Video Experimental Relacionado
Updated: Jul 10, 2026
06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Determinar la composición de la Tierra
Michael J Drake1, Kevin Righter
1Lunar and Planetary Laboratory, University of Arizona, Tucson 85721-0092, USA. drake@lpl.arizona.edu
Nature
|March 8, 2002
Resumen
Los bloques de construcción de la Tierra no se encuentran en las colecciones actuales de meteoritos. Un nuevo análisis sugiere que la Tierra se formó a partir de materiales únicos, sin muestras, denominados "condritas terrestres" o "acondritas terrestres".
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La geoquímica es la geoquímica.
- Cosmoquímica es la cosmoquímica.
Sus antecedentes:
- La composición de la Tierra y los planetas terrestres es una cuestión fundamental en la ciencia planetaria.
- Históricamente, los meteoritos condríticos fueron considerados los bloques de construcción primarios de los planetas terrestres.
- Las colecciones de meteoritos existentes no representan completamente la composición material del manto de la Tierra.
Objetivo del estudio:
- Para investigar el origen de los bloques de construcción de la Tierra.
- Para conciliar las composiciones químicas e isotópicas de la Tierra, Marte, cometas y meteoritos.
- Para identificar los componentes que faltan en las colecciones actuales de meteoritos.
Principales métodos:
- Análisis comparativo de las relaciones Mg/Si y Al/Si.
- Análisis de las relaciones isótopo-oxígeno, isótopo-osmio, D/H, Ar/H2O y Kr/Xe.
- Comparación de las composiciones de materiales terrestres y extraterrestres.
Principales resultados:
- Existen discrepancias significativas entre la composición material de la Tierra y la de los meteoritos conocidos.
- Las relaciones isotópicas y elementales (Mg/Si, Al/Si, O, Os, H, Ar, Kr) indican precursores únicos para la Tierra y Marte.
- Actualmente no se encuentra ningún material primitivo que coincida con la composición del manto de la Tierra en las colecciones de meteoritos.
Conclusiones:
- Los 'bloques de construcción' de la Tierra no están representados por los meteoritos condríticos actualmente disponibles.
- La Tierra probablemente se formó a partir de materiales primitivos no muestreados, conocidos como "condritas terrestres" o "acondritas terrestres".
- La investigación futura debe centrarse en la identificación y caracterización de estos precursores terrestres únicos.
Más Videos Relacionados
11:50Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
08:38Combined Size and Density Fractionation of Soils for Investigations of Organo-Mineral Interactions
Published on: February 15, 2019
Videos de Conceptos Relacionados
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
02:23The Soil Ecosystem
Plants obtain inorganic minerals and water from the soil, which acts as a natural medium for land plants. The composition and quality of soil depend not only on the chemical constituents but also on the presence of living organisms. In general, soils contain three major components:
03:35Classifying Matter by Composition
Matter: Pure Substances and Mixtures
According to its composition, the matter can be classified into two broad categories — pure substances and mixtures.
A pure substance is a form of matter that has a constant composition throughout with uniform properties. For example, any sample of sucrose has the same composition and same physical properties, such as melting point, color, and sweetness, regardless of the source from which it is isolated.
A mixture is composed of two or more types of...
According to its composition, the matter can be classified into two broad categories — pure substances and mixtures.
A pure substance is a form of matter that has a constant composition throughout with uniform properties. For example, any sample of sucrose has the same composition and same physical properties, such as melting point, color, and sweetness, regardless of the source from which it is isolated.
A mixture is composed of two or more types of...
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
01:13What is Matter?
The substance of the universe—from a grain of sand to a star—is called matter. Scientists define matter as anything that occupies space and has mass. An object’s mass and its weight are related concepts, but not quite the same. An object’s mass is the amount of matter contained in the object and is the same whether that object is on Earth or in the zero-gravity environment of outer space. An object’s weight, on the other hand, is its mass as affected by the pull of gravity. Where gravity...
01:28Geoid and Ellipsoid
The Earth's shape is best described as an ellipsoid, a slightly flattened sphere created by rotating an ellipse around its minor axis. This flattening results in the polar axis being about 21 kilometers shorter than the equatorial axis. In contrast, the geoid represents the Earth's gravitational shape and aligns with the mean sea level (MSL). The geoid is an irregular equipotential surface where gravity is perpendicular at every point. Variations in Earth's mass distribution cause geoid...