Directional Drilling and Surveying Basics and Terminologies

Directional Drilling is a service that assists Exploration and Production companies reach their intended geological target by drilling and deviated wellbore. Slanted, directional and horizontal wells are types of deviated wellbores. The rationale to directionally drill a wellbore are economics or environmental. Directional drilling is performed with tools that intentionally deflect the drill string from the existing wellbore using measuring or surveying tools to determine the path and wellbore placement.
Directional Surveying is a service that determines the spatial positioning of a wellbore by processing survey tools raw sensor data and computing it into survey stations. Directional surveys determine the distance to a geological target, a legal or field boundary, or another wellbore or wellbores nearby. Surveys provide inclination, direction and tool orientation from gravity, magnetic or gyroscope sensors. Single-Shot, Electronic Multi-Shot, Gyro and MWD are types of directional surveying tools. In this paper we will explain the basics and terminologies for Directional Drilling and Directional Surveying.