One of California's oldest oil fields will get a chance for a new lease on life with modern technology.
The state of the art technology that could set the stage for a revival of giant McKittrick field in the southern San Joaquin Valley is a horizontal well to be drilled by Texaco Exploration & Production Inc.
Texaco's 250H Shamrock, in 19-30s-22e, Kern County, will bottom under the California Standard lease 1/2 mile southeast from the surface drill site. Estimated true vertical depth is 1,260 ft, measured depth 4,050 ft.
If there is anything in a name, Texaco's well may open a new chapter at McKittrick. The first gusher drilled in the field some 100 years ago also bore the Shamrock name.
The general area is one in which numerous tar and oil seeps attracted the attention of prospectors at least as far back as the 1860s. Early approaches involved mining methods brought down from California's Mother Lode mines.
Miners largely ignored the oil that later proved to be the real bonanza, focusing instead on asphalt. Some asphalt was mined from open pits, some from tunnels and shafts more than 300 ft deep. From a depth of about 80 ft in one shaft, a pure column of asphalt 10 ft high and 6 ft in diameter was shipped intact to San Francisco, where it was displayed at the 1893-94 Midwinter Fair.
Raw asphalt was refined in open kettles. Wood was scarce, and refiners sometimes used as fuel the oil-impregnated fossil bones of sabretooth tigers, camels, horses, and other prehistoric animals found with the asphalt.
Much of the asphalt was used for paving streets, some greased skids for logs in logging country, and some was used for sidewalks in San Francisco, where at one time the McKittrick asphalt brought as much as $30/ton.
In 1896, a new chapter began when Klondike Oil Co.'s Shamrock gusher blew in flowing an estimated 1,300 b/d. The depressed price of crude oil that followed forced Klondike to abandon development. Real development did not begin until 1898, with production that year of 10,000 bbl of oil.
Production peaked in 1909 at 5.8 million bbl of oil, an average of 15,910 b/d. The record lasted for 56 years until 1965, when the field with the advent of steam injection produced 8.3 million bbl. The following year, McKittrick produced 11.4 million bbl of oil, an average of 31,200 b/d, setting a record that still stands.
McKittrick field has produced 276.7 million bbl of oil and 199.7 bcf of gas. Estimated reserves are 7.1 million bbl of oil and 6.1 bcf of gas.
The figures do not include oil-bearing Diatomite shale that crops out in a part of the field's main area and is estimated to hold 380 million bbl of heavy oil believed recoverable through open pit mining.
Copyright 1996 Oil & Gas Journal. All Rights Reserved.
