The D of E bronze practice expedition has seen me out in the hills north of Dunkeld over the last couple of days. Apart from the anticyclonic weather which you can read about on 'Geography: My Place and Yours', I had lots of time to observe the landscape and 'do' geography. Reading any landscape and trying to explain how features were formed is not a precise science -you have to look for clues and draw on your knowledge of geomorphology to interpret those clues.Having almost completed the Higher course, you should all be able to look at the loch called Children's Loch above and make some suggestions about how it might have been formed. Here is what it looks like on the 1:25000 map...
Image reproduced with kind persission of the Ordnance Survey
It is likely that the neighbouring Dubh Loch was created in the same way. Clue.. glaciation, retreating ice....
Just to the south are three other small lochs - Dowally Loch, Rotmell Loch and Mill Dam...
Image reproduced with kind permission of the Ordnance Survey
I don't think their origin is the same as Children's Loch. If you look at the map, you can see that they lie in a very straight line. That's quite unusual and I reckon it has something to do with the structural geology of the area. There is a broad broad fracture zone in this area associated with the Highland Boundary Fault and so I think these lochs could be occupying a fault-guided valley. Glaciation, however, could also have fashioned the valley . As you can see below, the south eastern end of Rotmell has a strange shoreline...
A ramp of smooth rock rises gently from the water's edge before dropping away in a steep, craggy slope in the downvalley direction..
There has almost certainly been abrasion and plucking going on here - abrasion as the ice came down the valley, digging out the hollow later to be occupied by the loch and then grinding its way up an outcrop of hard rock lying in the valley before plucking away at the down-ice side as the pressure was released. Hopefully this is ringing some bells?!!
