Are there examples of diverse departure assessment departures in the US or Canada?
A diverse departure is a default departure procedure, named "omnidirectional" by ICAO.

To answer your question: It is normally not published. The only thing that is required on aeronautical publications is a wording preventing or limiting the use of this procedure.


  BUCKLEY AFB (KBKF),  AURORA, CO  TAKEOFF MINIMUMS  AND (OBSTACLE) 
  DEPARTURE PROCEDURES
  11013
  Diverse departure not authorized.
  Use published  departure procedures 
  for obstacle avoidance. 


Sometimes there is a reminder that it can be used:


  CANNON AFB (KCVS), CLOVIS, NM
  TAKEOFF MINIMUMS  AND (OBSTACLE)
  DEPARTURE PROCEDURES
  ORIG 15064
  Diverse departure authorized all runways.
  


This default procedure is valid only when:


Not explicitly prohibited,
There is at least one instrument approach for the airport
No obstacle departure procedure (ODP) and
No standard departure (SID) has been published for the airport.


A diverse departure is conducted this way:


Cross the runway end at 35 ft, maintain heading and a 200 ft/NM gradient until 400 ft above the runway end. The 200 ft/NM gradient is TERPS' minimum climb gradient, and corresponds to ICAO's 3.3% for the minimum procedure design gradient.
Continue or turn in any direction while maintaining a minimum rate of climb of 200 ft/NM.
Maintain this rate of climb until reaching a 1,000 ft obstacle clearance or a 2,000ft obstacle clearance in mountainous areas.



Source

The 40:1 ratio (152 ft/NM) delimits a surface from the runway end, named the obstacle clearance surface (OCS). The diverse departure ensures being above the OCS until enroute.

Whenever the conditions exist for a diverse departure, it is implicit ATC authorities have assessed the absence of obstacle above the OCS. This assessment is named the diverse departure assessment.

Given the 40:1 slope and obstacle clearances, the area assessed may have a radius from 25 to 46 NM.