Cyanobacteria are a group of photosynthetic prokaryotes (single celled organisms lacking membrane enclosed nuclei and organelles) that have been present in the fossil record for the last 3.5 billion years and are still abundant today. Cyanobacteria are the only group of organisms that split water molecules and release O2 into the atmosphere. They have been credited with initiating the creation of the oxygen rich environment which has made life as we know it possible. Cyanobacteria are widespread in our environment, but are particularly prolific in anaerobic and highly saline environments where they are protected from organisms who feed on them. The environments in which cyanobacteria thrive is also the environment necessary to the formation of oil producing sediments - decomposition does not occur in anaerobic environments. In these protected environments they grow into thick mats and often develop into stromatolites. Stromatolites can be described as mini-reefs that develop as successive generations grow on top of the remains of their predecessors. Living stromatolites can be studied in such places as Shark Bay, Australia and their presence in the fossil record provides scientists with important environmental keys to conditions in the distant past.

 
Timeline

The tables of geologic time that are commonly found are useful but, unfortunately, not an accurate depiction of the amount of elapsed time. These charts are constructed to fit a page, but what would a timeline built to scale look like? Let’s build one using the scale 1cm = 1 million years (you will see this scale is both too large and too small). We will also use the generally accepted 4.5 billion years as the age of the earth.

4.5 billion = 4,500 millions, therefore, our timeline would have to be 4500cm, or 45m, long. If we attempted to shorten the timeline to only include more pertinent events, we could begin the timeline at the beginning of the Palaeozoic Era; this would eliminate the Precambrian events, but our time line would still be 5.7m long. If we began at the beginning of the first time period that is important to the Lloydminster oilfields, the Devonian, the timeline would be 4m and 8cm long, still too long for any book

To shrink our timeline we could use a different scale, however, this creates another problem. Using the 1 cm = 1 million years scale and stretching recorded history to 10,000 years for ease of calculation, on our timeline this 10,000 years would be displayed as a dot 1/10th of a mm in size, too small to label. If someone lives to be one hundred years old we think they are ancient, but that would only be 1/10th of 1/10th of 1/10th cm or one micron on our timeline, many species of bacteria grow to 2.5 microns. Studying the earth can be very humbling.