What is methane and why is it a safety concern?

Methane (a gas composed of carbon and hydrogen) is produced two ways:

  • Through biologic decomposition of organic matter at shallow depths. Swamps, landfills, and even shallow bedrock are some settings where this occurs. 
  • Methane can also be derived over millions of years by high pressure and high temperature processes that produce fossil fuels deep underground. Examples include coal deposits and oil and natural gas accumulations.

Under the right conditions, methane gas can migrate into water wells along with the groundwater. High concentrations of methane in water wells can accumulate in confined spaces and act as an asphyxiant or become flammable. These dangers can be mitigated through enhanced venting of the well casing or venting confined spaces (like basements) and removing any ignition sources.


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What are gas hydrates?

Gas hydrates are a crystalline solid formed of water and gas. It looks and acts much like ice, but it contains huge amounts of methane; it is known to occur on every continent; and it exists in huge quantities in marine sediments in a layer several hundred meters thick directly below the sea floor and in association with permafrost in the Arctic...

Why are some lakes full of algae and thick plants?

Plants naturally grow in and around lakes, but sometimes lakes and ponds can get an overgrowth of plants, algae, or bacteria. In many cases, humans are responsible. Chemicals that are used on lawns and in agriculture (like nitrogen and potassium) wash into our water systems. Once there, plants and algae have a feast on this “food”. Sometimes...

How does mine drainage occur?

Mine drainage is formed when pyrite (an iron sulfide) is exposed and reacts with air and water to form sulfuric acid and dissolved iron. Some or all of this iron can precipitate to form the red, orange, or yellow sediments in the bottom of streams containing mine drainage. The acid runoff further dissolves heavy metals such as copper, lead, and...
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Date published: January 4, 2017

Exploring Gas Hydrates as a Future Energy Source

In the past decade, the development of the Barnett, Eagle Ford, Marcellus, and other shales has dominated the national consciousness regarding natural gas. But in Alaska, another form of natural gas has been the focus of research for decades—methane hydrate.

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Date published: March 6, 2017

USGS Finds Elevated Levels of Arsenic, Radon, Methane in Some Private Wells in Lycoming County, Pennsylvania

Tests of 75 private drinking water wells in Lycoming County, in north-central Pennsylvania, found water from most of the sampled wells contained concentrations of radon that exceeded a proposed, nonbinding health standard for drinking water. Smaller percentages of the wells contained concentrations of arsenic or methane that exceed existing drinking water standards.

Date published: June 16, 2016

Atlantic Methane Seeps Surprise Scientists

Recent scientific work has confirmed the source, composition and origin of methane seeps on the Atlantic Ocean seafloor, discovered in 2012, where scientists never expected them to be.

Date published: April 11, 2016

Methane from Some Wetlands May Lower Benefits of Carbon Sequestration

Methane emissions from restored wetlands may offset the benefits of carbon sequestration a new study from the U.S. Geological Survey suggests. 

Date published: August 25, 2014

Natural Methane Seepage on U.S. Atlantic Ocean Margin Widespread

Natural methane leakage from the seafloor is far more widespread on the U.S. Atlantic margin than previously thought, according to a study by researchers from Mississippi State University, the U.S. Geological Survey, and other institutions.

Date published: February 25, 2014

Changes in Stream-Water Quality Attributed to Coalbed Methane Development

Three sites on the Powder River show a difference in water quality between the time prior to coalbed methane development and during the production period, according to a new U.S. Geological Survey report.

Date published: December 13, 2001

Melting Glaciers to Methane Gasses

Nearly 300 scientists from the U.S. Geological Survey will present papers and posters describing their earth-science research, during the annual meeting of the American Geophysical Union (AGU), at the Moscone Convention Center in San Francisco, December 10 – 14. 

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Image shows a man standing ankle-deep in a stream with an orange sampler
July 11, 2016

Methane Sampling in Stream

A USGS scientist samples a stream in Utah, looking for methane contamination. Credit: USGS.

Methane hydrate
April 11, 2016

Methane hydrate

Methane hydrate is sometimes called "the ice that burns" because the warming hydrates release enough methane to sustain a flame. 

Image: Gas Hydrates Burning
March 14, 2016

Gas Hydrates Burning

An image of gas hydrates burning. Gas hydrates are naturally-occurring “ice-like” combinations of natural gas and water that have the potential to provide an immense resource of natural gas from the world’s oceans and polar regions.

Attribution: Energy and Minerals
methane gas bubbling up from the seafloor, surrounded by mussels
December 31, 2013

Methane gas bubbles rise from the U.S. Atlantic Margin seafloor.

Methane gas bubbles rise from the seafloor – this type of activity, originally noticed by NOAA Ship Okeanos Explorer in 2012 on a multibeam sonar survey, is what led scientists to the area.

video thumbnail: USGS Gas Hydrates Lab
April 30, 2012

USGS Gas Hydrates Lab

Gas hydrates are a significant potential energy source occurring in ocean-floor sediments at water depths greater than 500 meters and beneath Arctic permafrost. The USGS operates a gas hydrates laboratory on its Menlo Park campus. This video features USGS geophysicists Laura Stern and Steve Kirby who relate details on how they study and create gas hydrates in their super-

Attribution: Energy and Minerals
Image: Methane bubbles trapped in thermokarst lake ice
October 1, 2011

Methane bubbles trapped in thermokarst lake ice

When ice-rich permafrost thaws, former tundra and forest turns into a thermokarst lake as the ground subsides. The carbon stored in the formerly frozen ground is consumed by the microbial community, who release methane gas. When lake ice forms in the winter, methane gas bubbles are trapped in the ice.

Attribution: Water Resources
Image shows marsh gas bubbling up from below

Marsh Gas

Bubbles of methane, also known as marsh gas, created by methanogens.