洛马贡迪-贾图利碳同位素外流的火山强迫
Janne Blichert-Toft1, Kurt Konhauser2, Baptiste Coutret2
1Laboratoire de Géologie de Lyon, CNRS UMR 5276, Ecole Normale Supérieure de Lyon, Lyon 69007, France.
概括
洛马贡迪-贾图利事件是一个主要的碳同位素外游,是由一个大型火山性省份的大规模火山二氧化碳排放驱动的. 这一事件破坏了碳循环,并可能影响了早期的真核生物进化.
科学领域:
- 地质化学 地质化学
- 古气候学 古气候学
- 地质时间学 (Geochronology)
背景情况:
- 洛马贡迪-贾图利事件 (LJE) 是地球历史上最重要的正碳同位素外游事件.
- 它的起源仍然是神秘的,发生在大氧化事件之后.
研究的目的:
- 为了确定LJE的确切年龄.
- 阐明LJE背后的因果机制及其对地球化学循环的影响.
- 探索LJE与早期真核生物进化之间的潜在联系.
主要方法:
- 来自加的法兰西维利亚FB形成的黑色页岩的Pb-Pb同步约会.
- 全球δ13C-δ18O数据集的分析.
- 火山气体排放,气候变化和碳循环的地球化学建模.
主要成果:
- 对于与LJE相关的黑页岩,确定的年龄为2,194 ± 5万年.
- LJE定时与一个主要的大火性地带 (LIP) 和orogeny之间的巧合.
- 有证据表明,火山二氧化碳排放的排气超过了性生产,导致 δ13C增加.
- 与偶发火山活动和碳酸盐和相关的 δ13C-δ18O 数据集中的双模态.
- 建议通过火山CO2对多尔效应进行调节,从而影响大气中的氧同位素.
结论:
- 与比里米 - 埃伯尼山脉形成相关的大规模火山活动是LJE的主要驱动因素.
- 偶尔的火山脱气和随后的碳循环中断解释了观察到的同位素外出.
- LJE条件可能在促进早期真核生物进化的过程中发挥了作用.
相关概念视频
Isothermal Processes
4.8K
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to maintain thermal equilibrium. Processes involving phase changes like water evaporation into steam or freezing water into ice at a constant temperature are examples of Isothermal Processes.
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
4.8K
The Fossil Record
27.0K
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...
27.0K
The Carbon Cycle
43.1K
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.
43.1K
Mass Spectrometry: Isotope Effect
3.8K
Most elements exist in nature as a mixture of isotopes. The isotopes differ in weight due to their respective number of neutrons. The molecular weight of a molecule is different depending on the specific isotope of its elements involved. As a result, the mass spectrum of the molecule exhibits peaks from the same fragment at multiple positions. The positions of these mass signals depend on the mass differences between isotopes. Furthermore, the intensity of these signals is dependent on the...
3.8K
The Sulfur Cycle
51.6K
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...
51.6K
Speciation Rates
22.5K
Overview
22.5K


