How did loam and marble originate and in what geological time period did this occur?

Answer

Dear Sarah,

Loam and marble are two very different deposits/rocks. Loam is a deposit that mainly consists of fine-grained particles (silt size fraction, 2 to 64 µm) and which is mainly deposited by wind or rivers. In principle, loam can always arise, as long as the conditions are right. In Flanders we mainly find these deposits in the Flemish Valley, going from roughly the north of Brussels over Lokeren to Terneuzen. This happened after the last ice age, when the valley was formed.

Marble is a metamorphic rock. It is formed by putting limestone under high pressure and temperature, which can destroy the original structures and even fossils. Here too, marble can be created at any time when the conditions are right, this is often accompanied by subduction of rocks. This ensures that they end up at a greater depth, where the pressure and temperature is high enough. In Belgium we find marble in some places in Wallonia and these were formed during the Paleozoic era.

If you want to know more, feel free to contact me!