Does the heroic code expressed in beowulf conflict with a christian sensibility?

In a way, yes it is.
Even though throughout the story Beowulf keep displaying some characteristic that are worthy of praise (his willingness to sacrifice and his capability to be a leader), he also has a character that is despised by the Christian teaching (such as some of his action is based on Vengeance, not the desire to help other)

The lowest elevation is found at the Sea of Galilee lake Nasser because of the Mariana Trench.