Total natural gas rig count in the US (including conventional gas drilling) Shale gas is natural gas that is found trapped within shale formations. Shale gas has become an increasingly important source of natural gas in the United States since the start of this century, and interest has spread to potential gas shales in the rest of the world.
A stressor is a chemical or biological agent, environmental condition, external stimulus or an event that causes stress to an organism.[1]
1 Stressors = those life events or changes that are so serious or drastic that they require changes in the family system, for example, the death of a spouse, financial crisis, unemployment. 2  Distress = extreme psychological pressure resulting from facing repugnant and/or unenjoyable challenges.