资源环境科技发展态势分析平台

Increases in drilling efficiency pushed U.S. crude oil and natural gas production to establish new records of 12.2 million barrels per day (b/d) and 111.5 billion cubic feet per day (Bcf/d), respectively, in 2019. Using preliminary data for 2019, the average active rig count per month was 943, and the average count of new wells drilled per month was 1,400, according to Baker Hughes rig data and IHS Markit well data. Both the number of active rigs and the number of wells drilled were at the lower end of the range during the past 45 years, despite the record production. One factor that has contributed to the increase in production has been the ability to contact more of the formation using horizontal drilling. The average footage drilled per well was 15,000 feet per well in 2019, reflecting longer horizontal well lengths.

The number of U.S. oil and natural gas wells drilled each month per active rig has decreased since the peak in 1986 of 3.6 wells per rig per month. In 2019, an average rig drilled 1.5 wells per month. By drastically increasing the horizontal length of wells, producers have increased production despite using fewer rigs and drilling fewer wells.

Horizontal wells in the United States averaged about 10,000 feet of lateral length in the early 2000s but averaged 18,000 feet in 2019. Because horizontal wells now account for a larger share of new wells, the average linear footage per well increased from 6,000 feet to 15,000 feet during the same period.

The increased productivity of wells with longer horizontal lengths has more than offset the effects of rigs drilling fewer wells. Horizontal wells have more wellbore—the hole that forms the well—in contact with the producing formation, increasing the amount of crude oil or natural gas that can be recovered compared with a vertical well. The average rig was drilled 18,000 feet to 27,000 feet per month in 2019, almost twice as far as the active rigs in the early 2000s.

Horizontally drilled wells have become especially prevalent in shale and tight formations and have risen from about 2% of total wells drilled in 1990 to more than 75% in 2019. The number of new vertical wells drilled has decreased since its recent peak in 2008.

Horizontal wells have become the predominant way of drilling oil and natural gas wells in the United States, first outnumbering vertical and directional wells combined in 2015. In 2019, 75% of newly drilled wells were horizontal, and they averaged 18,000 foot wellbores compared with directional wells, which averaged 10,000 feet, and vertical wells, which averaged 4,500 feet.

Principal contributors: April Patel, Emily Geary