Answer: It is Igneous rock
Explanation: I think that is what it is but not %100 sure
Pioneer species include bacteria and lichens that can grow on bare rock and help make soil. Secondary succession occurs in a formerly inhabited area that was disturbed. Soil is already in place, so pioneer species include small plants such as grasses.
The top layer would be most likely to have closer similarities to the organisms found today. hope this helps.
The potassium 40 to calcium or argon 40 half-life is 1.25 billion years so if this half-life is displayed then the age of 1.25 billion years would be valid. Half life is the time it takes for an isotope to decay into half its' amount and which in the process is losing its radioactivity.
