Joint – Large and relatively planar fracture in a rock along which there has been no relative movement.
Jurassic – Period from 200 to 145 mya that is divided into three epochs: 1) Early Jurassic Epoch had four ages: the Hettangian, Sinemurian, Pliensbachian, and Toarcian Ages. 2) Middle Jurassic Epoch had four ages: Aalenian, Bajocian, Bathonian, and Callovian Ages and 3) the Late Jurassic Epoch had three ages: the Oxfordian, Kimmeridgian, and Tithonian Ages.
Juvenile Gas – Gases that come to the surface for the first time from the deep interior.