Términos relacionados

15 resultados encontrados para: TEMA: Geoquímica
  • «
  • 1 de 2
  • »
1.
- Capítulo de libro con arbitraje
*Solicítelo con su bibliotecario/a
Human influence versus natural climate variability
Torrescano Valle, Nuria (autora) ; Ramírez Barajas, Pablo Jesús (autor) ; Islebe, Gerald A. (autor) ; Vela Pelaez, Alejandro Antonio (autor) ; Folan Higgins, William J. (autor) ;
Disponible en línea
Contenido en: The holocene and anthropocene environmental history of Mexico: a paleoecological approach on Mesoamerica Cham, Switzerland : Springer International Publishing, 2019 página 171-194 ISBN:978-3-030-31718-8
Bibliotecas: Campeche , Chetumal , San Cristóbal
Cerrar
SIBE Campeche
59783-30 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
59783-20 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
59783-10 (Disponible)
Disponibles para prestamo: 1
Nota: Solicítelo con su bibliotecario/a
Resumen en español

This chapter discusses past climate change drivers and ecological responses in southeastern Mexico. Ancient human influence on ecosystems is evident from sediment cores. Past human activities are evident in fossil records but make the interpretation of the past climatic signals more difficult. Conversely the human signal provides important evidence for understanding the level of human impact on the climate system and ecosystems. Four sediment cores at different locations of the Yucatán Peninsula were analyzed for fossil pollen and geochemistry. Human-induced ecological change was evaluated compared to climate-driven environmental change. Fossil pollen gave a clear signal of landscape and precipitation change in the Preclassic and Classic periods. The geochemical ratios provided evidence of local and regional hydrological change. The Chumpich Lake registry reveals that the management of low forests was efficient and indicates good hydrological control in the landscape. However this evidence is different in other sites from Yucatán Peninsula with deficient erosion control. Probably due to the differential climate response in the Chumpich–Uxul region, the drought was not as drastic as in other places.


2.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Climate forcings on vegetation of the southeastern Yucatán Peninsula (Mexico) during the middle to late Holocene
Aragón Moreno, Alejandro Antonio ; Islebe, Gerald A. (coaut.) ; Roy, Priyadarsi D. (coaut.) ; Torrescano Valle, Nuria (coaut.) ; Mueller, Andreas D. (coaut.) ;
Contenido en: Palaeogeography, Palaeoclimatology, Palaeoecology Vol. 495 (April 2018), p. 214-226 ISSN: 0031-0182
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Climate and vegetation history from the Yucatán Peninsula, southeastern Mexico, are inferred from a mangrove sediment core deposited between the middle and late Holocene (~5600–1700 cal yr B.P.) in the Rio Hondo Delta. Fossil pollen and concentrations of Ca and Fe and Ca/Fe ratio in sediments are used to record changes in vegetation and climate. Palaeoecological and palaeoclimatic interpretations obtained from pollen abundances and associations and Fe/Ca ratio coincide with dynamics of major global forcings of climate change like ITCZ, ENSO and global cooling. Mesic conditions enabled tropical forest expansion during the middle Holocene (~5600–3650 cal yr B.P.), although there were periodic dry episodes at ~5200 cal yr B.P. and at ~4300 cal yr B.P. that caused disturbance and enabled herbaceous vegetation to expand. Changes in sedi- mentation and a gradual change from semi-evergreen to dry tropical forest occurred at ~3650 cal yr B.P., with increasing ENSO activity and southward migration of the ITCZ during transition of the middle to late Holocene. The driest period and lowest forest cover occurred between ~2600 and 2000 cal yr B.P. Data show that over the last two millennia, influence of the ENSO on southeastern Mexico is stronger compared to other proxy-records of climate variability from the Caribbean region.


3.
- Artículo con arbitraje
PDF
Resumen en: Español | Inglés |
Resumen en español

Con el fin de identificar los procesos que controlan la evolución geoquímica de las aguas subterráneas en la zona sur del estado de Quintana Roo, en los meses de octubre y noviembre de 2012 (temporada de lluvias) se muestrearon 53 pozos de abastecimiento con una profundidad promedio de 29 m. Los parámetros físicos medidos en campo fueron pH, temperatura, conductividad eléctrica y sólidos disueltos totales. Los constituyentes químicos analizados incluyeron los cationes calcio (Ca2+), magnesio (Mg2+), sodio (Na+), potasio (K+) y los aniones bicarbonato (HCO3 -), sulfato (SO4 2-), cloruro (Cl-) y nitrato (NO3 -). Estadísticos descriptivos, matrices de correlación, análisis de factores, junto con el análisis de conglomerados se utilizaron para obtener una comprensión de los procesos hidrogeoquímicos en el área de estudio. El área de estudio se caracteriza por presentar una heterogeneidad en cuanto a sus características hidrogeológicas (karst), con cambios litológicos y geológico-estructurales que dan lugar a zonas acuíferas independientes de los acuíferos de extensión regional. De acuerdo con el análisis geoquímico a través del diagrama de Piper se observaron cuatro tipos de aguas predominantes en el área de estudio: cálcica-bicarbonatada (Ca-HCO3), mixta cálcica magnésica clorurada (mixta Ca-Mg-Cl), cálcica sulfatada (Ca-SO4) y sódica clorurada (Na-Cl). A través del análisis de conglomerados se identificaron siete grupos predominantes en el área de estudio.

Dichos grupos muestran valores contrastantes en aprovechamientos cercanos, propiciados por la propia heterogeneidad del medio acuífero en donde el agua transita por diferentes rocas: calizas, dolomías y evaporitas. Se identificaron además tres factores que explican el 74.68% de la varianza observada en la composición química. Los parámetros que definen estos factores indican que los procesos hidrogeoquímicos dominantes son (1) la disolución de calizas y dolomías y el intercambio iónico; (2) la mezcla con agua marina y (3) el aporte de nutrientes por actividades humanas.

Resumen en inglés

In order to identify the processes controlling the geochemical evolution of groundwater in the southern part of the state of Quintana Roo, Mexico, 53 drinking water wells were sampled in the months of October and November 2012 (rainy season). Physical parameters measured in the field were pH, temperature, electrical conductivity and total dissolved solids. Chemical constituents analyzed include the cations calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+) and the anions bicarbonate (HCO3-), sulfate (SO42-) , chloride (Cl-) and nitrate (NO3-). Descriptive statistics, correlation matrices, factor analysis, along with cluster analysis were used to gain an understanding of the hydrogeochemical processes operating in the study area. The study area is characterized by heterogeneity in their hydrogeological characteristics (karst), with lithological and geological-structural changes that result in water-bearing zones isolated from the aquifers of regional extent. Four predominant types of water were identified in the study area: calcium-bicarbonate type (Ca-HCO3), mixed calcium-magnesium-chloride type (mixed Ca-Mg-Cl), sulfate-calcium type (Ca-SO4) and sodium-chlorided type (Na-Cl). Through cluster analysis, seven predominant groups were identified in the study area. These groups show contrasting values for nearby sites, favored by the heterogeneity of the aquifer medium where the water flows through different rocks: limestone, dolomite and evaporite. Three factors were identified through factor analysis, accounting for 74.68% of the cumulative variance. The parameters associated to these factors indicate that the dominant hydrogeochemical processes in the study area are (1) the dissolution of limestone and dolomite and ionic exchange; (2) mixing with seawater; and (3) anthropogenic nutrient input.


4.
Libro
Introduction to geochemistry: principles and applications / Kula C. Misra
Misra, Kula C. ;
Chichester, West Sussex : Wiley-Blackwell :: John Wiley and Sons, Inc. , 2012
Clasificación: 551.9 / M5
Bibliotecas: Chetumal
Cerrar
SIBE Chetumal
ECO030008485 (Disponible)
Disponibles para prestamo: 1
Índice | Resumen en: Inglés |
Resumen en inglés

Home / Earth, Space & Environmental Sciences / Geology & Geophysics / Geochemistry & Mineralogy Textbook Introduction to Geochemistry: Principles and Applications Kula C. Misra May 2012, ©2012, Wiley-Blackwell Introduction to Geochemistry: Principles and Applications (EHEP002686) cover image Read an Excerpt For Students Description This book is intended to serve as a text for an introductory course in geochemistry for undergraduate/graduate students with at least an elementary–level background in earth sciences, chemistry, and mathematics. The text, containing 83 tables and 181 figures, covers a wide variety of topics — ranging from atomic structure to chemical and isotopic equilibria to modern biogeochemical cycles — which are divided into four interrelated parts: Crystal Chemistry; Chemical Reactions (and biochemical reactions involving bacteria); Isotope Geochemistry (radiogenic and stable isotopes); and The Earth Supersystem, which includes discussions pertinent to the evolution of the solid Earth, the atmosphere, and the hydrosphere. In keeping with the modern trend in the field of geochemistry, the book emphasizes computational techniques by developing appropriate mathematical relations, solving a variety of problems to illustrate application of the mathematical relations, and leaving a set of questions at the end of each chapter to be solved by students. However, so as not to interrupt the flow of the text, involved chemical concepts and mathematical derivations are separated in the form of boxes. Supplementary materials are packaged into ten appendixes that include a standard–state (298.15 K, 1 bar) thermodynamic data table and a listing of answers to selected chapter–end questions.

Índice

Preface
1 Introduction
Part I Crystal Chemistry
2 Atomic Structure
3 Chemical Bonding
Part II Chemical Reactions
4 Basic Thermodynamic Concepts
5 Thermodynamics of Solutions
6 Geothermometry and Geobarometry
7 Reactions Involving Aqueous Solutions
8 Oxidation–Reduction Reactions
9 Kinetics of Chemical Reactions
Part III Isotope Geochemistry
10 Radiogenic Isotopes
11 Stable Isotopes
Part IV The Earth Supersystem
12 The Core–Mantle–Crust System
13 The Crust–Hydrosphere–Atmosphere System
Appendix 1 Units of measurement and physical constants
Appendix 2 Electronic configurations of elements in ground state
Appendix 3 First ionization potential, electron affinity, electronegativity (Pauling scale), and coordination numbers of selected elements
Appendix 4 Thermodynamic symbols
Appendix 5 Standard state (298.15 K, 105 Pa) thermodynamic data for selected elements, ionic species, and compounds
Appendix 6 Fugacities of H2O and CO2 in the range 0.5–10.0 kbar and 200–1000°C
Appendix 7 Equations for activity coefficients in multicomponent regular solid solutions
Appendix 8 Some commonly used computer codes for modeling of geochemical processes in aqueous solutions
Appendix 9 Solar system abundances of the elements in units of number of atoms per 106 silicon atoms
Appendix 10 Answers to selected chapter–end questions
References
Index


5.
Artículo
Aquatic ecosystems of the Yucatán Peninsula (Mexico), Belize, and Guatemala
Pérez, Liseth ; Bugja, Rita (coaut.) ; Lorenschat, Julia (coaut.) ; Brenner, Mark (coaut.) ; Curtis, Jason H. (coaut.) ; Hoelzmann, Philipp (coaut.) ; Islebe, Gerald A. (coaut.) ; Scharf, Burkhard (coaut.) ; Schwalb, Antje (coaut.) ;
Contenido en: Hydrobiologia Vol. 661, no. 1 (February 2011), p. 407-433 ISSN: 0018-8158
Resumen en: Inglés |
Resumen en inglés

This study presents limnological and morphological characteristics, physical and chemical properties of waters, and geochemistry of surface sediments for 63 aquatic ecosystems located on the karst Yucatán Peninsula and surrounding areas of Belize and the Guatemalan highlands and eastern lowlands. Our principal goal was to classify the aquatic systems based on their water variables. A principal component analysis (PCA) of the surface water chemistry data showed that a large fraction of the variance (29%) in water chemistry is explained by conductivity and major ion concentrations. The broad conductivity range, from 168 to 55,300 μS cm−1 reflects saline water intrusion affecting coastal aquatic environments, and the steep NW–S precipitation gradient, from ~450 to >3,200 mm year−1. Coastal waterbodies Celestún and Laguna Rosada displayed the highest conductivities. Minimum surface water temperatures of 21.6°C were measured in highland lakes, and warmest temperatures, up to 31.7°C, were recorded in the lowland waterbodies. Most lakes showed thermal stratification during the sampling period, with the exception of some shallow (<10 m) systems. Lakes Chichancanab, Milagros, and Bacalar displayed sulfate-rich waters. Waters of sinkholes had relatively high conductivities (<3,670 μS cm−1) and a broad range of δ18O values (−4.1 to +3.8‰).

Ca, HCO3, and SO4 dominated the waters of the lowland lakes, whereas Na was the dominant cation in highland lakes. Coastal aquatic ecosystems were dominated by Na and Cl. Cluster analysis based on surface water variables classified aquatic environments of the lowlands and highlands into three groups: (1) lowland lakes, ponds, wetlands, and coastal waterbodies (2) highland lakes, and (3) sinkholes and rivers. A broad trophic state gradient was recorded, ranging from the eutrophic Lake Amatitlán and the Timul sinkhole to oligotrophic Laguna Ayarza, with the highest water transparency (11.4 m). We used major and trace elements in surface sediments to assess pollution of waterbodies. Lakes Amatitlán, Atescatempa, El Rosario, Cayucón, Chacan-Lara, La Misteriosa, rivers Subín and Río Dulce, the wetland Jamolún, and the sinkhole Petén de Monos showed evidence of pollution and urban development. Their surface sediments displayed high concentrations of As, Cu, Fe, Ni, Pb, Se, Zn, and Zr, which suggest moderate to strong pollution.


6.
- Artículo con arbitraje
*En hemeroteca, SIBE-Chetumal
La geoquímica de Fe, Ti y Al como indicadora de la sedimentación volcanoclástica en la laguna costera de San Quintín, Baja California, México
Navarro Fernández, Eloísa (autora) ; Daesslé, L. W. (autor) ; Camacho Ibar, Victor F. (autor) ; Ortíz Hernández, Ma. Concepción (autora) ; Gutiérrez Galindo, Efraín A. (autor) ;
Disponible en línea
Clasificación: AR/551.304097223 / G4
Contenido en: Ciencias Marinas Vol. 32, no. 2 (junio 2006), p. 205-217 ISSN: 0185-3880
Bibliotecas: Chetumal , San Cristóbal
Cerrar
SIBE Chetumal
45507-10 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010017532 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Chetumal
PDF
Resumen en: Español | Inglés |
Resumen en español

Con la finalidad de identificar mediante herramientas geoquímicas la presencia de sedimento volcanoclástico producto del intempersimo y erosión de las rocas basálticas del campo volcánico de San Quintín (CVSQ), se analizaron las concentraciones de Fe, Ti y Al, así como la distribución de tamaño de grano en 32 muestras de sedimento superficial recolectado durante 2002 y 2003 en la laguna costera de San Quintín (LCSQ), Baja California. En esta zona, las rocas del CVSQ se caracterizan por tener concentraciones altas de Ti y Fe, comparadas con la corteza continental y el batolito peninsular. Lo mismo ocurre para los sedimentos de la LCSQ, los cuales tienen concentraciones de Fe (media 3.73%, desviación estándar S ± 0.99) significativamente más altas que otros sedimentos costeros reportados en Baja California y otras localidades. Las altas concentraciones de Fe normalizado (Fenorm) con respecto al porcentaje de sedimento con <63 µm en la LCSQ, indican que el enriquecimiento de Fe en algunas muestras se atribuye en parte a la presencia de minerales pesados y/o partículas líticas, relacionados con el intemperismo y erosión del CVSQ. Las altas concentraciones de Ti (media, 0.54%, S ± 0.19) en las muestras son atípicas para sedimentos costeros y marinos. Su enriquecimiento y valores altos de Ti/Al en algunas áreas de la LCSQ, especialmente en Bahía Falsa (BFa), sustentan la hipotesis de la influencia volcanoclástica.

Las muestras de sedimento que contienen la mayor proporción de oxihidróxidos de Fe amorfo (≥50% del Fe total) se localizan en BFa. Lo anterior, junto con las altas concentraciones de Fenorm, y valores elevados de Ti y Ti/Al, sugiere una asociación (al menos parcial) entre los oxihidróxidos de Fe amorfo con partículas volcanoclásticas en algunos sitios de BFa. Sin embargo, la alta variabilidad en las características geoquímicas del sedimento, sugiere una compleja interacción entre las propiedades hidrodinámicas, mineralógicas y diagenéticas en la LCSQ.

Resumen en inglés

The geochemistry of Fe, Ti and Al and the grain-size distribution were studied in 32 surficial sediment samples from San Quintín coastal lagoon (SQCL) in Baja California, in order to identify the presence of volcanoclastic sediment derived from the weathering and erosion of basaltic rocks from the San Quintín volcanic field (SQVF). The composition of the SQVF rocks is characterized by high Fe and Ti concentrations in comparison with the continental crust and Peninsular Ranges batholith. Similarly, the sediments from SQCL have significantly higher Fe concentrations (mean 3.73%, standard deviation [S] ±0.99) than other coastal sediments from Baja California and other regions. The high Fe concentrations normalized relative to the percentage of the <63-µm sediment fraction (Fenorm), indicate that the enrichment of Fe in some samples may in part be due to the presence of heavy minerals and/or rock particles, which were derived from the weathering and erosion of SQVF. The high concentrations of Ti (mean, 0.54%, S ±0.19) in the sediment are atypical for coastal and marine sediments. This enrichment as well as the high Ti/Al ratios at some sites within SQCL, especially Falsa Bay (FB), support the hypothesis of a volcanogenic influence. The sediment samples that have the highest proportion of amorphous Fe oxyhydroxides (≥50% of bulk Fe) were found in FB. This fact and the high Fenorm and Ti concentrations, as well as high Ti/Al ratios, suggest an association (at least in part) between the amorphous Fe oxyhydroxides and the volcanoclastic particles in some samples from FB; however, the high variability in geochemical characteristics of the sediment suggests a complex combination of hydrodinamic, mineralogical and diagenetic properties in SQCL.


7.
Libro
BAC: Centros de Actividades Biológica del Pacífico mexicano / D. Llunch-Belda, J. Elorduy-Garay, S. E. Lluch-Cota y G. Ponce-Díaz, editoras
Lluch Belda, Daniel (editor) ; Elorduy Garay, J. (editor) ; Lluch Cota, S. E. (editor) ; Ponce Díaz, Germán (editor) ;
Distrito Federal, México : Centro de Investigaciones Biológicas del Noroeste , c2000
Clasificación: 574.52636 / B33
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
ECO010009613 (Disponible)
Disponibles para prestamo: 1

8.
Libro
Marine geochemistry / Roy Chester
Chester, Roy (1936-) ;
Oxford : Blackwell Science , 2000
Clasificación: 551.4601 / C4
Bibliotecas: Chetumal
Cerrar
SIBE Chetumal
ECO030000818 (Disponible)
Disponibles para prestamo: 1

9.
Libro
Principles and applications of geochemistry: a comprehensive textbook for geology students / Gunter Faure
Faure, Gunter ;
New Jersey : Prentice Hall , c1998
Clasificación: 551.9 / F3
Bibliotecas: Chetumal
Cerrar
SIBE Chetumal
ECO030008397 (Disponible)
Disponibles para prestamo: 1
Índice | Resumen en: Inglés |
Resumen en inglés

Designed to show readers how to use chemical principles in solving geological problems, this book emphasizes a quantitative approach to problem solving and demonstrates how chemical principles control geologic processes in atomic and large-scale environments. The book starts with basic principles and emphasizes quantitative methods of problem-solving. It uses the principles of isotope geology to enhance the understanding of appropriate geochemical subject areas. The book also examines the geochemical processes that affect the chemical composition of surface water and that determine its quality for human consumption. For anyone interested in Geochemistry or Geology.

Índice

Preface
Part I
Planet Earth in the Solar System
1
What Is Geochemistry?
1.1 Early History
1.2 Geochemistry in the U.S.S.R.
1.3 V. M. Goldschmidt
1.4 Modern Geochemistry
References
2
In the Beginning
2.1 The Big Bang
2.2 Stellar Evolution
2.3 Nucleosynthesis
2.4 Summary
Problems
References
3
The Solar System
3.1 Origin of the Solar System
3.2 Origin of the Earthlike Planets
3.3 Satellites of the Outer Planets
3.4 Pictures of Our Solar System
3.5 Summary
References
4
Chemical Differentiation of the Earth
4.1 Internal Structure of the Earth
4.2 The Continental Crust: Major Elements
4.3 Differentiation of Igneous and Sedimentary Rocks
4.4 Differentiation of the Hydrosphere
4.5 Summary
Problems
References
Part II
Principles of Inorganic Geochemistry
5
The Electronic Structure of Atoms
5.1 The Atom of Thomson and Rutherford
5.2 Bohr’s Theory of the Hydrogen Atom
5.3 Emission of X-rays
5.4 Schrödinger’s Model of the Atom
5.5 The Aufbau Principle
5.6 Summary
Problems
References
6
The Periodic Table and Atomic Weights
6.1 Mendeleev’s Periodic Table
6.2 The Modern Periodic Table
6.3 Basic Principles of Atomic Physics
6.4 Atomic Weights
6.5 Summary
Problems
References
7
Chemical Bonds , Ionic Radii, and Crystals
7.1 Electron Donors Versus Acceptors
7.2 Measures of Metallic Character
7.3 Bonding in Molecules
7.4 Ionic Crystals
7.5 Ionic Radii
7.6 Summary
Problems
References
8
Ionic Substitution in Crystals
8.1 Goldschmidt’s Rules of Substitution
8.2 Camouflage, Capture, and Admission
8.3 Coupled Substitution: Key to the Feldspars
8.4 Distribution Coefficients and Geothermometers
8.5 Geochemical Classification of the Elements
8.6 Summary

Part III
Aqueous Geochemistry and the Stability Of Minerals
9
Acids and Bases
9.1 Chemical Reactions and Equilibria
9.2 The Law of Mass Action
9.3 Dissociation of Weak Acids and Bases
9.4 Solubility of Sparingly Soluble Bases
9.5 pH Control of Dissociation Equilibria
9.6 Solubility of Amorphous Silica
9.7 Summary Problems References
10
Salts and Their Ions
10.1 Solubility of Salts
10.2 Hydrolysis
10.3 Activities and Concentrations
10.4 Solubility of Calcium Carbonate
10.5 Chemical Weathering
10.6 Transformation of Potassium Feldspar to Kaolinite
10.7 Summary
Problems
References
11
Thermodynamics
11.1 Definitions
11.2 The First Law
11.3 Enthalpy
11.4 Heats of Reaction
11.5 Heat Capacity
11.6 The Second Law
11.7 Gibbs Free Energy
11.8 Derivation of the Law of Mass Action
11.9 Fugacity and Activity
11.10 The van’t Hoff Equation
11.11 Solubility of Amorphous Silica Between 0 and 100 °C
11.12 Summary
Problems
References
12
Mineral Stability Diagrams
12.1 Chemical Weathering of Feldspars
12.2 Formation of Zeolites
12.3 Magnesium Silicates
12.4 Solubility Diagrams
12.5 Fugacity Diagrams
12.6 Summary
Problems
References
13
Clay Minerals
Crystal Structure
Classification and Chemical Composition
Gibbs Free Energies of Formation
Stability Diagrams
Colloidal Suspensions and Ion Exchange
Dating of Clay Minerals
Summary
Problems
References
14
Oxidation-Reduction Reactions
Balancing Equations of Oxidation-Reduction Reactions
The Electromotive Series
The Emf of Electrochemical Cells
Stability Limits of Water in Terms of Eh and pH
Stability of Iron Compounds
Summary
Problems
References
15
Rates of Geochemical Processes
15.1 Rates of Chemical Reactions
15.2 Transport of Matter: Advection
15.3 Transport of Matter: Diffusion
15.4 Growth of Concretions During Diagenesis
15.5 Growth of Monomineralic Layers

15.6 Summary
Problems
References
Part IV
Isotope Geochemistry and Mixing
16
Isotopic Geochronometers
16.1 Decay Modes
16.2 Law of Radioactivity
16.3 Methods of Dating
16.4 Cosmogenic Radionuclides
16.5 Summary
Problems
References
17
Isotope Fractionation
17.1 Principles of Isotope Fractionation
17.2 Mathematical Relations
17.3 Isotope Fractionation in the Hydrosphere
17.4 Oxygen Isotope Composition of Calcite
17.5 Oxygen and Hydrogen in Clay Minerals
17.6 Groundwater and Geothermal Brines
17.7 Isotope Fractionation of Carbon
17.8 Isotope Compositions of Strontium in Carbonate Rocks
17.9 Isotope Fractionation of Sulfur
17.10 Summary
Problems
References
18
Mixing and Dilution
18.1 Binary Mixtures
18.2 Dilution
18.3 Evaporative Concentration
18.4 Ternary Mixtures
18.5 Isotopic Mixtures of One Element
18.6 Isotopic Mixtures of Two Elements
18.7 Summary
Problems
References
Part V
Applications of Geochemistry To the Solution of Global Problems
19
Consequences of Chemical Weathering
19.1 Changes in Chemical Composition of Rocks
19.2 Normative Mineral Composition of Weathering Products
19.3 Susceptibility of Minerals to Weathering
19.4 Formation of Placer Deposits
19.5 Provenance Determination by Isotopic Dating
19.6 Formation of Soils
19.7 Geomicrobiology
19.8 Food Production and Population Growth
19.9 Summary
Problems
References
20
Chemical Composition of Surface Water
20.1 Chemical Analysis of Water in Streams
20.2 Chemical Composition of Streams
20.3 Chemical Composition of Meteoric Precipitation
20.4 Normative Minerals from Water Compositions
20.5 Evaporative Concentration
20.6 Water Quality
20.7 Summary
Problems
References
21
Chemical Weathering of Mineral Deposits
21.1 Metallic Mineral Deposits
21.2 Oxidation of Iron Sulfides and the Role of Bacteria
21.3 Eh-pH Diagram for Copper Minerals

21.4 Supergene Enrichment of Fe-Cu Sulfide Deposits
21.5 Replacement of Pyrite by Chalcocite —
21.6 Oxidation of Ore Minerals of Other Metals
21.7 Geochemical Exploration
21.8 Production and Consumption of Mineral Resources
21.9 Summary
Problems
References
22
Geochemical Cycles
22.1 The Principle of Mass Balance
22.2 Mass Balance for Major Elements in the Ocean
22.3 Mass Balance for Trace Elements in the Ocean
22.4 The Cycles of C-H-O-N
22.5 The Sulfur Cycle
22.6 Summary
Problems
References
23
Chemistry of the Atmosphere
23.1 Structure and Composition
23.2 Ultraviolet Radiation
23.3 Ozone in the Stratosphere
23.4 Ozone Hole over Antarctica
23.5 Infrared Radiation and the Greenhouse Effect
23.6 Prediction of the Future Global Climate
23.7 Summary
Problems
References
24
Environmental Geochemistry: Disposal of Radioactive Waste
24.1 The Big Picture
24.2 High-Level Nuclear Waste Disposal
24.3 Geological Disposal of Radioactive Waste
24.4 Geochemistry of Plutonium
24.5 Eh-pH Diagrams of Neptunium and Plutonium
24.6 Analog Studies: The Natural Reactors at Oklo, Gabon
24.7 Reactor Accidents: Chernobyl, Ukraine
24.8 Summary
Problems
References
25
Effect of Environmental Lead on Human Health
25.1 Isotope Composition of Environmental Lead
25.2 Lead in the Environment
25.3 Lead in Plants
25.4 Lead Poisoning of Cows and Horses
25.5 Human Bones and Tissues
25.6 Lead in the Bones of Ancient Peoples
25.7 Summary
Problems
References
Appendix A
Compilations of Geochemical Data
Appendix B
Standard Gibbs Free Energies (G°f ) and Standard Enthalpies of Formation (H°f )
Author Index
Subject Index


10.
Libro
The superdeep well of the kola peninsula[Libro electrónico] / editor: Yevgeny A. Kozlovsky
Kozlovsky, Yevgeny A. (ed.) ;
New York, New York, United States : Springer-Verlag , c1987
Índice | Resumen en: Inglés |
Resumen en inglés

The present book is devoted to the study of the deep Earth's interior structure, one of the most important problems of Earth sciences today. The drilling of the Kola superdeep well inaugurated a new stage in the study of the Precambrian continental crust. The well was sunk in the northeastern part of the Baltic Shield, in an area where the Precambrian ore-bearing structures, typical of the ancient platform basements, are in juxtaposition with each other. To the present the well has been drilled to a depth of 12 km, has traversed the full thickness of the Proterozoic complex and a considerable part of the Archean stratum, and is still be­ ing worked on. This book reviews the principal results of investigations to a depth of 11,600 m; these are described in three sections: geology, geophysics, and drilling. The book begins with a general review of the history, the present state of knowledge, and trends of further investigations in the field of study of the Earth's interior and superdeep drilling. The first section of the book considers the geology of the vicinity of the Kola superdeep well and describes its geological section based on a detailed examination both of the cores and the near-borehole area.

Índice

Chapter 1. Introduction
Chapter 2. Geology
Chapter 3. Geophysics
Chapter 4. Drilling
Bibliography