In the oil industry measured depth (commonly referred to as MD, or just the depth), is the length of the borehole. In conventional vertical wells, this conincides with the true vertical depth, but in directional or horizontal wells, especially those using extended reach drilling, the two can deviate greatly. For example, at the time of writing (2012) a borehole in Odoptu field, Sakhalin-I, has the greatest measured depth of any borehole at 12,345 m, but most of this is horizontal, giving it a true vertical depth of only 1,784 m. For comparison, the Kola Superdeep Borehole has a slightly shorter measured depth at 12,262 m, but since this is a vertical borehole, this is also equal to the true vertical depth, making the Kola Superdeep Borehole deeper by a factor of 6.9.
Famous quotes containing the words measured and/or depth:
“I must remind you that our credulity is not to be measured by the truth of the things we believe. When men believed that the earth was flat, they were not credulous: they were using their common sense, and, if asked to prove that the earth was flat, would have said simply, “Look at it.” Those who refuse to believe that it is round are exercising a wholesome skepticism.”
—George Bernard Shaw (1856–1950)
“People who comprehend a thing in all its depth seldom remain true to it forever. For they have brought its very depth to light: and there is always so much nastiness to see there.”
—Friedrich Nietzsche (1844–1900)