In general, irregular periods are very common during the perimenopause. The most common early menstrual irregularity noticed in the perimenopause is a shortening of cycle length.
Abiogenic petroleum origin. Abiogenic petroleum origin is a term used to describe a number of different hypotheses which propose that petroleum and natural gas are formed by inorganic means rather than by the decomposition of organisms.
Hydraulic fracturing, a technique used to extract natural gas from deep shale formations, has been employed for decades. However, technology advancements are enabling access to vast quantities of previously unrecoverable natural gas in regions where it is not a familiar practice.