Army of Iron Workers
Cyanobacteria
What would we do without steel? Can you imagine a world with no cars, bridges, rails, sky scrapers, nails, or paper clips – each typically made from steel? Steel begins with iron ore. First iron ore is mixed with carbon-coke, the carbon resulting from purified coal, to form “pig iron”. Pig iron is melted in an oxygen-rich chamber; compounds such as silicon, manganese and phosphorus are added to the melt to remove impurities and to add properties to the steel. Molten steel sinks to the bottom of the ladle and impurity-rich slag floats on top; steel is poured into slabs, blooms and billets while the slag is carted off to the slag-heap.
Earth has always contained vast quantities of iron, most of which is concentrated in its core 7000 miles beneath the surface. Billions of years ago, the Creator foreknew mankind would need lots of iron to make things, but there was a little problem – the iron was broadly dispersed as a trace element throughout the oceans and continents. It needed to be concentrated into iron-rich deposits if it were ever to be of any use to man.
Imagine being a ‘fly-on-the-wall’ as the Godhead (Father, Son and Spirit) were in council discussing plans to provide abundant resources of iron for humanity. The conversation might have gone something like this:
“(Father) With all the creativity we’ve endowed the future sons of Adam, it shouldn’t take very long before they will progress from primitive stone structures and implements to the more advanced benefits steel can give them. We planned well to seed the Earth with lots of iron; now it’s time to collect it into rich deposits. What are your thoughts?... (Son) I’ve given the matter a lot of thought; here’s something to consider. Everything is already in place; Earth’s oceans have become very acidic with iron washed in from erosion of the volcanic continents; the seas are brimming with colonies of anaerobic (thrive in an oxygen-poor environment) bacteria. Let’s deploy this army of single-celled cyanobacteria to purge the iron from the seawater, then deposit it on the ocean floor... (Spirit) Sounds reasonable to me. I believe the plan would be most effective if we were to utilize two key components: oxygen and sunlight. The army of cyanobacteria needs to be equipped with a mechanism to convert sunlight into energy; let’s call it “photosynthesis”. The metabolic waste product of photosynthesis is oxygen. Oxygen released from cyanobacteria into the water will bind with iron ions, forming into the heavy metals hematite (Fe2O3) and magnetite (Fe3O4). These iron-rich minerals will gradually pile up on the ocean floor and form huge ore deposits, patiently set aside for their future discovery by mankind… (Son) Fantastic, but we know oxygen is toxic to anaerobic cyanobacteria. Once these bacteria saturate the water with oxygen, won’t they be poisoned by their own waste, die out, and eventually become extinct?... (Father) No problem, we have a plan for that, and we get the double blessing of a cleaned-up ocean filled with oxygen available to be consumed by all of our soon-to-be-introduced lifeforms – coral, trilobites, fish, etc.”
Banded Iron Formation (BIF)
Scientists believe this to be the most plausible scenario. And indeed, colonies of oxygen-producing cyanobacteria were poisoned by their own waste and nearly died off. The evidence for life and death cycles is preserved in “banded iron formations”, thousands of alternating layers (bands) of iron and flint. Simplified cycle:
- Start with an acidic ocean filled with iron ions; the ocean is anaerobic (oxygen-starved); Earth’s atmosphere is also less than 1% oxygen.
- Colonies of anaerobic, photosynthetic cyanobacteria begin to grow, pumping copious amounts of oxygen into the seawater.
- This oxygen then purges iron ions from the sea to form into minerals like magnetite and hematite, which fall to the ocean floor and form bands.
- Cyanobacteria pump so much oxygen into the ocean that it becomes aerobic (oxygen-rich); poisoned, the colonies die off.
- Iron and oxygen continue to combine, until the ocean again returns to an oxygen-poor state.
- Meanwhile, erosion of the continents washes fresh iron and silica-rich sediment into the ocean.
- Without oxygen in the water, iron minerals can’t form; thus, only silica is deposited on the ocean floor, forming a silica band.
- New cyanobacteria colonies can become re-established in an oxygen-poor ocean, starting a new iron-band cycle.
Over time, and with immense pressure from overburden, the alternating layers of silica and iron hardened into rock. Today, BIFs are the world’s major source for iron ore. So, are BIFs the random outcome of a long string of natural ‘coincidences’, or might they have been the plan of an Intelligent Designer? For me, the litmus test is:” is there purpose behind the process?” Purpose always points to the Creator.
