that's a "comma + abstract noun" setup. it probably has some sort of grammatical name, but i have absolutely no idea what that name is.
--
COMMA + ABSTRACT NOUN is allowed to stand for the ENTIRE IDEA OF THE PRECEDING CLAUSE.
examples:
the coach tried to put 5 receivers on the line, a strategy that failed.
--> here, "a strategy" (an ABSTRACT noun) stands for the WHOLE IDEA of putting 5 receivers on the line.
X observed large concentrations of metals in the sediments, findings consistent with...
in this case, "findings" (an abstract noun) stands for the WHOLE IDEA of observing large concentrations of blah blah blah.
etc.
on the other hand,
COMMA + CONCRETE NOUN usually stands for the DIRECTLY PRECEDING NOUN.
compare:
i went to the bar with john smith, a consultant in los angeles.here, "a consultant" (a CONCRETE noun) refers ONLY to "john smith" (the preceding noun).
i went to the bar with john smith, an excursion that was much more fun than working all night.here, "an excursion" (an ABSTRACT noun) stands for the WHOLE IDEA of going to the bar with john smith.
--
your construction is like the first couple in these examples.
--
COMMA + ABSTRACT NOUN is allowed to stand for the ENTIRE IDEA OF THE PRECEDING CLAUSE.
examples:
the coach tried to put 5 receivers on the line, a strategy that failed.
--> here, "a strategy" (an ABSTRACT noun) stands for the WHOLE IDEA of putting 5 receivers on the line.
X observed large concentrations of metals in the sediments, findings consistent with...
in this case, "findings" (an abstract noun) stands for the WHOLE IDEA of observing large concentrations of blah blah blah.
etc.
on the other hand,
COMMA + CONCRETE NOUN usually stands for the DIRECTLY PRECEDING NOUN.
compare:
i went to the bar with john smith, a consultant in los angeles.here, "a consultant" (a CONCRETE noun) refers ONLY to "john smith" (the preceding noun).
i went to the bar with john smith, an excursion that was much more fun than working all night.here, "an excursion" (an ABSTRACT noun) stands for the WHOLE IDEA of going to the bar with john smith.
--
your construction is like the first couple in these examples.