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.
Natural gas can also form from fossil plant material. During sedimentary rock formation the remains of algae and zooplankton are converted into a mixture of organic hydrocarbons known as kerogen. Over geologic time heat and pressure can convert kerogen into oil or natural gas.ossil fuels currently provide more than 85% of all the energy consumed in the United States. Crude oil supplies 40% of our energy needs and accounts for 99% of the fuel for cars and trucks.