[PHI 3000] Metaphysical foundationalism

Jonathan Schaffer has put forward the notion of metaphysical foundationalism:

the metaphysical foundationalist thinks all being must originate in basic being and rejects limitless chains of dependence (metaphysical infinitism) and circular dependence (metaphysical coherentism). There must be a ground of being. If one thing exists only in virtue of another, then there must be something from which the reality of the derivative entities ultimately derives.

There seem to be two major claims here:

1. "There must be a ground of being."
2. "If one thing exists only in virtue of another, then there must be something from which the reality of the derivative entities ultimately derives."

Both (1) and (2) are supposed to be laws of metaphysics, i.e., true in every possible world. 

Now, consider a possible world in which there is nothing but one quark (or string or whatever else the basic constituent of matter turns out to be). Is this a possible world where being has no ground?

Also, consider a possible world that consists of Leibnizian monads "all the way down." Is this a possible world in which there is no ultimate reality from which the reality of the monads is derived?