Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.

Aggregation of the yeast Kluyveromyces bulgaricus is mediated by the galactose-specific lectin KbCWL1. This lectin contains hydrophobic amino acids and its activity is calcium dependent. A specific fluorescent probe, 1-anilinonaphthalene-8-sulfonic acid in the free acid form (ANS; Sigma Chemical Co., St. Louis, Missouri), was used to study the hydrophobic areas on the cellular surface of K. bulgaricus. Changes in surface hydrophobicity during the growth and aggregation of yeast cells were studied. Surface hydrophobicity increased during growth and depended on the amount of yeast cells in the culture medium. During growth, the size of the hydrophobic areas on the cell surface was measured using ANS and was found to increase with the percentage of flocculating yeasts. Our results strongly suggest that the hydrophobic areas of the cell walls of yeast cells are involved in the aggregation of K. bulgaricus.

The lectin-like theory suggest that yeast flocculation is mediated by an aggregating lectinic factor. In this study we isolated an agglutinating factor, which corresponds to lectin, from whole cells by treating the flocculent wild-type Saccharomyces cerevisiae NCYC 625 strain and its weakly flocculent mutant [rho degrees ] with EDTA and two non-ionic surfactants (Hecameg and HTAC). The dialysed crude extracts obtained in this way agglutinated erythrocytes and this hemagglutination was specifically inhibited by mannose and mannose derivatives. However, SDS-PAGE profiles showed that the three reagents had different effects on the yeast cells. The non-ionic surfactants appeared to be the most efficient, as their extracts possessed the highest specific agglutinating activity. The products released by the wild-type strain presented a higher specific agglutinating activity than those released by the [rho degrees ] mutant. Purification of the agglutinating factor from extracts of both strains by affinity chromatography revealed two active bands of relative mass of 26 and 47 kDa on SDS-PAGE. Mass spectrometry analysis by MALDI-TOF, identified a 26 kDa band as the triose phosphate isomerase (TPI) whereas a 47 kDa band was identical to enolase. Edman degradation showed that the N-terminal sequences of these proteins were similar to TPI and enolase, respectively. The difference in the flocculation behaviour of the two strains is due to changes in the protein composition of the cell wall and in the protein structure involved in cell-cell recognition.

The work reported herein deals with the study of cellular recognition and permeability phenomena in yeasts. Various galactosylated organic telomers derived from trishydroxymethyl-aminomethane (THAM) and bearing fluorescent moieties were synthesized in order to measure their ability to cross the yeast cell envelope. Grafting fluorescent probes on the organic telomer backbone allowed us to study their specific behaviors toward the yeasts by fluorescence microscopy. Yeasts belonging to the genera Kluyveromyces and Saccharomyces were used for this study. With Saccharomyces yeast cells bearing mannose-specific lectins or lectin-like proteins, on their outer surface, all the galactosylated or nongalactosylated organic telomers passed through the cell envelope and invaded the cytoplasm. With Kluyveromyces yeast cells bearing galactose-specific lectins, the galactosylated organic telomers were blocked at the outer surface while the nongalactosylated derivatives crossed the cell envelope. Moreover, preincubation of Kluyveromyces yeasts with galactose or methylgalactose inhibited the cell surface anchorage of the organic telomers and allowed their penetration into the cytoplasm. When assays were performed on spheroplasts of both Kluyveromyces and Saccharomyces yeasts, no fixation on the surface could be observed, and all the derivatives went through the membrane and invaded the cytoplasm.

The clay mineral assemblages of the Cretaceous-Tertiary (K/T) transition recorded in southern Peten sedimentary rocks have been studied in sections dated by calcareous nannofossils and foraminifera. The deposits contain cosmic and impact remains (iridium, Ni-rich magnetite, tektite) and typical Cheto smectites resulting from weathered tektites (glass spherules) produced by the Yucatan impact. The clay mineral assemblages are used for describing the palaeoenvironmental and tectonic evolution of southern Peten near the K/T boundary.

The clay mineral assemblages of the Cretaceous-Tertiary (K/T) transition recorded in southern Peten sedimentary rocks have been studied in sections dated by calcareous nannofossils and foraminifera. The deposits contain cosmic and impact remains (iridium,Ni-rich magnetite, tektite) and typical Cheto smectites resulting from weathered tektites (glass spherules) produced by the Yucatan impact. The clay mineral assemblages are used for describing the palaeoenvironmental and tectonic evolution of southern Peten near the K/T boundary.

Numerical data of clay mineral analyses of Upper Jurassic to Cretaceous formations from both Maya and Chortis blocks, located north and south of Guatemala respectively, were replaced in the presently-known palaeogeographic, stratigraphic and lithologic framework, which allowed to distinguish the respective influence of geodynamic and diagenetic constraints. The identified diagenetic effects are frequently recognized and resulted from depth of burial, tectonic features and ophiolite emplacement. Such effects nevertheless obliterate partly only the geodynamic messages expressed by clay mineral associations on the detrital sources, on weathering and drainage conditions controlled by warm humid climate, on the occurrence of seaways between the different sedimentary basins, and on tectonic events. The diagenetic effects appear to predominate in the southeastern Guatemala and to the south of the fault system separating the Maya and the Chortis blocks. The palaeogeographic conditions seem to have especially varied to the west of the northern Maya block during late Mesozoic times.

Petrological and geochemical studies on Othrys lavas from the Maliac zone (internal zones) and on Vardoussia lavas from the eastern border of the Pindos-Olonos zone (external zones) show evidence for two distinct Triassic volcanism suites in the Hellenides. Othrys lavas are of anorogenic type. They present typical features of the more or less enriched MORB type tholeiitic suites. On the other hand Vardoussia lavas belong to an orogenic calc-alkaline suite. Consequently, most of the geodynamic models explaining the Triassic Hellenic volcanism only with subduction zones need to be modified. The models have to take into account the anorogenic character of some of the lavas (e.g.: in the Maliac zone of Othrys).

Petrological and geochemical studies on Othrys lavas from the Maliac zone (internal zones) and on Vardoussia lavas from the eastern border of the Pindos-Olonos zone (external zones) show evidence for two distinct Triassic volcanism suites in the Hellenides. Othrys lavas are of anorogenic type. They present typical features of the more or less enriched MORB type tholeiitic suites. On the other hand Vardoussia lavas belong to an orogenic calc-alkaline suite. Consequently, most of the geodynamic models explaining the Triassic Hellenic volcanism only with subduction zones need to be modified. The models have to take into account the onorogenic character of some of the lavas (e. g,: in the Maliac zone of Othrys)

The Beotian zone borders the internal Hellenic zones in the west and is limited in the west by the Parnasse or the Pindos-Olonos zone. The clay fractions of the Beotian Radiolarites (Middle to Upper Jurassic) and of the pelitic Flysch (Upper Tithonian-Berriasian) show very weak diagenesis. The Beotian Radiolarites exhibit trivial clay mineral assemblages which are similar to those of the Pindos Radiolarites. At the Beotian - Radiolarites - Flysch boundary, a significant change in the clay assemblages occurs, reflecting changes in source areas. The abundance of trioctahedral smectite (saponite) in the Beotian Flysch clay fractions, their high Fe/Ti ratio and their relatively high chromium and nickel content are indicative of a detrital origin from the reworking of alterites covering ultrabasic rocks. The clay assemblage of the Beotian Radiolarites and Flysch can be used as tracers to thrusting the ophiolites onto the Pelagonian zone during the late Jurassic. In the Pindos-Olonos series, the Radiolarites-Calpionellid Limestone boundary is dated from the late Tithonian and shows the same change in clay mineralogical and geochemical parameters. The large areal extension of the mentioned tracers contributes to the reconstruction of ophiolite obduction in the Hellenids in late Jurassic and early Cretaceous times.

East of the Parnassus range, within the Beotian Flysch, the < 2-mu-m fractions of clays or marls are characterized by the occurrence of magnesian clay minerals which marks ophiolite obduction upon the Pelagonian zone. Some are classical (saponite +/- serpentine +/- talc), others are less common (aliettite). Within some samples, we notice the transformation of saponite to corrensite. This transformation is not total and corresponds to the beginning of the saponite to chlorite transition. The observed high values of vitrinite reflectance (0.89 to 1.10) suggest that mineral reactions would be lagging behind coalification. This lag between organic and mineral diagnesis can be explained by the briefness of the period of heating.

Other| May 01, 1990 Sedimentologie, mineralogie des argiles et chimie des sediment miocenes a quaternaires du site 645 (Leg ODP-105-baie de Baffin); origines et implications climatiques et courantologiques F. Thiebault; F. Thiebault Author Univ. Lille-Flandres-Artois, Sci. Terre, Lab. Dynam. Sediment. Struct., Villeneune d'Ascq 59655, France Search for other works by this author on: GSW Google Scholar M. Cremer M. Cremer Author Search for other works by this author on: GSW Google Scholar Author and Article Information F. Thiebault Author Univ. Lille-Flandres-Artois, Sci. Terre, Lab. Dynam. Sediment. Struct., Villeneune d'Ascq 59655, France M. Cremer Author Publisher: Société Géologique de France First Online: 03 Mar 2017 Online ISSN: 1777-5817 Print ISSN: 0037-9409 GeoRef, Copyright 2012, American Geosciences Institute. Reference includes data from PASCAL, Institute de l'Information Scientifique et Technique, Vandoeuvre-les-Nancy, France Bulletin de la Société Géologique de France (1990) VI (3): 457–468. https://doi.org/10.2113/gssgfbull.VI.3.457 Article history First Online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation F. Thiebault, M. Cremer; Sedimentologie, mineralogie des argiles et chimie des sediment miocenes a quaternaires du site 645 (Leg ODP-105-baie de Baffin); origines et implications climatiques et courantologiques. Bulletin de la Société Géologique de France 1990;; VI (3): 457–468. doi: https://doi.org/10.2113/gssgfbull.VI.3.457 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin de la Société Géologique de France Search Advanced Search This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Subcontinuously cored early(?)-middleMiocene to recently deposited sediments from ODP Site 645 were studied texturally, mineralogically, and geochemically.The entire sequence contains minerals and associated chemical elements that are chiefly of detrital origin.In particular, the clay minerals, which include smectite, kaolinite, chlorite, and illite, are detrital.No obvious evidence of diagenesis with depth, of burial, of volcanism, or of hydrothermal alteration was observed.The sedimentary textures, clay mineralogy, and <2-/«n fraction geochemistry of the early middle Miocene sediments (630 to 1147 mbsf) suggest the pronounced but variable influence of a southward bottom current.Two clay facies are defined.The lower one, Cj (780 to 1147 mbsf), is characterized by the great abundance of discrete smectite (with less than 15% illite interlayers), probably detrital in origin, and reworked older, discrete, smectite-rich sediments.The upper clay facies, C 2 (630 to 780 mbsf), shows a net decrease of the fully expandable clay abundances, with a great abundance of mixed-layer, illite-smectite clays (60 to 80% of illite interlayers).Such clay assemblages can be inherited from paleosoils or older sedimentary rocks.An important change occurs at 630 mbsf (clay fraction) or 600 mbsf (sedimentary texture), which may be explained by the beginning of continental glaciation (630 mbsf, ~ 9 Ma) and the onset of ice rafting in Baffin Bay (600 mbsf, ~ 8 Ma).Above this level, the characteristics and modifications of the clay assemblages are controlled climatically and can be explained by the fluctuations of (1) ice-rafting, (2) speed of weak bottom currents, and (3) some supply by mud turbiditic currents.Three clay facies (C 3 , C 4 , and C 5 ) can be defined by the abrupt increases of the inherited chlorite and illite clays.

Claystones immediately overlying the early Eocene age ocean-floor basalt, cored at Ocean Drilling Program (ODP) Site 647, underwent hydrothermal and thermal alterations originating from the basalt, which resulted in changes in both the mineralogical and chemical composition of the sediments. Chlorites and higher magnesium and iron concen­ trations were found in the lowermost sediment sequence. Upcore, changes in the bulk chemical composition of the sedi­ ments become smaller, when compensated for variations in the carbonate content originating from biogenic and authi­ genic components. Chlorite disappears upcore, but still only part of the swelling clay minerals have survived the thermal influence. Thirty meters above the basalt, the clay mineralogy and chemical composition become uniform throughout the Paleogene section. Iron-rich smectites (i.e., nontronitic types), totally dominate the clay mineral assemblage. Bio­ genic components, responsible for the dominant part of the calcite and cristobalite contents, vary in amount in the up­ per part, and so do the authigenic carbonate and sulfide contents. Detrital components, such as kaolinite, illite, quartz, and feldspars, make up a very small proportion of the sediment record. The nontronitic smectites are believed to be au­ thigenic, formed by a supply of iron from the continuous formation of ocean-floor basalt in the ridge area that reacted with the detrital and biogenic silicates and alumina silicates.

Claystones immediately overlying the early Eocene age ocean-floor basalt, cored at Ocean Drilling Program (ODP) Site 647, underwent hydrothermal and thermal alterations originating from the basalt, which resulted in changes in both the mineralogical and chemical composition of the sediments.Chlorites and higher magnesium and iron concentrations were found in the lowermost sediment sequence.Upcore, changes in the bulk chemical composition of the sediments become smaller, when compensated for variations in the carbonate content originating from biogenic and authigenic components.Chlorite disappears upcore, but still only part of the swelling clay minerals have survived the thermal influence.Thirty meters above the basalt, the clay mineralogy and chemical composition become uniform throughout the Paleogene section.Iron-rich smectites (i.e., nontronitic types), totally dominate the clay mineral assemblage.Biogenic components, responsible for the dominant part of the calcite and cristobalite contents, vary in amount in the upper part, and so do the authigenic carbonate and sulfide contents.Detrital components, such as kaolinite, illite, quartz, and feldspars, make up a very small proportion of the sediment record.The nontronitic smectites are believed to be authigenic, formed by a supply of iron from the continuous formation of ocean-floor basalt in the ridge area that reacted with the detrital and biogenic silicates and alumina silicates.