INTERPRETATION OF THE POTENTIAL ENERGY PROFILE

INTERPRETATION OF THE POTENTIAL ENERGY PROFILE

It could happen that the potential energy profile does not assume the shape of a bell but that does not mean that the procedure or the original concept is not correct.

Infact this aspect depend above all by the position of the basin.

If the basin is developed along the coast with an outlet section in the sea the shape of the curve will be a bell so as described in the previous pages while if the basin is developed along a slope the shape of the potential energy profile will be much more similar to a hook.

At last if the basin is posted close to at the top of a mountain the profile assumes the shape of a piece of a curved line.

That is due to the fact that the outlet section’s quote is not equal to zero in the second and in the third case.

If Hi is equal to 0 (zero) so the related Ep value is equal to zero while if the outlet section’s quote is different to zero so consequently related Ep value is different to zero.

To basins with outlet section’s quote equal to zero correspond bell shape profiles while to low quote outlet section so as in the pedemontan basins correspond profiles more similars to hooks than to bells.

In the case of hight and very hight quote of outlet sections so as in the mountain basins to these correspond a curved line profile.

As consequences of the change of the shape is the fact that the EQUILIBRIUM POINT disapears and this means that the entire slope of the basin starting from the CRITICAL POINT altitude to the outlet section is in erosion. 

So proceding upperhill erosional processes are active since to the CRITICAL POINT while proceding downhill erosional processes are active since to EQUILIBRIUM POINT.

It could happen also that the profile could be not properly regular as a bell’s shape.

In these cases the shape’s characterisitics depend by both the geological and the geomorphological history of the basin.

GEOLOGY

Consider for example a small or medium basin developed into a single lithology so as basins within badlands areas.

In this case particularity is that inside the related graph and along the potential energy profile the EQULIBRIUM POINT and the CRITICAL POINT have both the same X_COORDINATE and they are posted along the same vertical line.

The same X_COORDINATE means that processes need the same energy to be activated.

Infact:

- Proceding to upperhill from the outlet section and over the equilibrium point it is necessary to have a X_VALUE of potential energy to erode the bed of the river.

- Proceding to downhill from the apex of the watershed and over the CRITICAL POINT it is necessary the same X_VALUE of potential energy to erode the bed of the river.

GEOMORPHOLOGY

It could happen also that the profile present two maximum values one relative while the second aboslute and considering the evidences of the various realized application cases it result that usualy is due to the geomorphological history.

These particularities must be interpreted case by case.

BELL PROFILE

TIPICAL POTENTIAL ENERGY PROFILE OF THE BASINS WITH THE OUTLET SECTION TO THE SEA

TYPICAL ENERGY PROFILE WITH A BELL SHAPE WITH THE MINIMUM VALUE AROUND THE ZERO.

HOOK PROFILE

TYPICAL POTENTIAL ENERGY PROFILE OF THE BASINS POSTED WITHIN HILLY CONTEXT WITH OUTLET SECTION POSTED AT QUOTE DIFFERENT TO ZERO.

CURVED LINE PROFILES

PROCEEDING ALONG ALTITUDE THE PROFILE’S SHAPE IS MUCH MORE SIMILAR TO A CURVED LINE THAN A BELL SHAPE OR A HOOK.