halt!, page-25

re: halt! -uraniumbull- Cjames.

Uranium can form in sedimentary, igneous or metamorphic rocks.
Olympic dam is the worlds largest uranium deposit and it is a huge caldera or volcanic vent. The Marathon deposits are similar in that they were formed 1500m years ago (same time as olympic dam) by the explosive venting of volcanic gasses from deep in the earths crust. Sedimentary deposits occur when uranium is dissolved by water from eroding source rocks and redeposited in oxygen depleted sediments like peat bogs or swamps.

All the best.