DescriptionK-T-boundary.JPG English: The intermediate claystone layer contains 1000 times more iridium than the upper and lower layers. It is the boundary between
the boundary of main cardioid : c = c ( t ) = e Π ∗ t ∗ i 2 − e 2 ∗ Π ∗ t ∗ i 4 ≈ − 0.390540870218399 − 0.586787907346969 ∗ i {\displaystyle c=c(t)={\frac