Usually, the penalties for causing collisions vary depending on the severity of the crash. Most common penalties seen nowadays are grid penalties for the following race and 10-second time penalties.
Let's take Monaco 2016 for example, as the race offered both kinds of penalties.
A couple examples of accidents that caused grid penalties are Daniil Kvyat and Marcus Ericsson.
- Kvyat lunged into Kevin Magnussen's Renault into Rascasse and sent
both cars into the wall, which brought out double yellow flags in the
- Ericsson did the same move Kvyat did, but on his Sauber teammate Felipe Nasr, with equal results. This actually resulted in both Saubers scoring a DNF.
Valtteri Bottas and Pascal Wehrlein were given 10-second time penalties added to their overall race times, but for completely different reasons.
- On the final lap again at Rascasse, Bottas made a move on the inside of Esteban Gutierrez's Haas, pushing him off line and nearly into the wall, but while none of the cars were damaged, Bottas' move was aggressive enough to cause unnecessary contact.
- Pascal Wehrlein meanwhile, was actually given two separate 10-second time penalties. First was for ignoring blue flags, and the other for lapping too quickly during the Virtual Safety Car period.
In the case of the Rosberg-Hamilton crash in Austria, Rosberg was found to be the aggressor, but because he came out the worst in that accident, and Hamilton did not go off the track and lose several positions nor sustained significant damage, the penalty was not too severe.
In the F1 website, they actually stated that the stewards have the power to give tougher penalties for "extreme cases", which includes the grid penalties.
Edit: A more specific entry on the regulations and on the applications of penalties from the FIA Formula One World Championship Regulations
38) INCIDENTS DURING THE RACE
38.1 "Incident" means any occurrence or series of occurrences involving one or more drivers, or any action by any driver, which is reported to the stewards by the race director (or noted by the stewards and subsequently investigated) which :
d) Caused a collision.
38.3 The stewards may impose any one of the penalties below on any driver involved in an Incident:
b) A ten second time penalty. The driver must enter the pit lane, stop in his pit stop position for at least ten seconds and then re-join the race. The relevant driver may however elect not to stop, provided he carries out no further pit stop before the end of the race. In such cases ten seconds will be added to the elapsed race time of the driver concerned.
g) A drop of any number of grid positions at the driver’s next Event.