Horizontal Drilling
While directional drilling has existed since the 1930s, its combination with hydraulic fracturing has changed the global energy landscape only in the past ten years. Advances in horizontal drilling technology have allowed producers to reach new depths, enabling the cost-effective exploitation of tight oil/gas formations, in what has been called the “Shale Revolution.” 1 Typical wells for oil and gas production are vertical – drilled straight from the surface of the earth to reach hydrocarbon reserves below ground. Directional or horizontal drilling allows producers more flexibility and precision in reaching and extracting oil/gas compared to vertical drilling. Horizontal drilling also reduces the ecological footprint of a drilling operation above ground by drilling in several directions from a single well pad.2
Schematic of horizontal drilling. (U.S. Department of Energy)
The most important application of horizontal drilling has been in exploiting shale plays across the United States, including:
- Barnett Shale, Texas
- Fayetteville Shale, Arkansas
- Haynesville Shale, Arkansas/Louisiana/Texas
- Marcellus Shale, Appalachian Basin
U.S. shale basins. (U.S. Energy Information Administration)
Horizontal drilling allows oil and gas producers to minimize surface impacts of development — being able to drill multiple wells from a single pad. However, by the same token horizontal drilling has been the subject of property/mineral rights disputes, as drillers have the ability to extract from neighboring parcels. Horizontal drilling has even been the subject of international tensions, most famously in 1990, when Iraq accused Kuwait of stealing its oil through the use of the technology, ushering the start of the First Gulf War.3
[1] “Development Tendency of Horizontal Directional Drilling,” DC Solids Control, Jan.18, 2013.
[2] “Glossary of Geosteering Terms,” Chinook Consulting Services (August 2010).
[3] “Iraq to Reopen Embassy in Kuwait,” ABC Inc., Sept. 4, 2005.
