Video Experimental Relacionado
Updated: Jul 15, 2026
07:57
Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis
Published on: August 15, 2018
La evidencia isotópica de carbono para la inestabilidad del hidrato de metano durante los interestadios cuaternarios
1Geological Sciences and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA. Department of Geological Sciences, California State University, Long Beach, CA 90840, USA.
Science (New York, N.Y.)
|February 7, 2001
Resumen
La disociación del hidrato de metano en los sedimentos marinos causó grandes desplazamientos isotópicos de carbono durante 60.000 años. Estos eventos, vinculados a los cambios climáticos, liberaron metano, lo que afectó la composición atmosférica.
Área de la Ciencia:
- La paleoceanografía es la paleoceanografía.
- La geoquímica marina es la geoquímica marina.
- Ciencias del clima ciencia del clima.
Sus antecedentes:
- Oscilaciones isotópicas del carbono a escala milenaria observadas en foraminíferos bentónicos de la cuenca de Santa Bárbara.
- Estas oscilaciones sugieren cambios en los gradientes de metano sedimentario y la disociación de hidrato de gas en los últimos 60.000 años.
Objetivo del estudio:
- Para investigar las causas de las oscilaciones isotópicas de carbono a escala milenaria en la cuenca de Santa Bárbara.
- Comprender el papel de la disociación del hidrato de gas en estas oscilaciones y su impacto potencial en el metano atmosférico.
Principales métodos:
- Análisis de los isótopos de carbono bentónicos y planctónicos de los foraminiferos durante los últimos 60.000 años.
- Correlación de los datos isotópicos con las proxies paleoceanográficas y los registros climáticos.
Principales resultados:
- Las grandes oscilaciones isotópicas del carbono a escala milenaria (aprox. 5 por mil) reflejan la desgasificación de metano de la disociación del hidrato de gas durante las interestadias.
- Las excursiones breves y negativas (hasta -6 por mil) indican liberaciones masivas de metano de los sedimentos de la cuenca.
- La estabilidad del hidrato de gas fue influenciada por los cambios de temperatura del agua intermedia relacionados con los cambios de circulación termohalina.
Conclusiones:
- La disociación del hidrato de metano y la posterior liberación de metano impactaron significativamente los ciclos de carbono a escala milenaria.
- Estos procesos probablemente contribuyeron a las amplias oscilaciones del metano atmosférico a lo largo del margen de California y potencialmente a nivel mundial.
- La circulación termohalina jugó un papel clave en la modulación de la estabilidad del hidrato de gas.
Más Videos Relacionados
11:38In situ FTIR Spectroscopy as a Tool for Investigation of Gas/Solid Interaction: Water-Enhanced CO2 Adsorption in UiO-66 Metal-Organic Framework
Published on: February 1, 2020
07:32Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.
Published on: June 4, 2021
Videos de Conceptos Relacionados
01:12Carbon Skeletons
Life on Earth is carbon-based, as all macromolecules that make up living organisms contain carbon atoms. All organic compounds have a carbon backbone. Each carbon atom is tetravalent and can bond with four other atoms, making it an extraordinarily flexible component of biological molecules. Because carbon’s valence electrons are stable, it rarely becomes an ion. As the carbon chain increases in length, structural modifications such as ring structures, double bonds, and branching side chains...
02:39Phase Diagrams
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
01:59Relative Stabilities of Alkenes
The relative stability of alkenes can be determined by comparing their heats of hydrogenation. The lower heat of hydrogenation indicates the more stable alkene. The three main factors determining the relative stability of alkenes are i) the number of substituents attached to the double-bond carbon atoms, ii) hyperconjugation, and iii) the stereochemistry of the double bond.
01:23Stability of Equilibrium Configuration
Understanding the stability of equilibrium configurations is a fundamental part of mechanical engineering. In any system, there are three distinct types of equilibrium: stable, neutral, and unstable.
A stable equilibrium occurs when a system tends to return to its original position when given a small displacement, and the potential energy is at its minimum. An example of a stable equilibrium is when a cantilever beam is fixed at one end and a weight is attached to the other end. If the weight...
A stable equilibrium occurs when a system tends to return to its original position when given a small displacement, and the potential energy is at its minimum. An example of a stable equilibrium is when a cantilever beam is fixed at one end and a weight is attached to the other end. If the weight...
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
01:24Carbonation Shrinkage
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...