long term, page-20

I'm no geologist so I decided to look up what they said is in the core, looks to me like they are really onto something here. I hope it drops to 1.5c again, I will get my avg down from 6c now. I have no doubts this will run again on results, down rampers trying to get in cheaper that's all.


An ignimbrite is the deposit of a pyroclastic density current, or pyroclastic flow. It is a hot suspension of particles and gases flowing rapidly from a volcano driven by having a greater density than the surrounding atmosphere. New Zealand geologist Patrick Marshall derived the term 'ignimbrite' from ‘fiery rock dust cloud’ (from the Latin igni- (fire) and imbri- (rain)), formed as the result of immense explosions of pyroclastic ash, lapilli and blocks flowing down the sides of volcanoes.

Ignimbrites are made of a very poorly sorted mixture of volcanic ash (or tuff when lithified) and pumice lapilli, commonly with scattered lithic fragments. The ash is composed of glass shards and crystal fragments. Ignimbrites may be loose and unconsolidated or lithified (solidified) rock called lapilli-tuff. Proximal to the volcanic source, ignimbrites commonly contain thick accumulations of lithic blocks, and distally, many show meter thick accumulations of rounded cobbles of pumice.

Tuff (from Italian tufo) is a type of rock produced by the eruption of volcanoes.

It consists of consolidated [1] volcanic ash ejected from vents during a volcanic eruption. Rock that has more than 50% tuff is called tuffaceous. The chemical and mineral composition of tuffs varies according to what was in the molten magma.