Okay, so let's review the scene, but before we do, we have to go back a little in the movie, a few hours earlier, when the tour starts and finally the group comes to the T-Rex paddock. After the big animal doesn't show up (which is a great moment because the whole audience cranes their necks to see the T-Rex just like the cast does) they try to entice it to come out by "offering up" a goat. Note goat. He's just standing there. This will be important later.
The film makers needed to get Alan and the kids out of the way so they couldn't be found when Ellie and Muldoon come back to find Ian. So the sudden insertion of a cliff becomes totally necessary to move the story along and very few people even noticed due to all the action and the duration of the T-Rex attack. So, is this sort of continuity bad? Not at all. Sometimes the story needs a push, and if the audience as a whole doesn't notice, then do it! If you need place a light source in a weird place in your illustration or film so the action is easier to read, do it. If you need to do something out of the ordinary or even beyond the limits of reality to boost your story, and you can get away with it, do it. Maybe in 20 years somebody will write a blog post about that decision. If you are able to keep the audience focused on what you want them too, you can get away with almost anything. Don't believe me? Check out this link and be amazed. Go to this IMDB link for more info about Jurassic Park. If you'd like to see a complete set of storyboards from the film, I recommend this book. Now go back and watch this film. I also love the kitchen scene but can't help rooting for any and all of the dinosaurs, especially when it comes to eating those annoying kids. Thanks for stopping by.