A Brief Introduction to the History
A Brief Introduction to the History of Natural Gas Extraction
by Jennifer J. Halpern, July 30, 2010
Seemingly mysterious flames from rocks revealed natural gas to early humans. In Iran and Azerbaijan, burning natural gas seeps fueled early Persian fire-worship as early as 2000 BCE. A thousand years later, a Greek priestess declared that an "eternal" flame on Mt. Parnassus empowered her to foretell the future, and became known as the Oracle of Delphi. From those days, natural gas has changed lives.
This article illustrates how we seek natural gas with increasing ingenuity and skill. Once we depleted easily accessible sources, we reached elsewhere for it. Adapting exploration and extraction techniques from other types of drilling, operators also created new technologies. Their wells eventually encroached on the homes and environment of their own customers, leading to increased demands for regulation and policy.
The article also examines how New York State natural gas history led to the Marcellus shale superfield controversy. Lacking an Oracle, we depend on education and accurate information to help resolve the issue. This history may help us understand why operators use certain techniques, and why this superfield creates special challenges. Regulations will require another article.
Early Drilling: Searching for Salt and Water
Drilling for salt (valuable for preventing food spoilage) and water began early in human history. Egyptian pictographs of drilling date from around 3000 BCE; and there are remnants of technical developments in drilling in the Sichuan province of China starting 500 years later[i].
Underground natural gas reservoirs remained commercially undeveloped until the 1800's, when both China and the US recognized the potential of natural gas for heating and illumination (respectively). In China, targeted natural gas drilling began when the salt industry ran out of wood for heating desalination pans. American entrepreneurs saw the potential of this oil well byproduct for lighting homes, streets, and businesses. The first well drilled specifically for natural gas was 27 feet deep, and completed in Fredonia, NY (Chautauqua County) in 1821, by William Hart. Hart also developed a gas meter and pipeline, selling the gas to light an inn. Many more shallow natural gas wells followed in the Chautauqua shale belt, each servicing only one or two nearby facilities. Travelers detoured to see this "wonder[ii]".
Other countries also searched for natural gas during the 19th century. In 1835 a well in Shenghai was the first in the world to exceed a depth of 3,281 ft. In comparison, the deepest well in the United States at that time was 1,641 ft deep[iii] . Wells at least 2,000 feet deep fueled the Sichuan province economy with brine and natural gas. Many such wells were still producing in 2000[iv].
The Development of Natural Gas Drilling Techniques
Vertical, Percussion Wells. The first natural gas wells were vertical, adapting technology from oil and water well drilling. The 1800's standard was percussion (cable tool) drilling. A heavy metal bit repeatedly struck the rock, until it released a pocket of gas (if gas existed.) Wood-fired boilers powered these drilling tools, and derricks hoisted the drill. Operators lowered the drill through a drive pipe, or a conductor, of 10-foot-long sections to prevent cave-ins[v]. The introduction of steam power increased the efficiency of percussion drilling. The deepest known well using cable tool drilling was 11,145 ft, completed in 1953 in New York State. Shallow wells in the Appalachian Basin still use this method[vi].
Rotary Drilling. Rotary drilling features a sharp, rotating metal bit that drills more efficiently through hard rock than percussion. It is useful in deeper vertical wells, where high downhole pressure may block percussion. Early rotary drill patents in the 1830's involved a mule walking in a circle, attached to the drilling device[vii]. More spectacularly successful was the 1901 Spindletop oil well in Texas, which utilized a rotary drill. That gusher triggered development of every aspect of drilling[viii]. Modern rotary rigs are diesel or powered by natural gas engines or turbines. Innovations improved hoisting, rotating equipment, and the circulating system. Circulation involves liquids with additives that cool and lubricate the drill bit, remove debris, and coat the walls of the well with a mud cake to help prevent cave-ins before the casing is installed. The fluid circulates through the bit and back up the well to the surface.
Exploration. The same logic that drew Higgins and Lucas to drill in the Spindletop salt dome swiftly enticed explorers to improve their ability to locate reservoirs of gas (and oil). A brief introduction to exploratory techniques is at the Natural Gas Organization website, http://www.naturalgas.org/naturalgas/exploration.asp.
Directional/Slant Drilling. Exploratory data might indicate that a reservoir is under a railroad, lake, private property, or someplace else where drilling pads couldn't be located. Some reservoirs were long and thin, difficult to tap vertically. Directional (or slant) drilling was the next innovative step, first used in a 1929 Texas oil well by the company Texon. Using the flexible pipe developed for the rotary systems, and repeatedly changing the drill's angle towards the rockface, a drilled curve could reach sources from platforms located hundreds of horizontal feet away. Russia and China also embraced the technology in the 1950's. However, slant wells didn't become commercially viable here until the 1980's, following other drilling advances, such as electronic communications permitting monitoring the bottom of the drill hole remotely.[ix]
Horizontal Drilling: Long radius slant wells may take 2,000 feet to bend from the vertical to the horizontal. Quicker turns occurred after the steerable downhole motor appeared in the 1970's. This became more commercially viable about 20 years later, by which time a steerable drilling bit could make a 90 degree turn in only a few feet. Horizontal drilling allows one large drilling pad to service many wellbores, located only as far apart as necessary for protection of the wells, rather than basing spacing on the radius of the curve. The steerable motor prevents the drill from crossing other wellpaths.
Horizontal drilling is more effective than vertical drilling when the fractures (or joints) in the shale are themselves vertical, as in the Marcellus. Horizontal drilling is likely to cross vertical fractures.
Hydrofracturing. Increasing demand for natural gas, considered a "cleaner" alternative to some other fuels by the '80's and '90's, led operators to seek extraction of gas from tight, or dense, "low permeability" shales[x]. Hydrofracturing shale releases liquid or gas trapped within the rock. Another application of this technique increases water well productivity, and is still used. Water pumped at high pressure down an existing well widens and extends the fractures in the bedrock, increasing the network of water-bearing fractures supplying water to the well[xi]
Hydrofracturing dense shale involves a similar, but more intensive, process. Early hydrofracturing sometimes involved dynamiting the rock below the surface. Today, slickwater (water with additives that inhibit rust and micro-organisms, and that reduce friction between water and the well) and proppants (sand, glass beads, or epoxy, which hold the new fractures open) bombard the shale at high pressure[xii]. Cleanup -- including monitoring what happens below the surface -- is a bigger concern today than in the past, influencing materials used and the cost of the process.
Hydrofracturing was used successfully on the dense Texas Barnett Shale in the 1990's. Other rig operators subsequently adapted the techniques. Only one rule predominates: Every application differs. Adaptations vary depending on qualities of a particular shale, of rock above or below it; on whether an aquifer is nearby; or if a well is close to residences. Clean up requirements also vary. The radioactive and heavy metal content of the Marcellus, for example, is different than that found in other tight shales, and means operators should monitor waste water for radioactivity. Traditional uses for the flowback, like road cleaning or desalting, may not be advisable with Marcellus waste.
Drilling in New York State
Hart's original well produced until 1859[xiii]..Over time, depletion of many wells triggered exploration of deeper sources, such as the Medina Formation sandstone in Erie, Chautauqua, Cattaurgus, Genesee, and Ontario Counties. Otsego County's wells became commercial in 1889; and in 1896, Onondaga County well production was marketed. Improved transportation infrastructure brought natural gas to distant customers. Depleted wells, sites where gas or oil had already been extracted, were common: the first gas storage facility, opened in 1916, was in a depleted field, south of Buffalo[xiv].
By the late 1920's, these new reservoirs were producing less, so gas companies drilled even deeper in Allegany, Schuyler, and Steuben Counties. Oriskany sandstone in Schuyler Country yielded commercial production in 1930. But by 1940, Western New York was importing gas from other states.
The economic climate made NYS drilling possible again in the late 1960's, briefly tapping gas deposits in the Onondaga Formation, an ancient reef. By the 1970's, hydraulic fracturing enabled operators to reopen some New York State fields by stimulating "tight" gas sands[xv] in the Medina group, formerly thought to be unproductive and "played out."
New exploratory techniques and hydrofracturing in 1985 made the once unattractive Trenton-Black River shale productive. Since the late 1990's, this layer has been the leading producer in parts of Pennsylvania and in some parts of New York.
The complicated history of natural gas regulation is difficult to summarize. Some regulation resulted from problems encountered by operators, nearby residents, or advocates for the environment around the wells; other regulations led to drilling innovations. Some regulations were controversial, potentially offering loopholes for noncompliance. Complicating all of this is that within the same community, one neighbor might celebrate the drilling, and another might curse it. A summary history of regulation will have to be discussed in a future article.
Into the Future
If we continue to use natural gas, we need environmentally sustainable, responsibly-managed drilling. Achieving this goal is challenging. The history of natural gas extraction (like that of so many other resources) is one of demand leading to depletion leading to technical improvements; this in turn leads to an outcry for education, responsibility, and sensible regulation. It may also serve as a reminder that some approaches, rather than being thought of as inevitable next steps, might benefit from reconsideration.
[i] Mark Kurlansky Salt: A World History; naturalgas.org.
[v] Giddens, Paul H., Early Days of Oil, Princeton University Press, 1948. In the US, this ws E. Drake. In Sichuan China, 2,000 years earlier, the drillers learned the same lesson and used bamboo
[ix] https://www.dmr.nd.gov/ndgs/Newsletter/NL0308/pdfs/Horizontal.pdf; Horizontal Drilling, Lynn Helms, DMR Newsletter, V. 35(1)
[x] Dense shales have tiny pockets of gas that are not connected, so the gas doesn't flow easily once the rock is drilled. If the rock is fractured, these pockets release the gas along the fracture, and the gas can be drawn into the well through pressurization changes.
[xi] Hydrofracking Wells, American Ground Water Trust, in The American Well Owner, 2003(2).
[xii] ALL consulting, sept 2008)
[xiv] The Zoar field. http://www.dec.ny.gov/docs/materials_minerals_pdf/nyserda2.pdf
[xv] "Tight gas sands" are also referred to as "low permeability sands." Tiny pockets hold gas, but the gas can't be released easily unless the rock is cracked so that the gas can begin to flow.