The Hawaiian Volcano Observatory (HVO) Bulletin series was an informal publication issued between the years 1913 to 1929. Individual issues contain information on volcanic and earthquake activity, volcano research, and volcano monitoring in Hawaii, and issues often included photographs, sketches, and data plots. Information on volcanic activity at other locations is also occasionally included.
The Bulletin series was published by HVO through the Hawaiian Volcano Research Association. Weekly Bulletins (initially called Reports) were issued between June 28, 1913, and July 1, 1914. Bulletins were issued monthly after July 1, 1914, though they were still named Weekly Bulletins until January 1919. Starting with the February 1919 issue, the Bulletins were named Monthly Bulletins, and they continued to be issued monthly until the series ceased in July 1929. During a single year, 1915, Seismometric Bulletins were also issued quarterly. These four issues contain summaries of seismic observations recorded by the then-nascent Whitney Laboratory of Seismology, located underground in a vault near the summit of Kīlauea.
Two of the bulletins are misnumbered:
• April 1916 volume IV no. 4 incorrectly says April 1915 volume III no. 4
• September 1916 volume IV no. 9 incorrectly says September 1916 volume VI no. 9
