cries of kerogen arise from the swamp bc its less valuable and must be heated to extract oil and from what i've seen is often associated with oil shale,which is why cries of oil shale arise, when there is no kerogen or oil shale associated with zn's mj1 well

sweet is light -not heavy- in-sulphur - a good thing in both oil and iron

and light is easier to process partly bc of very little impurities and thus more valuable

so the oil zn encountered -though in non-commercial quantities so far,is at least a good quality oil,if they can find where a reservoir is hiding

https://www.thebalance.com/the-basics-of-crud...on-1182570

https://www.glossary.oilfield.slb.com/en/Term...rogen.aspx