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Early Prospecting - Modern Exploration Always a Messy Business - Modern Production Pipelines, Tankers, Trains, and Trucks Turning Crude Into Commodities

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Exploration: Early Prospecting

For thousands of years, when oil was more of a curiosity than a necessity for most of humanity, it was found primarily at natural seeps, where liquid and gaseous hydrocarbons leak from the ground much like water flows from natural springs. Coastal California is one place where such seeps occur frequently, and the La Brea tar pits near downtown Los Angeles is an example familiar to most Americans. At La Brea and other seeps, oil tends to be blackened and thickened by oxidation and bacterial attack, often flowing in small quantities with a tar-like consistency. While this was sufficient for traditional and pioneer uses such as sealing wooden boats and greasing wagon wheels, the explosive development of the modern oil business would soon require a much greater and higher quality supply.

In 1859, with the well drilled by "Colonel" Edwin Drake in Northwestern Pennsylvania, the petroleum business began the industrial exploitation of pools of oil underground. Although early prospectors certainly studied the geological theories of the time, they also relied heavily on methods that often had as much to do with personal knowledge, experience, and luck as they did with geology. Prospectors drilled near seeps, looked for oil residues in rock samples, and sought out natural gas leaks that could be set aflame. Some even found oil by accident while digging or drilling for water.

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The Sherman oilfield, in California, was bustling with activity circa 1910.
These first wells in Pennsylvanian and Appalachia required that the oil be pumped to the surface, and quantities were miniscule by today's standards. Rumors of wells supplying 50 barrels per day would draw prospectors in droves. By the early 1860s, drills tapped the first freely flowing well in Pennsylvania, providing oil at the then-astounding rate of 3,000 barrels per day. Soon, annual production shot up statewide, from 450,000 barrels in 1860, to 3 million barrels in 1862.

The observational techniques for locating oil -- often practiced by geologists and non-geologists alike -- prevailed for decades. One of the greatest oil finds of all time was spearheaded by Patillo Higgins, a self-educated, one-armed mechanic, who had a persistence bordering on obsession that the strange hill called Spindletop, near Beaumont, Texas, had oil beneath. His hunch proved correct when, in January, 1901, the first true "gusher" was found there beneath a geologic feature now known as a salt dome. Salt domes originate when salt -- which is more buoyant than surrounding rock -- rises through the sedimentary layers above, piercing and bending them upward, forming ideal traps for oil and gas to collect as they seep and flow toward the surface.

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This document from 1865 certifies ownership of one share of stock in the Spondulix Petroleum Co.
The discovery at Spindletop -- where the first rig produced as much as 75,000 barrels per day -- was by far the largest to that point. And the oil boom that followed signaled the shift of the oil business from the place of its origin in the Northeast to its new center in Texas and Oklahoma.

The man who struck black gold at Spindletop, John Galey, was one of the most famous and successful of a breed of oilmen known as "wildcatters." He and other wildcatters, then and now, tend to drill for oil on the basis of relatively little geologic information, basing their livelihoods on the idea that holds an important truth even today: Despite the progress of geology as a means of predicting the location of oil, its measurements and theories are indirect and often imprecise. Any assessment has some degree of uncertainty, and the drilling of wells with no oil -- "dry holes," in industry parlance -- is all too common. In Galey's words, the only geologist who can ever really tell where oil is to be found goes by the name of "Dr. Drill."

-- Edwin Adkins

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