(Update 11/4/17)
Two hours per group is good.
What seems to work is to have a talk by the buses first for 10 mins, then do the walk up around the rim for maybe 1 + 1/4 hour. A series of 10 minute walk, 5 minute talk repeated 5 times.
We can do some more talking and looking at rocks while the stragglers come in. They tend to string out on the walk, with some only getting half way up.
I can talk to them on those topics you mention. It tends to focus them if they have a list of questions to ask, which I respond to.
And hopefully I can get them to come up with some of the answers themselves.
Some questions could be:
Year 8 to 11 geography:
What causes volcanoes? (Continental drift, sea bed, subduction,)
(I also like to talk about formation and structure of the earth)
Are all volcanoes the same? (as above, plus: shield, scoria cone, maar,)
Differences between Mt Elephant, Mt Shadwell, Mt Rouse, etc. (Base rock and water, density, vent diameter, olivine, flow distance, )
How old is Mount Elephant and other Australian volcanoes? (Dating methods, aboriginal stories) (Qld 35mya to Mt Eccles, Tower Hill Vic 30,000ya, but some earlier. Mount Elephant now about 500,000 years.)
What was the land like here before the volcanoes? (Bores, xenoliths, aerial magnetic and gravity surveys, satellite Ar,U,K,Th decay) (soils, rocks, landform, Lismore/Derrinallum) (Granite, rounded quartz rocks, limestone, sandstone, magnetic ironstone, )
How have volcanoes changed the landscape? (Flows filled the valleys, created lakes and wetlands, soils different, trees replaced by grasslands, stony rises with shrubs and no eucalypts)
How has Mount Elephant changed since European settlement? (Grazing, fires, rabbits, weeds, mining, +/- trees, ownership, management)
How have mining regulations changed over time? (restoration bonds, staged mining and restoration, replanting)
How can the community be involved in Mt Elephant? (walks, events, work bees, consultation, publicity, schools, ...)
What could the future be?
Some other questions that I need not deal with, but they can think about are:
How is basalt used? (Buildings, roads, railway ballast, early stone walls, )
Why? (common, able to be cut and chipped and crushed, durable but hard, porous, )
Why do some craters have lakes and others do not? (above or below the water table)
At $10/t. what is Mount Elephant worth? How many $ already mined from the quarry?
How did people know exact locations before GPS? (trig points, compass, sextant, watch, and chain measures)
What distance to the hills and lakes? How to tell distance and angle?
Tertiary students Sustainable Landscapes can think about:
Forms of ownership of natural environments. (Covenants, shire, Parks Vic, conservationists,...)
Forms of encouragement of resource management. (Bush tender, Covenants, tax rebates, philanthropic grants, government grants, entry fees)
Likely effects of climate change. (temperature, fire, flood, wind, lack of funding, lack of habitat, )
Ways to mitigate effects of change. (Increase biodiversity,