Related Experiment Video
Updated: May 4, 2026
08:18
Design and Use of a Full Flow Sampling System FFS for the Quantification of Methane Emissions
Published on: June 12, 2016
17.4K
Methane and carbon at equilibrium in source rocks
1Petroleum Habitats, 806 Soboda, Houston, TX 77079, USA. dinacat.mango@gmail.com.
Geochemical Transactions
|December 17, 2013
Summary
Methane in shale may exist in equilibrium with solid carbon and higher hydrocarbons, not just as free gas. This suggests source rocks could hold significantly more gas than currently estimated.
Area of Science:
- Geochemistry
- Petroleum Geology
- Chemical Thermodynamics
Background:
- Methane is a primary component of natural gas found in source rocks.
- The state of methane (free gas vs. adsorbed/in equilibrium) influences reservoir potential.
Purpose of the Study:
- To investigate the hypothesis that methane in source rocks exists in equilibrium with carbon and higher hydrocarbons.
- To provide evidence for a gas-solid equilibrium model in shale formations.
Main Methods:
- Analysis of gas ingestion and selectivity in shales (Fayetteville and Mowry) under varying conditions.
- Evaluation of production decline curves from a Fayetteville Shale well.
- Development and application of a new general gas-solid equilibrium model for natural gas and hydrocarbons.
Main Results:
- Shales demonstrate gas ingestion patterns consistent with gas-carbon equilibrium, with a 50% increase in solid hydrocarbon mass observed.
- Mowry Shale selectively ingests butane from argon but not from methane.
- Production data aligns with theoretical gas withdrawal from higher hydrocarbons in equilibrium with carbon.
- The gas-solid equilibrium model supports methane existing in equilibrium with carbon and higher hydrocarbons.
Conclusions:
- Evidence strongly supports methane existing in equilibrium with carbon and higher hydrocarbons within source rocks.
- Higher hydrocarbons in source rocks may function as gas reservoirs.
- Shale gas deposits could contain substantially more gas than currently recognized.
Related Concept Videos
01:26Microbes and Methanogenesis
91
Methanogenesis is a critical microbial process in anaerobic ecosystems responsible for the biological production of methane, a potent greenhouse gas and valuable biofuel. This metabolic pathway is primarily facilitated by methanogenic archaea, which thrive in anoxic environments such as wetlands, sediments, and animal gastrointestinal tracts. The absence of oxygen in these habitats prevents aerobic respiration, thereby favoring alternative biochemical pathways for organic matter degradation.In...
91
01:27Microbes and Climate Change
91
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...
91
01:23Mass Spectrum
5.3K
A mass spectrum is the graphical representation of the relative abundance of the charged fragments in an analyte plotted against their mass-to-charge ratio (m/z). The plot's x-axis represents the ratio of the mass of the charged fragment to the number of charges it carries. The y axis of the plot represents the relative abundance of each charged species. The relative abundance is calculated from the signal intensity of each charged species recorded at the detector. The most intense signal (the...
5.3K
02:55Thermochemical Equations
29.5K
For a chemical reaction (the system) carried out at constant pressure – with the only work done caused by expansion or contraction – the enthalpy of reaction (also called the heat of reaction, ΔHrxn) is equal to the heat exchanged with the surroundings (qp).
29.5K
01:14The Carbon Cycle
32.8K
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.
32.8K
01:25Microbial Interactions: Mutualism
80
Mutualism is a symbiotic interaction in which all participating organisms benefit. These relationships can be obligate or facultative and are fundamental to ecosystem functions across diverse biological systems.Plant–Fungi MutualismOne well-known example is the association between plant roots and mycorrhizal fungi, such as Rhizophagus species. The fungal hyphae penetrate the root hairs and the epidermis, forming an extensive hyphal network that establishes a symbiotic association. Through...
80