David Perotto posed the question: "Methane in Dimock came from biogenic methane, not thermogenic. Do you know/understand the difference?"

Obviously David knows the answer, but do you?

The reality is that the vast majority of the populace likely do not know that Natural Gas is primarily methane, let alone appreciate that there are multiple mechanisms by which methane is formed.

This lack of knowledge has allowed “False Casandras”, “Fear Mongers”, “Yellow Jounalists”, “Chicken Littles” and assorted “Trolls” to inflame and solicit a cadre of followers amongst the uneducated. There seems to be some hardwiring of the human brain that causes us to seek out a religious “experience”; for some that religion has become the “Church of the Anti-fracer”. Once indoctrinated into the Dogma of that religion, the “true believers” become immunized against subsequent facts or reason; nothing that anyone says can shake their “beliefs”.

But, for those still capable of independent thought, I offer the following:

Lack of knowledge has allowed the “passing off” of the presence of biogenic methane as thermogenic methane; Dimock is a prime example of where early confusion resulted in false accusations (confusion that obviously continues in the minds of many to this day).

Let us start out with definitions of some of the various origins of Methane:

Biogenic Methane: Natural gas can be formed through the transformation of organic matter by tiny microorganisms; this type of methane is referred to as Biogenic Methane. Tiny methane-producing microorganisms, chemically break down organic matter, produce methane as a byproduct of their metabolism. These microorganisms exist in areas near the surface of the earth that are void of oxygen. Like microorganisms also live in the intestines of most animals (from termite to elephant), including humans (I still have pleasant childhood memories of walking barefoot through the pastures on a cold morning, hopping from one fresh cow patty to another as the methane bubbled though the still warm patties – warming my cold feet as the patty squished between my toes). Formation of methane in this manner usually takes place close to the surface of the earth, and the methane produced is usually lost into the atmosphere. However, this methane can be trapped underground, recoverable as natural gas. This biogenic gas can be present in Spring or Well Water.

Another example of biogenic methane is landfill gas. Waste-containing landfills produce a relatively large amount of natural gas from the decomposition of the waste materials that they contain.

Several generations ago, biogenic methane would have been referred to as ”Swamp Gas”. Since Biogenic Methane is produced by shallow subsurface bacteria, it is a common natural source of methane gas encountered in water wells that tap groundwater aquifers.

Thermogenic Methane: Thermogenic Methane is formed when organic matter (remains of terrestrial or marine plants or animals) is incorporated in sediments and is compressed beneath the earth, at very high pressure for a very long time. Similar to the formation of oil, thermogenic methane is formed from organic particles that are covered buried along with other sediment. Over time, more and more sediments are piled on top of the sediments containing organic matter. These sediments exert a great deal of pressure on the organic matter, compressing it. Compression, combined with high temperatures found deep beneath the earth, breaks down the carbon bonds within the the complex molecules of the organic matter. As one gets deeper and deeper under the earth’s crust, the temperature gets higher and higher. At low temperatures (shallower deposits), more oil is produced relative to natural gas. At higher temperatures, however, more natural gas is created, as opposed to oil. That is why natural gas is usually associated with oil in deposits that are 1 to 2 miles below the earth's crust. Deeper deposits, very far underground, usually contain primarily natural gas, and in many cases, pure methane – as a result of the oil being thermally “cracked” into methane. Over most of the Marcellus Shale, at some point in its geologic history, it was subjected to depths such that now only Methane is present. In areas where the Marcellus was not (at any time) buried as deep, Natural Gas Liquids (NGLs) are still present alongside the Methane.

Coal Bed Methane: Coal Bed Methane exhibits elements of both Biogenic Methane and Thermogenic Methane. Coal Bed Methane is present in the shallow coal measures of much of the Appalachian area. This Coal Bed Methane frequently migrates into nearby Springs and groundwater aquifers. Methane bubbling up in Streams and in Springs has been documented in the Dimock area for several centuries.

Another way in which methane (natural gas) may be formed is through abiogenic processes. Extremely deep under the earth's crust, there exist hydrogen-rich gases and carbon molecules. This form of methane is not worth considering, as it is outside the scope of this discussion.

Yet another way in which methane (natural gas) may be formed is through the direct creation by living plants. Recent work at the Max Planck Institute of Physics has detailed this source of Atmospheric Methane. This form of methane is outside the scope of this discussion.

Now, getting back to Dimock.

When the drilling of the Marcellus commenced, the (long ignored) presence of Methane gas in the Dimock area’s water was “discovered” by newcomers. Ignorant of History, Geology, Chemistry (and science in general), Marcellus Shale drilling and fracing became a “bête noire” for various Luddites.

As Methane is a colorless, odorless gas (made up of a simple molecule), the origins of a particular presence of methane is not immediately apparent. The hue and cry of a very vocal minority overcame the cautions of the rational. Sensationalism and Yellow Journalism ran roughshod over reality. The Legend of Dimock Hollow  was created.

Though not a trivial exercise, there are means of analyzing methane to determine whether its origins are biogenic or thermogenic (or Coal Bed Methane). Carbon Isotope analysis and methane/ethane ratios have established that the source of the methane in Dimmock’s water is from historic Biogenic and from Coal Bed Methane sources. As the gas produced from the Marcellus Shale is strictly Thermogenic Methane; chemical analysis disproves the Marcellus Shale (and fracing of that shale) as a possible source of the methane in Dimock’s water.

Repeated analyses of Dimock’s water has not only demonstrated that it is “safe”, but also indicates that what is present in the water is not related to the drilling and fracing of the Marcellus Shale.

Sadly, the teachings of the Church of the Anti-fracer has made its way into public lore as yet another Urban Legend (along with Bigfoot, Yeti, Loch Ness Monster, Tooth Fairy, Alien Abduction). Regrettably, every so often a Troll crawls out from under their bridge and dredges up the Legend of Dimock Hollow in order to frighten the kiddies.

JS