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]
Definition of Stress Stress is defined as âa state of psychological and physiological imbalance resulting from the disparity between situational demand and the individual's ability and motivation to meet those needs.â Dr. Hans Selye, one of the leading authorities on the concept of stress, described stress as âthe rate of all wear and tear caused by life.â