Question on semantics of reified statements

After posting a example to the Jena e-mail list,
I realized that there is a deeper issue, relating
to the semantics of RDF reified statements, that
I don't know the answer to.  Here is the example:


"John states that (a ship) s1 visited Antwerp
on March, 2003."

"Sue states that s1 visited Antwerp
on April, 2003."

Below is a set of RDF statements intended to represent the above two
sentences.  I'm trying to keep things simple -- I've left out the
assertion that 's1' is a ship, and I'm using an n3-like notation that
omits some namespaces:

st1 rdf:type rdf:Statement.
st1 rdf:subject s1.
st1 rdf:predicate location.
st1 rdf:object antwerp.
st1 beginDate "March 2003".
st1 endDate "March 2003".
st1 author john.

st2 rdf:type rdf:Statement.
st2 rdf:subject s1.
st2 rdf:predicate location.
st2 rdf:object antwerp.
st2 beginDate "April 2003".
st2 endDate "April 2003".
st2 author sue.

My intent is that 'st1' and 'st2' are both reifications of the
same statement   [s1 location antwerp].  My question is, are
st1 and st2 the same resource, or are they two distinct
resources?

Cheers, Bob

P.S., I don't consider the above encoding to be a particularly good
use of RDF reification, but that's not germane to my question
in this posting.