A quick check of Wikipedia informs me that Gilsonite is a trademarked (or not) name for a type of asphalt mined from one spot in Utah. Weird. OK, so removing the trademarked name, you're asking how asphalt bonds with other petroleum products.
There's not much here for us to work with. Asphalt is a mixture. Petroleum, oil, diesel fuel is also a mixture. You say "bond" -- are you asking for one chemical reaction, or several? Given there are dozens of compounds at hand, the problem simply isn't clear enough for a simple answer.