Basin

It was fallen in

Not cavernous
or hollow

Nothing had eroded
It was there
It remained
just below
where it had been

There
low slung
prolapsed
Deeper
than an indentation

A tragedy
surrounding it
The history of the thing
stretching back
sinuous
to the level surface
Still traceable
It had not merely
dropped

It was fallen in

A collapse
without rubble
or trapped men
Though undeniably
a point of impact