A Brief Petroleum History

A Brief Petroleum History There are many places where oil seeps out of the ground. Bitumen produced from such naturally occurring crude oil has been collected and used since ancient times, both for lighting and medicine, and by the Greeks even for warfare. In some places, for example Germany in the 1800s, small mines were dug to get at the oil. Before 1859 oil was also recovered from coal for use in kerosene lamps. It was not until Edwin Drake’s exploits in 1859 at Oil Creek near Titusville in West Pennsylvania that oil was recovered in any quantity from boreholes.

He drilled a well about 25 m (70 ft) deep which produced 8–10 bbl/day, a huge production rate compared with anything earlier. A few years later there were 74 wells round Oil Creek, and the USA’s annual production had risen to half a million barrels. Outside the USA the calculated total production at that time was maximum 5,000 bbl. In 1870 production had increased tenfold, with 5 million bbl from the USA, and 538,000 bbl from other countries. In southern California oil production started early in 1864 (in Santa Paula), but for many years oil was mined by driving shafts into the oil-bearing strata because it was so heavy and biodegraded that it would not flow in a well.

In its infancy, oil exploration consisted largely of looking for oil seepage at the surface and drilling in the vicinity, which did not require much geological knowledge. It was then realised that oil and gas occur

where layers of sedimentary rocks form domes or anticlinal structures since petroleum is less dense than water and a low permeability (seal) layer is needed to prevent the oil and gas from rising and escaping. This led to extensive geological mapping of anticlines and domes visible at the surface, particularly in the USA.

It was also found that oil fields had a tendency to lie along structural trends defined by anticlines or faults and this “rule” was used in prospecting. This is also often the case with salt domes, which became important prospecting targets. Oil production developed rapidly up to the end of the nineteenth century, and more systematic geological principles for prospecting were gradually developed.

The geological information which one obtains at the surface is often not representative of the structures deeper down. Structures which are not visible at the surface could be mapped by correlation between wells using logs and cuttings from the drilling. One method was to measure the depth of particularly characteristic strata through analysis of cuttings in different wells. Improved electrical measurements (logs) from wells, developed during the 1920s and 1930s, made the whole effort much simpler because they provided continuous vertical sections through the rocks.

The first logs were simple recordings of how well rocks conduct electrical currents (resistivity), and later also gamma logs recorded the gamma-radiation emitted by the different sedimentary rocks. The USA maintained its position as the major world producer of oil and gas well into the twentieth century. Americans thus became leaders in the development of oil technology, which today is strongly reflected in the industry’s terminology.

USA also rapidly became the world’s greatest consumer of oil and gas, and now has to import at least 60% of its oil consumption despite still having a large home production (8 million bbl/day). The US consumption (21 million bbl/day) is a very large fraction of the total world consumption (90 million bbl/day) It was first in the 1930–1940 period that the industry became aware of the vast oil resources of the Middle East, which now account for about 60% of world reserves. Since then this region has dominated oil production.