Question

is there a sentence fragment? lava from the hawaiian volcano kilauea usually flows southward into the ocean. in june of 2014, though, northward.

Explanation:

A sentence fragment lacks a subject, verb, or a complete thought. The given text "Lava from the Hawaiian volcano Kilauea usually flows southward into the ocean. In June of 2014, though, northward." is a complete - thought sentence with a subject (lava from Kilauea) and verb (flows), and the additional information in June 2014 is also part of the complete thought.

Answer:

no