Re: Where did all the oxygen in pre-cambrian Si dioxide likely originate

Dear Wayne,

The answer to your question: The stars made it!

It all starts with the Big Bang, really. The matter that resulted from the Big Bang consisted of only five elements: a lot of hydrogen and helium with very small amounts of lithium, beryllium and boron. These elements are the smallest of all the known elements (they are numbered 1 - 5 on the Periodic Table of the Elements). They eventually condensed to form the first stars in the universe.

The heat and pressure within the stars caused these five elements to fuse, producing the heavier elements carbon, nitrogen, oxygen and the rest of the elements up to iron ( elements #6 through #26). As the stars died out, they exploded, forming the remaining heavier elements ( cobalt through uranium) and spewed them all into space. The process of star formation and death repeated over the eons across the universe ( and still does) ultimately producing all of the elements that make up the earth.

The Earth condensed from a nebula containing these elements in the form of gasses, dust, asteroids, etc.

Thanks for the question!

* The Precambrian period spans the first 7/8ths of the earth’s history from 4.5 billion years ago when the first rocks formed to 544 million years ago when complex multicellular organisms had evolved.

**“Si dioxide”, or silicon dioxide, is the mineral quartz.

I borrowed heavily from a great website at the University of New Hampshire called The Interstellar Medium. They have many clear explanations on the top