (Tchad)
Authors: Bouteyre G. , Cabot Jean , Dresch Jean
Published: June 2020

The rock series in the Logone and Lame basins in the southern Sahara is a crystalline basement complex, a series of Mesozoic formations culminating in the Benoue marine Cretaceous transgression in the western part of the region, the Pala and Kelo sandstone with lateritic zones, and Quaternary surficial deposits. The Mberi-Begangber-Koro erosion surface of Villafranchian (?) (late Pliocene) age is prominent in the region.
Elimination des produits d'alteration des roches anciennes avant leur examen en lames minces
Authors: Boyer Claude , Brousse Robert
Published: June 2020

There are several promising methods of removing alteration products from thin sections of rocks. The reagents used are hydrochloric, sulfuric, and nitric acids, distilled water, and oxygenated hot water. Some methods result in decreased clarity, but others suggest that further refinements may yield excellent results. Particularly good results are obtained with ferruginous pigmentation subjected to hydrochloric acid.
Les nappes alluviales des cours fossiles du Gave de Lourdes dans leur partie aval
Authors: Alimen H. , Maggion Roseline
Published: June 2020

The downstream portions of the Quaternary terraces of the Gave de Lourdes river, Hautes-Pyrenees, southwestern France, are assigned Donau, Guenz, and Mindel age on the basis of their respective positions, their continuity with the dated Bigorre terraces, the nature of their paleosols, and the petrographic characteristics of their cobbles.
Existence de filons ignimbritiques au sud de la caldera de Maure-Vieille, Esterel oriental (Alpes-Maritimes)
Authors: Boucarut Marc
Published: June 2020

The southern flank of the Maure-Vieille caldera of the Esterel massif of the Maritime Alps in southeastern France is remarkable for the large number of ignimbrite dikes in the series of alternating sedimentary and volcanic rocks of Permian age. Three types of dikes occur. The first is a rhyolitic rock poor in quartz and sanidine phenocrysts, but with abundant oriented laths consisting of a spherulitic quartz-potassic feldspar nucleus enclosed in an aureole of feldspar dusted with iron oxide. These 'fiammes' are devitrified fragments of pumice. The second type is of similar material but is brecciated in fragments cemented by a rhyolitic matrix. The third type is vitroclastic in structure with iron oxide inclusions, but completely devitrified. The rhyolite of the area is the same chemically as the ignimbrite, and the dikes of ignimbrite represent pyromagmatic fragmentation occurring in the conduits through which the rhyolite was erupted.
Sur la presence d'algues calcaires dans le Carbonifere de differents bassins sahariens (Colomb-Bechar, Reggane, Polignac)
Authors: Chanton Nicole
Published: June 2020

Marine Carboniferous algae in the Colomb-Bechar, Chebbi, El Ahmar, Ohanet, and Polignac basins of the Sahara are present in greater numbers than had been supposed. Although they are good facies indicators, they are not suitable for regional zonation, and their stratigraphic value is very limited. Dasycladaceae of the genera Anthracoporellopsis, Koninckopora, and Macroporella, and Rhodophyceae of the genus Petschoria are numerous. The genera Anthracoporellopsis and Petschoria elsewhere are known only in the Ural region of the USSR. Koninckopora and Macroporella are known from various parts of Europe, Asia, Africa, and America.
Caracteres generaux de la biogeographie de l'U.R.S.S. pendant la periode carbonifere
Authors: Einor O. L. , Voynovskiy-Kriger K. G. , Vasilyuk N. P. , Vdovenko M. V. , Gorak S. V. , Dunayeva N. N.
Published: June 2020

Analysis of the geographic extent of faunas in the Carboniferous seas of USSR has provided general characters for defining biogeographic provinces in the area. Two provinces are distinguished in the lower and middle Carboniferous seas. The Europe-Tien Shan province is divided into regions including the Ukraine-Donets, eastern USSR, Ural, Transcaucasus, and Tien Shan regions. The Kazakhstan-Siberia province includes the regions of Kazakhstan, Altai, Kuznetsk basin, Transbaikalia, Taimyr, Kolyma-Koryak, Mongolia, Sikhote-Alin. In the upper Carboniferous, following a major regression, the differences between the marine faunas of Europe and Central Asia increased to such a degree that the corresponding basins must be considered independent provinces--eastern Europe, Tien Shan, eastern Siberia, and the Pacific Ocean. The data presented are based on published material.
Variations de teneurs en Cu, Ni, Cr, Co et V dans quelques roches volcaniques des Causses et du Bas-Languedoc
Authors: Dupuy Claude
Published: June 2020

Fourteen samples from the Causses and Bas-Languedoc volcanics, including a peridotite nodule, basaltic lavas, and pegmatoids, have been submitted to geochemical analysis for the first time, in order to determine the distribution of Cu, Ni, Co, and V. In the rocks studied, these elements decrease in percentage during the course of differentiation with the exception of Cu, whose percentage is not affected. The decrease of the Ni/Co ratio to below 1 suggests that Ni was removed more quickly from the magma than was Co. Median percentages calculated for the basalts indicate that the presence of olivines is accompanied by a marked enrichment of Ni, Co, Cr, and Cu.
Apercu general sur les depots eocenes de la Belgique
Authors: Gulinck Marcel
Published: June 2020

Tertiary sedimentation in the Belgium basin began with the Montian. The Heersian is retained as a separate stage to include provisionally the Gelinden marls and the Infraheersian. This recommendation is based on the unique paleontologic character of the stage and its complete separation from the overlying Landenian shales. The Eocene developed to its greatest extent during the Landenian with the successive deposition of shales, silts, tuff, sands, marls and lignites. The Ypresian-Landenian boundary is defined by the first appearance of marine facies above Landenian fluviomarine deposits. The Panisilian may need revision as it now includes Nummulites planulatus. The hiatus between the overlying Bruxellian and the Ledian is not as significant as first thought since the Ledian is correlated with upper Lutetian in the Paris basin. The Bartonian immediately succeeds the Ledian. The Tongrian in northern Belgium is not a lateral equivalent of the Bartonian.
Etude biometrique et statistique de Nummulites laevigatus Bruguiere dans les bassins de Paris et du Hampshire; implications stratigraphiques
Authors: Blondeau A.
Published: June 2020

Biometric and statistical analysis of approximately 4500 specimens of Nummulites laevigatus from the Paris basin and from Hampshire (Wight, England), indicates that this species belongs to the lower Lutetian (Eocene), and that the enclosing beds are equivalent to the Bracklesham and the Fisher beds VI and VII of England and the Bruxellian of Belgium. N. laevigatus forms only one biozone. Among the results of the study are the recognition of a diminishing frequency in the irregularity and loose coiling of the spire in favor of regularity and tight coiling, from the base to the top of the lower Lutetian, and the dominance of flattened forms in the older lower Lutetian outcrops.
Les laves et les pegmatitoides du volcan des Rives (Herault)
Authors: Remy Jean Marcel
Published: June 2020

The lavas of the Rives volcano are ankaramites, having flow structure with phenocrysts and microlites of olivine and clinopyroxene. The Rives pegmatitoids are light, crystalline rocks containing olivine with the same optical properties as that of the surrounding lavas. The structure of the rocks is rather complex, the pyroxenes and olivine being corroded by salic minerals. The chemical analyses of the minerals found in the lavas and in the pegmatitoids are compared. The primary cause of the pegmatitoid differentiation may be the presence of a volatile compound whose concentration does not result from normal magmatic evolution, and which resulted in the formation of differentiated alkalic rocks. The Rives pegmatitoids are clinopegmatitoids.
Quelques donnees stratigraphiques sur le Silurien des confins algero-marocains (Ben Zireg, Djebel Grouz et regions voisines)
Authors: Jaeger Hermann , Massa Dominique
Published: June 2020

Silurian outcrop zones are limited, in the Colomb-Bechar basin, to the Ben Zireg anticline and to exposures resulting from the southern Atlas flexure and bordering faults (Hassi-el-Diab, Teniet-Ghenia). In the area, the Valentian is missing; the Wenlock is transgressive; the Ludlovian is very thin, beginning with the Monograptus deubeli zone; the upper Budnanian and basal Lochkovian (M. uniformis, M. praehercynicus horizons) are present. The Emsian overlies basal Lochkovian beds or lowest Lochkovian, with the Siegenian missing. In general, in the northeast part of the Colomb-Bechar basin the Silurian thins rapidly from south to north. At Hamar Lagdad the Silurian is also condensed; the lower Silurian interval, transgressive on the Caradocian, is upper Valentian; Kopanina and Pridoli equivalents are present while the Lochkovian is represented by intraformational cineritic tuffs which underlie the Hamar Lagdad bioherm (Emsian).
Importance des constructions algaires dues a des cyanophycees dans les formations continentales du Cretace superieur et de l'Eocene du Languedoc
Authors: Freytet Pierre , Plaziat Jean Claude
Published: June 2020

The upper Cretaceous and lower Tertiary continental sediments of the Languedoc region, in southern France, contain numerous fossil algal structures of various shapes and sizes, previously supposed to be concretions. The algae principally represented are forms with affinities to living Rivularia haematites of the Cyanophyceae. The morphology of the structures varies with the mode of deposition. Forms subject to flood currents are algal balls and incrustations on shells. Those in calmer zones are characterized by larger cylindrical forms.
Sur la position stratigraphique des gres de Gassa (Niger occidental)
Authors: Machens Eberhard , Reichelt Rudolf
Published: June 2020

The Gassa sandstone near Tillaberi in western Niger, shown on the 1960 geologic map of western Africa (l:2,000,000) as provisionally assigned to the Paleozoic, is an Infracambrian formation deposited on the Precambrian basement and overlain by the Infracambrian Ydouban group. The Gassa sandstone thus is the stratigraphic equivalent of the Firgoun sandstone in the Gourma basin.
Sur la microfaune du gisement lutetien de Puits-Neuf, commune de Bois-de-Cene (Vendee); etude paleontologique et paleogeographique
Authors: Margerel Jean Pierre , Ters M.
Published: June 2020

A rich foraminiferal and ostracod fauna occurs in Lutetian (Eocene) deposits near Puits-Neuf in the Verie river valley, western France. The fauna is of latest Lutetian age and indicates a littoral environment.
Sur la presence de dolomite dans les 'terres noires' de l'anticlinorium de Laragne (Hautes-Alpes); interpretation paleo-oceanographique
Authors: Artru Philippe
Published: June 2020

Middle Jurassic (Bathonian) and upper Jurassic (Callovian-lower Argovian) dark-colored shales and marls of Hautes-Alpes, France, locally known as the 'terres noires,' contain abundant microcrystalline dolomite in the lower (Bathonian) part. Mixed detrital sediments and carbonates in the lower part contrast with essentially terrigenous strata in the upper (Callovian-Oxfordian) part. The Bathonian depositional basin was isolated by sills and probably contained magnesium-rich waters of low pH; at the beginning of the upper Jurassic the basin became more open and dolomite formation ceased.
Sur la geologie de l'Egee; regard sur la Crete (Grece)
Authors: Aubouin Jean , Dercourt Jean
Published: June 2020

The oldest rocks exposed on Crete (Greece) are Paleozoic? metamorphic rocks. Five series are represented in the overlying sedimentary cover, whose deposition took place in a geosynclinal environment from Triassic to Eocene time. Molasse deposits are the principal representatives of the late geosynclinal phase (Miocene); marls and limy sandstones and conglomerates were formed during the postgeosynclinal phase (Pliocene). Major faults are the dominant tectonic feature of the island. Two nappes are identified: the Pindus nappe on which the ophiolitic (sub-Pelagonian) nappe is superimposed in places. Differential uplift and intense normal faulting have broken the island into a number of massifs separated by lowlands.
Metallogenie du massif de l'Arize
Authors: Perseil Elena Adriana , Tourenq Claude
Published: June 2020

A map is presented of the metallic deposits of the Arize massif (French Pyrenees). Particular emphasis is given to Paleozoic sulfide veins associated with the Foix granite and the deposits near the basement contact at the northern border of the massif. The deposits associated with the Foix granite reflect hydrothermal zonation related to satellite veins of the granite. Lead-zinc and copper deposits along the Arize massif borders are associated with faults and occur as veins, veinlets, or impregnations.
La metallogenie de la France
Authors: Laffitte Pierre
Published: June 2020

A regional metallogenic study of the ore deposits of France in relation to their geologic settings is presented. Twenty-three areas, subdivided into 100 districts, are thus defined and 300 deposits or possible deposits are categorized. Five metallogenic provinces are suggested. Two formed during the Hercynian (late Paleozoic)--the Gaules and the Sardo-Provencal; a fractured border; an internal Alpine zone; and a Pyrenean trough. Particular attention is given to regional zonation which is manifested in the chemistry of the successive Paleozoic mineralizations. The fracturing of the crust prior to the Caledonian (early Paleozoic) is discussed. Examples are presented of the relation of ore deposition to tectonics.
Donnees nouvelles sur les terrains paleozoiques de l'Argentella-Tour Margine (Corse); attribution a la limite devono-carbonifere du calcaire de Capitello
Authors: Krylatov Serge; Mamet
Published: June 2020

The series of rocks which unconformably overlies an older metamorphic series of the Argentella-Tour Margine area, northwestern Corsica (France), is primarily composed of detrital sedimentary formations, some of which contain elements suggesting volcanism, also represented by albitophyric flows. This series, considered as Dinantian (lower Carboniferous) until now, is, in fact, older. The Capitello limestone, capping the series, contains foraminiferal assemblages whose position in the Avesnois reference series is well known as the Famennian-Tournaisian (Devonian-Carboniferous) boundary. As the major part of the sedimentary series is older, the Devonian must be extensively represented.
Un episode des eruptions sancyitiques du Mont-Dore enregistre a Coudes (Puy-de-Dome)
Authors: Bout Pierre
Published: June 2020

In several localities of the Puy-de-Dome department (Central Massif, France) fluvial deposits with pumice, ash, and volcanic minerals outcrop. Study of the mineral composition of these outcrops establishes close analogies among them and makes it possible to tie in their volcanic minerals with a single period of acidic activity of the Mont-Dore volcano. The mammalian fauna in the contemporaneous alluvium is middle Pleistocene; paleomagnetic determinations and K/Ar dates on the flows verify this age.
Contribution a l'etude des gisements volcano-lacustres a diatomees de la region de Rochessauve et de Saint-Bauzile (Ardeche)
Authors: Ehrlich Aline
Published: June 2020

The upper Miocene diatomaceous sediments of the northeast border of the Coiron massif (Ardeche, France) indicate a shallow-water lacustrine environment. Until now the outcrops at Andance and Ranc-Le Combier have been considered as part of the same lacustrine deposition, but paleoecologic studies suggest that they formed independently. At Andance, diatomaceous sedimentation was continuous until the eruption of the Coiron plateau basalts, while at Ranc a hiatus occurs between the lower and upper diatomites.
Donnees geophysiques sur la structure profonde du Diois et des Baronnies
Authors: Flandrin Jacques , Weber Christian
Published: June 2020

Aeromagnetic and gravimetric studies made in the region of the Diois and Baronnies mountains (French Prealps) indicate a clear relation between deep structure and many surface structures. In particular, the basement took part in three displacements, the two great north-south faults of Saillans-Merindol and Die-la Motte-Chalancon, and the northeast-trending Clery fault. On the other hand, the east-west folds affecting the Mesozoic and Tertiary are definitely shallow decollements in which the basement did not participate.
A propos des conglomerats antenummulitiques des Alpes de Provence
Authors: Lapparent Albert F. de
Published: June 2020

Some stratigraphic observations lead to assignment to the lower Eocene of the pre-Nummulitic conglomerates frequently developed between the Cretaceous and the Eocene in the Alps of Provence [France]. These 'Argens conglomerates' or 'Microcodium conglomerates,' as they are still called, are of continental origin and very different from the upper Cretaceous.
Jacques Bourcart (1891-1965)
Authors: Brunn Jan H.
Published: June 2020

The career of Jacques Bourcart, who died June 24, 1965, is retraced. After a number of classic geologic works, particularly in Morocco, he became a renowned specialist in submarine geology. A list of his works is given.
Esquisse geologique de la peninsule Rallier du Baty, archipel de Kerguelen, terres australes et antarctiques francaises
Authors: Nougier Jacques
Published: June 2020

The geologic structure of the Rallier du Baty peninsula (Kerguelen islands) is characterized by basaltic flows with an andesitic tendency, intruded by a volcano-pluton of quartziferous syenites which metamorphosed the basalt near its contacts. Recent superimposed acid volcanism is present, and fumarolic activity has been noted on the west coast.
Quelques observations sur les rapports des filons a antimoine des environs du Collet-de-Deze (Lozere) avec leur environnement geologique
Authors: Roger Guy
Published: June 2020

Mapping of a sector [of France] situated south of Mont Lozere (central Cevennes) shows that antimony veins are localized in horizons rich in quartz, feldspars, and sometimes calcic minerals, and never in mica schists rich in phyllites. This control is valid only for stibnite veins, and not for lead-zinc veins. All of these massive layers include various sulfides, usually disseminated, sometimes in thin beds or small veinlets, without apparent connection to the veins or fissures. Problems concerning the origin of these disseminated sulfides and their relations to the veins are posed.
Macroforaminiferes de l'Eocene de Colombie
Authors: Butterlin Jacques
Published: June 2020

Some species of macroforaminifera from the middle and upper Eocene, described for the first time from Colombia, are illustrated. The polymorphism of Helicostegina polygyralis (Barker) is shown, as well as the change in form of Nummulites willcoxi Heilprin in the course of its growth.
Presence du genre Gagaria (echinide regulier temnopleuride) dans l'Eocene moyen de la vallee du Senegal
Authors: Elouard P. , Roman Jean
Published: June 2020

The genus Gagaria, known in the Eocene of the Indian peninsula, is noted for the first time in the lower Lutetian of the Senegal-Mauritania sedimentary basin. It is represented by G. foutatoroensis n. sp., whose mode of occurrence is defined. Comments on the associated fauna and on the environment where this species must have lived are given. G. foutatoroensis is interesting because of its relationships with several genera (Thylechinus, Orthechinus, Triplacidia) existing at the same time, especially in Senegal and Egypt.
Gisements nouveaux de la faune cernaysienne (mammiferes paleocenes de France)
Authors: Russell Donald E. , Louis Pierre , Poirier Max
Published: June 2020

Paleocene mammals have recently been discovered at two new localities, one in a shell-bearing lentil exposed near Berru and the other in marls at Rilly-la-Montagne (Marne, France). From the specimens collected, knowledge of the anatomy of several species has been improved. Bessoecetor? levei n. sp., Remiculus? n. sp., and an unnamed new genus and species of the Arctocyonidae are established. Comparison with the classic locality at Cernay (near Rheims) is difficult due to an insufficient number of complete fossils.
Sur l'existence et l'age des deux phases regionales de metamorphisme alpin dans les zones internes des Hellenides en Macedoine centrale (Grece)
Authors: Mercier Jacques
Published: June 2020

Two regional phases of alpine metamorphism developed contemporaneously in the inner zones of the Hellenides: the first phase was after the Triassic, probably in the upper Jurassic, and earlier than the upper Maestrichtian or even the Aptian-basal Albian; the second phase was after the upper Maestrichtian but before the lower Oligocene, probably in the Priabonian. In addition, a phase of dynamic metamorphism was manifest locally in the foreland of the Serbo-Macedonian massif, in volcanic and tuffaceous formations of middle-upper Eocene age; it was contemporaneous with the late Priabonian tectonic phase. Hercynian and pre-Hercynian cores are both represented in the inner Hellenides and were affected by the alpine metamorphism.
Etude geologique de la region de Come et de la Brianza occidentale (Alpes meridionales, Italie)
Authors: Vicente Jean Claude
Published: June 2020

The sedimentary series of the Como-Brianza region is exclusively marine, represented by formations of Jurassic to Pliocene age which are divided into three groups by two major unconformities, in the Oligocene and Pliocene respectively. Wide facies variations are characteristic of the series, notably the calcareous-siliceous deposits of the Jurassic and the upper Cenomanian and middle Campanian flysch deposits. The sediments are similar to those of the Lombardy trough. The three groups of formations represent stages in the paleogeographic evolution of the area: geosynclinal (Jurassic-lower Tertiary), late geosynclinal (Oligo-Miocene), and postgeosynclinal (Pliocene).
Brachiopodes et stratigraphie du Lias, pres d'Os de Balaguer (Lerida, Espagne)
Authors: Bulard Pierre Francois , Delance Jean Henri
Published: June 2020

Triassic-Cretaceous sediments, brachiopod-molluscan faunas, Domerian and lower-middle Toarcian biofacies
Les edifices stromatolitiques precambriens de la 'serie a stromatolites' du nord-ouest de l'Ahaggar (Sahara)
Authors: Bertrand Janine
Published: June 2020

Conophyton with digitations, branching columnar colonies (six forms), intermediate growing forms, facies variations, ecology, Algeria
Contribution a la stratigraphie de l'Eocene nord-aquitain
Authors: Ducasse Odette
Published: June 2020

Subsurface sections, ostracod fauna, Eocene-Oligocene, France
Traits principaux de la tectonique postnappe dans les Babor occidentaux (region de Bougie, Algerie)
Authors: Leikine Michel
Published: June 2020

Asymmetric folds, post-Lutetian-pre-Numidian (Eocene) compression, Numidian thrusting, post-Numidian compression (post-Burdigalian)
Etude palynologique de l'Infralias de la peripherie du Morvan et comparaison avec les autres bordures du Massif Central
Authors: Lesage Marie Therese
Published: June 2020

Rhaetian-Hettangian associations of northeastern and eastern Morvan and south-southeastern Central Massif, Hettangian associations of western Central Massif, stratigraphy, paleogeography, France
Quelques precisions sur le Callovien du Chatillonnais
Authors: Thierry Jacques
Published: June 2020

Jurassic, ammonite fauna, France
La terminaison occidentale de la Kabylie des Babor (region d'Akbou); remarques sur la notion d'extrusion
Authors: Coutelle Alain
Published: June 2020

Triassic-Cretaceous lithostratigraphy, structural features, two narrow dislocated anticlines separated by a flat-bottomed syncline, review of various usages of the term tectonic extrusion, Algeria
Reconnaissance geologique dans l'Hindou Kouch oriental (Badakhchan, Afghanistan)
Authors: Bordet Pierre , Boutiere Andre
Published: June 2020

Two tectonic units separated by the Pandjchir-Zebak fault, catazonal gneiss in recumbent folds to the north (Kokcha zones), granite to the south (Mounjan zone), petrography, Quaternary formations
Pierre Pruvost (1890-1967)
Authors: Routhier Pierre , Waterlot Gerard
Published: June 2020

French geologist, bibliography
Une zone de decrochements a l'echelle de l'Afrique dans le Precambrien de l'Ahaggar occidental
Authors: Caby Renaud
Published: June 2020

Horizontal movements contemporaneous with Panafrican tectonic episode (500