Video Experimental Relacionado
Updated: Dec 9, 2025
10:18
Dynamic Pore-scale Reservoir-condition Imaging of Reaction in Carbonates Using Synchrotron Fast Tomography
Published on: February 21, 2017
8.8K
El ciclo de carbono de la litosfera al manto inferior registrado en diamantes superprofundos
M E Regier1, D G Pearson2, T Stachel2
1Canadian Centre for Isotopic Microanalysis, Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada. margoregier@gmail.com.
Nature
|September 10, 2020
Resumen
La corteza oceánica carbonatada, no el sedimento, es la principal fuente de carbono de la tierra profunda. Las inclusiones de diamantes revelan que este carbono se subduce a la zona de transición, formando diamantes y una barrera de carbono del manto inferior.
Área de la Ciencia:
- Geoquímica
- Minerología
- Geología
Sus antecedentes:
- El transporte de carbono en el manto de la Tierra es crucial para el ciclo del carbono, influyendo en el clima y los estados redox.
- Existe incertidumbre con respecto a la profundidad de subducción de los depósitos de carbono (sedimentos, corteza oceánica) y su contribución al secuestro de carbono en el manto profundo.
- Los diamantes sublitosféricos (desde más de 250 km de profundidad) proporcionan información sobre los procesos profundos de la Tierra y el transporte de carbono.
Objetivo del estudio:
- Investigar el origen y las vías de subducción de los depósitos de carbono en el manto de la Tierra.
- Para determinar si los sedimentos o la corteza oceánica alterada son los principales portadores de carbono durante la subducción.
- Para limitar las profundidades de subducción de carbono y su papel en el secuestro de carbono profundo del manto.
Principales métodos:
- Las mediciones de isótopos de oxígeno de las inclusiones minerales dentro de los diamantes superprofundos (litosfera al manto inferior).
- Análisis del contenido de isótopos de carbono y nitrógeno de los diamantes anfitriones.
- Comparación de las firmas isotópicas entre las inclusiones de diamantes sublitosféricas y litosféricas.
Principales resultados:
- La corteza oceánica ígnea carbonatada, no el sedimento, es el reservorio de carbono dominante para losas subducidas a las profundidades de la zona de transición (<660 km).
- Las inclusiones sublitosféricas muestran enriquecimiento en 18O, lo que indica la cristalización de los fundidos de la corteza oceánica subducida rica en carbonato.
- Las inclusiones del manto inferior (> 660 km) exhiben valores isotópicos típicos del manto inalterado, lo que sugiere movilización de carbono y formación de diamantes sin perturbación isotópica.
Conclusiones:
- La corteza oceánica subducida es la principal fuente de carbono secuestrado en la zona de transición.
- Una transición de la fusión de la losa de carbonato (zona de transición) a la deshidratación de la losa (manto inferior) crea una barrera para la subducción profunda de carbono.
- El carbono se moviliza y se concentra en el manto inferior para formar diamantes, sin alterar las firmas isotópicas del manto ambiental.
Videos de Conceptos Relacionados
01:14The Carbon Cycle
42.7K
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
42.7K
02:56The Fossil Record
26.8K
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
26.8K
01:22The Sulfur Cycle
51.4K
Sulfur, an important element in the chemical makeup of proteins, is recycled through the atmosphere and aquatic and terrestrial environments. Found in the atmosphere as sulfur dioxide (SO2), sulfur is released by decaying organisms, weathered rocks, geothermal vents, volcanos, and burning fossil fuels. It is deposited into the ecosystem, cycled through the biotic community, and either released back into the atmosphere as gas or deposited in marine sediment for long-term storage and eventual...
51.4K
01:04¹³C NMR: ¹H–¹³C Decoupling
1.5K
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
1.5K
00:54What are Biogeochemical Cycles?
38.8K
The most common elements in organic molecules, carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, are only available in the ecosystem in limited amounts. Therefore, these nutrients must be recycled through both biotic and abiotic components of the ecosystem, in processes generally called biogeochemical cycles.
38.8K
01:21The Phosphorus Cycle
43.2K
Unlike carbon, water, and nitrogen, phosphorus is not present in the atmosphere as a gas. Instead, most phosphorus in the ecosystem exists as compounds, such as phosphate ions (PO43-), found in soil, water, sediment and rocks. Phosphorus is often a limiting nutrient (i.e., in short supply). Consequently, phosphorus is added to most agricultural fertilizers, which can cause environmental problems related to runoff in aquatic ecosystems.
43.2K