Video Experimental Relacionado
Updated: Jul 11, 2026
06:55
Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
Rapida formación de la meseta de Java de Ontong por el manto Aptiano pluma de volcanismo
Science (New York, N.Y.)
|October 18, 1991
Resumen
La meseta de Ontong Java (OJP) se formó rápidamente durante el Aptiano temprano, probablemente debido a una pluma del manto. Su formación puede haber causado el aumento del nivel del mar y la anoxia oceánica, contribuyendo al clima de invernadero del Cretácico sin grandes extinciones.
Área de la Ciencia:
- Geofísica y paleoclimatología.
- Tectónica de placas y volcanismo.
Sus antecedentes:
- La meseta de Ontong Java (OJP) es una de las mayores grandes provincias ígneas de la Tierra.
- Comprender el momento y los mecanismos de su formación es crucial para comprender el clima y los eventos oceanográficos del Cretácico.
Objetivo del estudio:
- Para determinar con precisión el momento en que OJP inundó el basalto volcánico.
- Investigar las tasas de emplazamiento y el posible origen del penacho del manto de la OJP.
- Evaluar las consecuencias ambientales de la formación de OJP, incluidos los cambios en el nivel del mar, la anoxia oceánica y los impactos climáticos.
Principales métodos:
- Análisis de datos paleomagnéticos para establecer un marco de edad preciso.
- Interpretación de datos paleontológicos para la correlación estratigráfica y la datación.
- Modelado geofísico para inferir las tasas de emplazamiento de la corteza terrestre y la dinámica del penacho.
Principales resultados:
- La mayoría de la formación de OJP ocurrió rápidamente, en un lapso de 3 millones de años, durante el Aptiano temprano.
- Las tasas de emplazamiento de la corteza eran significativamente más altas que las de las trampas del Decán.
- La rápida formación es consistente con el impacto de una gran cabeza de penacho del manto en la base de la litosfera oceánica.
Conclusiones:
- La formación de OJP fue un evento rápido impulsado por la actividad de la pluma del manto.
- El volcanismo de OJP probablemente desencadenó un aumento global del nivel del mar e indujo una anoxia oceánica generalizada.
- Si bien contribuyó al clima de efecto invernadero del Cretácico medio, la formación de OJP no causó grandes extinciones biológicas.
Videos de Conceptos Relacionados
02:33Phase Transitions: Sublimation and Deposition
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
02:34Arrhenius Plots
The Arrhenius equation relates the activation energy and the rate constant, k, for chemical reactions. In the Arrhenius equation, k = Ae−Ea/RT, R is the ideal gas constant, which has a value of 8.314 J/mol·K, T is the temperature on the kelvin scale, Ea is the activation energy in J/mole, e is the constant 2.7183, and A is a constant called the frequency factor, which is related to the frequency of collisions and the orientation of the reacting molecules.
The Arrhenius equation can be used to...
The Arrhenius equation can be used to...
01:21Isothermal Processes
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...
01:10Volatilization
Volatilization gravimetry is an analytical technique that measures the mass lost due to the volatilization of the substance. This technique is used to estimate the amount of volatile material in a sample. To perform this method, heat a known amount of the sample to a high temperature in a crucible or other suitable vessel. The volatile substance in the sample evaporates, and the vapor is completely expelled from the crucible either by heating the sample or bubbling a stream of inert gas through...
01:23Propagation of Action Potentials
The propagation of an action potential refers to the process by which a nerve impulse, or "action potential," travels along a neuron.
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
01:22Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...