Sunday, 5 June 2016

Day 05; #30DaysWild - Geological Conservation

I have been a member of a geological conservation group for a few years now, so today for Day 5 of #30DaysWild I joined them for a geoconservation session at one of our sites in Rubery, south Birmingham! This exposure features two rock types, the Lickey Quartzite and the Rubery Sandstone. The boundary between the two units is called an unconformity and it represents a missing period of time. The Quartzite is approximately 485million years old, and the Sandstone is about 435million years old, so the unconformity covers a timespan of 50 million years!

This may have been caused by a period of none deposition (no new rocks being laid down), or any rocks that were lain down have been eroded (removed) over time. There are lots of features in this rock face that suggest erosion; there is an erosion surface to the Quartzite, and lumps of Quartzite can be found in the Sandstone which suggests there were loose lumps around.

By simply stepping foot on this exposure I had travelled back in geological time by 485million years old, and by moving from one rock unit to the other I spanned a gap of 50million years. SO COOL. Geology is amazing, never let anyone tell you otherwise!

Two clay layers (pointed out by the trowels) seen in the Rubery Sandstone

The unconformity, marked by the trowel.

Every June the Wildlife Trusts run a campaign called 30 Days Wild. This year I shall be taking part! It is my first time doing the challenge, and I’ve been planning lots of things to do over the month. The idea is to encourage wildness, exploration and an involvement with the natural world. The daily things can be anything, from walking barefoot, to doing outdoor yoga, or growing veg to hunting out woodlice under a stone. Little things that help you reconnect with nature!