Peccia, A., Moussallam, Y., Plank, T., DallaSanta, K., Polvani, L., Burgisser, A., Larsen, J., and Schaefer, J., 2023, A new multi-method assessment of stratospheric sulfur load from the Okmok II caldera-forming eruption of 43 BCE: Geophysical Research Letters v. 50, no. 21, e2023GL103334. https://doi.org/10.1029/2023GL103334.
http://dx.doi.org/10.1029/2023GL103334

Larsen, J.F., Schaefer, J.R., and Cameron, C.E., 2022, Electron probe microanalytical data of minerals and glass from rock samples from Okmok volcano, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File 2022-6, 13 p. https://doi.org/10.14509/30853.
http://dx.doi.org/10.14509/30853
publication on DGGS website

Schaefer, J.R.G., Perreault, J.M., Larsen, J.F., and Vallance, J.W., 2020, Makushin Volcano ash hazards: Alaska Division of Geological & Geophysical Surveys Information Circular 86, 2 p., http://doi.org/10.14509/30411.
http://dx.doi.org/10.14509/30411
reference on DGGS website

Cameron, C.E., Schaefer, J.R., and Ekberg, P.G., 2020, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 4, 2 sheets. Http://doi.org/10.14509/30426
http://dx.doi.org/10.14509/30426
download publication from ADGGS website

Bergfeld, Deborah, Evans, W.C., Hunt, A.G., Lopez, Taryn, and Schaefer, J.R., 2020, A post-eruption study of gases and thermal waters at Okmok volcano, Alaska: Journal of Volcanology and Geothermal Research, v, 396, doi:10.1016/j.jvolgeores.2020.106853.
http://dx.doi.org/10.1016/j.jvolgeores.2020.106853
article on JVGR website

McConnell, J.R., Sigl, Michael, Plunkett, Gil, Burke, Andrea, Kim, W.M., Raible, C.C., Wilson, A.I., Manning, J.G., Ludlow, Francis, Chellman, N.J., Innes, H.M., Yang, Zhen, Larsen, J.F., Schaefer, J.R., Kipfstuhl, Sepp, Mojtabavi, Seyedhamidreza, Wilhelms, Frank, Opel, Thomas, Meyer, Hanno, and Steffensen, J.P., 2020, Extreme climate after massive eruption of Alaska's Okmok volcano in 43 BCE and effects on the late Roman Republic and Ptolemaic Kingdom: Proceedings of the National Academy of Science of the United States of America, 7 p., www.pnas.org/cgi/doi/10.1073/pnas.2002722117.
http://dx.doi.org/10.1073/pnas.2002722117
article on PNAS website

Larsen, J.F., Schaefer, Janet, Vallance, J.W., and Neill, O.K., 2020, Petrology and geochemistry of three Early Holocene eruptions from Makushin Volcano, Alaska: Bulletin of Volcanology, v. 82, n. 72, 17 p., doi:10.1007/s00445-020-01412-5.
http://dx.doi.org/10.1007/s00445-020-01412-5

Cameron, C.E., Mulliken, K.M., Crass, S.W., Schaefer, J.R., and Wallace, K.L., 2019, Alaska Volcano Observatory geochemical database, version 2: Alaska Division of Geological & Geophysical Surveys Digital Data Series 8 v. 2, 22 p., https://www.avo.alaska.edu/geochem/. Http://doi.org/10.14509/30058
http://dx.doi.org/10.14509/30058
application on AVO page
citation on DGGS page

Coombs, M.L., Wech, A.G., Haney, M.M., Lyons, J.J., Schneider, D.J., Schwaiger, H.F., Wallace, K.L., Fee, David, Freymueller, J.T., Schaefer, J.R., and Tepp, Gabrielle, 2018, Short-term forecasting and detection of explosions during the 2016-2017 eruption of Bogoslof Volcano, Alaska: Frontiers in Earth Science, v. 6, article 122, doi: 10.3389/feart.2018.00122 .
http://dx.doi.org/10.3389/feart.2018.00122
open-access on publisher website

Worden, A.K., Schaefer, J.R., and Mulliken, K.M., 2018, Tephra occurrence in Alaska: a map-based compilation of stratigraphic tephra data: Alaska Division of Geological and Geophysical Surveys Miscellaneous Publication 165, 19 p., http://doi.org/10.14509/30059
http://dx.doi.org/10.14509/30059
publication for download on DGGS website

Cameron, C.E., Schaefer, J.R., and Mulliken, K.M., 2018, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 3, 2 sheets. Http://doi.org/10.14509/30142
http://dx.doi.org/10.14509/30142
download from DGGS website

Mulliken, K.M., Schaefer, J.R., and Cameron, C.E., 2018, Geospatial distribution of tephra fall in Alaska: a geodatabase compilation of published tephra fall occurrences from the Pleistocene to the present: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 164, 46 p. http://doi.org/10.14509/29847
Link to DGGS publication page

Schaefer, J.R., Scott, W.E., and Layer, P.W., 2017, Geologic map of Mount Chiginagak volcano, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2017-10, 32 p., 1 sheet, scale 1:25,000. http://doi.org/10.14509/29769
http://dx.doi.org/10.14509/29769
Citation page and downloads on DGGS website

Cameron, C.E., Dixon, J.P., Neal, C.A., Waythomas, C.F., Schaefer, J.R., and McGimsey, R.G., 2017, 2014 Volcanic activity in Alaska - Summary of events and response of the Alaska Volcano Observatory: U.S. Geological Survey Scientific Investigations Report 2017-5077, 81 p., https://doi.org/10.3133/sir20175077.
full-text PDF : 6.8 MB

Unema, J.A., Ort, M.H., Larsen, J.F., Neal, C.A., and Schaefer, J.R., 2016, Water-magma interaction and plume processes in the 2008 Okmok eruption, Alaska: GSA Bulletin, 15 p., doi:10.1130/B31360.1
http://dx.doi.org/10.1130/B31360.1

Cameron, C.E., and Schaefer, J.R., 2016, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 2, 1 sheet, scale 1:3,000,000. http://doi.org/10.14509/20181
http://dx.doi.org/10.14509/20181
publication on ADGGS website

Larsen, J.F., Neal, C.A., Schaefer, J.R., Kaufman, A.M., and Lu, Zhong, 2015, The 2008 phreatomagmatic eruption of Okmok Volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2015-2, 53 p. doi:10.14509/29405
http://dx.doi.org/10.14509/29405
link to PDF on DGGS website

Evans, W.C., Bergfeld, D., Neal, C.A., McGimsey, R.G., Werner, C.A., Waythomas, C.F., Lewicki, J.L., Lopez, T., Mangan, M.T., Miller, T.P., Diefenbach, A., Schaefer, J., Coombs, M.L., Wang, B., Nicolaysen, K., Izbekov, P., Maharrey, Z., Huebner, M., Hunt, A.G., Fitzpatrick, J., and Freeburg, G., 2015, Aleutian Arc geothermal fluids: chemical analyses of waters and gases: U.S. Geological Survey Data release, http://dx.doi.org/10.5066/F74X55VB
http://dx.doi.org/10.5066/F74X55VB
data tables (.xlsx) : 101 KB
text and figures to accompany data release, originally hosted on USGS water resources website : 1.9 MB

Schaefer, J.R., Cameron, C.E., and Nye, C.J., 2014, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 1.2, 1 sheet, scale 1:3,000,000. This publication has been superseded. Newest version available at http://www.dggs.alaska.gov/pubs/id/20181 .
PDF files on DGGS's web site

Stelling, P.L., Beget, J.E., Gardner, J.E., and Schaefer, J.R., 2014, Preliminary volcano-hazard assessment for Fisher volcano, Unimak Island, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2014-5, 32 p., 1 sheet, scale 1:500,000. doi:10.14509/29146 .
http://dx.doi.org/10.14509/29146
link to PDF and associated files on DGGS website
full-text PDF : 25 MB
map sheet : 79 MB

Schaefer, J.R., Scott, W.E., Evans, W.C., Wang, Bronwen, and McGimsey, R.G., 2013, Summit crater lake observations, and the location, chemistry, and pH of water samples near Mount Chiginagak volcano, Alaska: 2004-2012: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2011-6 v. 2, 25 p., available online at www.dggs.gov/pubs/id/25602 .
link to publication on ADGGS website

Wallace, K.L., Schaefer, J.R., and Coombs, M.L., 2013, Character, mass, distribution, and origin of tephra-fall deposits from the 2009 eruption of Redoubt Volcano, Alaska - Highlighting the significance of particle aggregation: Journal of Volcanology and Geothermal Research, v. 259, p. 145-169, doi:10.1016/j.jvolgeores.2012.09.015
http://dx.doi.org/10.1016/j.jvolgeores.2012.09.015
full-text pdf : 6.3 MB

Mastin, L.G., Schwaiger, Hans, Schneider, D.J., Wallace, K.L., Schaefer, Janet, and Denlinger, R.P., 2013, Injection, transport, and deposition of tephra during event 5 at Redoubt Volcano, 23 March, 2009: Journal of Volcanology and Geothermal Research, v. 259, p. 201-213, doi:10.1016/j.jvolgeores.2012.04.025
http://dx.doi.org/10.1016/j.jvolgeores.2012.04.025
full-text pdf : 5.6 MB

Larsen, J.F., Sliwinski, M.G., Nye, Christopher, Cameron, Cheryl, and Schaefer, J.R., 2013, The 2008 eruption of Okmok Volcano, Alaska: Petrological and geochemical constraints on the subsurface magma plumbing system: Journal of Volcanology and Geothermal Research, v. 264, p. 85-106, doi:10.1016/j.jvolgeores.2013.07.003 .
http://dx.doi.org/10.1016/j.jvolgeores.2013.07.003

Schaefer, J.R., and Wallace, K.L., 2012, Ash fall contour map of the 2009 eruption of Redoubt Volcano, Alaska: Digital shapefiles of contours and sample locations: Alaska Division of Geological and Geophysical Surveys Miscellaneous Publication 143, 1 DVD. Available free online at http://www.dggs.alaska.gov/pubs/id/23463 .
link to download of publication on DGGS website

Schaefer, J.R., ed., 2012, The 2009 eruption of Redoubt Volcano, Alaska, with contributions by Bull, Katharine, Cameron, Cheryl, Coombs, Michelle, Diefenbach, Angie, Lopez, Taryn, McNutt, Steve, Neal, Christina, Payne, Allison, Power, John, Schneider, Dave, Scott, William, Snedigar, Seth, Thompson, Glenn, Wallace, Kristi, Waythomas, Chris, Webley, Peter, and Werner, Cynthia: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2011-5, 45 p., available at http://www.dggs.alaska.gov/pubs/id/23123.
link to PDF on ADGGS website

Schaefer, J.R., Larsen, J.F., and Unema, J.A., 2011, Digital elevation model (DEM) and shaded relief image of Okmok Caldera, 2010: Alaska Division of Geological & Geophysical Surveys Raw Data File 2011-6, 1 DVD, available online at http://www.dggs.dnr.state.ak.us/pubs/id/23223 .
link to ADGGS website with GIS files for download

Jensen, B.J.L., Preece, S.J., Lamothe, Michel, Pearce, N.J.G., Froese, D.G., Westgate, J.A., Schaefer, Janet, and Beget, Jim, 2011, The variegated (VT) tephra: A new regional marker for middle to late marine isotope stage 5 across Yukon and Alaska: Quaternary International, v. 246, p. 312-323, doi: 10.1016/j.quaint.2011.06.028.
http://dx.doi.org/10.1016/j.quaint.2011.06.028

Neal, C.A., Larsen, J.F., and Schaefer, Janet, 2009, The July-August 2008 hydrovolcanic eruption of Okmok Volcano, Umnak Island, Alaska: Alaska Geological Society Newsletter, v. 39, n. 5, p. 1-3.

Larsen, J., Neal, C., Webley, P., Freymueller, J., Haney, M., McNutt, S., Schneider, D., Prejean, S., Schaefer, J., and Wessels, R., 2009, Eruption of Alaska volcano breaks historic pattern: Eos, Transactions, American Geophysical Union, v. 90, n. 20, p. 173-174.

Schaefer, J.R., and Nye, Chris, 2008, The Alaska Volcano Observatory - 20 years of volcano research, monitoring, and eruption response: Alaska Division of Geological & Geophysical Surveys, Alaska GeoSurvey News, NL 2008-001, v. 11, n. 1, p. 1-9, available at http://wwwdggs.dnr.state.ak.us/pubs/pubs?reqtype=citation&ID=16061 .
ADGGS website with link to PDF
full-text PDF on AVO's server : 5.68 MB

Schaefer, J.R., Wallace, K.L., and Kassel, C.M., 2008, Preliminary bathymetric map of Mother Goose Lake, Alaska Peninsula: Alaska Division of Geological & Geophysical Surveys Raw Data File 2008-3, 1 disc, available at http://www.dggs.dnr.state.ak.us/pubs/id/16301 .
DGGS site with links to data, GIS, and metadata files

Schaefer, J. R., W. E. Scott, W. C. Evans, J. Jorgenson, R. G. McGimsey, and B. Wang, 2008, The 2005 catastrophic acid crater lake drainage, lahar, and acidic aerosol formation at Mount Chiginagak volcano, Alaska, USA: Field observations and preliminary water and vegetation chemistry results: Geochemistry Geophysics Geosystems, v. 9, n. 7, 29 p., Q07018, doi:10.1029/2007GC001900.
http://dx.doi.org/10.1029/2007GC001900

Pfeffer, Melissa, and Schaefer, Janet, 2008, A phytotoxic dense gas flow produced during the crater lake breakout at Chiginagak Volcano, Alaska [abs.]: 33rd International Geological Congress, Oslo, Norway.

Larsen, J. F., Neal, Christina, Schaefer, Janet, Beget, Jim, and Nye, Chris, 2007, Late Pleistocene and Holocene caldera-forming eruptions of Okmok Caldera, Aleutian Islands, Alaska, in Eichelberger, John, Gordeev, Evgenii, Izbekov, Pavel, Kasahara, Minoru, and Lees, Jonathan, eds., Volcanism and Subduction: The Kamchatka Region: Geophysical Monograph 172, American Geophysical Union, p. 343-364.

Ramsey, D. W., Robinson, J. E., Schilling, S. P., Schaefer, J. R., and Trusdell, F. A., 2007, Crisis GIS: Preparing for and responding to volcanic eruptions in the United States, in Thomas, C., ed., Standards for Success: GIS for Federal Progress and Accountability: Redlands, California, ESRI Press, p. 3-8.

Schaefer, J.R., Scott, W.E., McGimsey, R.G., and Jorgenson, Janet, 2006, The 2005 crater lake formation, lahar, acidic flood, and caustic aerosol and gas release from Chiginagak Volcano, Alaska [abs.]: Geological Society of America - Abstracts with Programs, v. 38, n. 5, p. 29.

Schaefer, J. R., 2005, 30-meter shaded relief image of Okmok Volcano, Umnak Island, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File RDF 2005-01, 1 CD-ROM.
MapInfo .TAB file : 1 KB
.TFW file : 1 KB
TIFF image file : 17.4 MB
image of shaded relief TIFF file : 26 KB
metadata for RDF 2005-01 : 23 KB

Beget, J.E., Larsen, J.F., Neal, C.A., Nye, C.J., and Schaefer, J.R., 2005, Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2004-3, 32 p., 1 sheet, scale 1:150,000.
full text of report : 3.4 MB
map sheet : 53.2 MB
link to all files for this report on DGGS website

Schaefer, J.R., Scott, W.E., McGimsey, R.G., Jorgenson, Janet, 2005, The 2005 crater lake formation, lahar, acidic flood, and gas emission from Chiginagak volcano, Alaska, [abs.]: EOS, Transactions of the American Geophysical Union Fall Meeting Supplement, Abstract V21E-0675.

Schaefer, Janet, and Nye, C. J., 2002, Historically active volcanoes of the Aleutian Arc: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication MP 0123, unpaged, 1 sheet, scale 1:3,000,000. Superceded by Miscellaneous Publication 133: http://www.dggs.dnr.state.ak.us/pubs/pubs?reqtype=citation&ID=20181
link to PDF files on DGGS website of MP133, which updates MP123

Nye, C. J., Keith, T. E. C., Eichelberger, J. C., Miller, T. P., McNutt, S. R., Moran, S., Schneider, D. J., Dehn, J., and Schaefer, J. R., 2002, The 1999 eruption of Shishaldin Volcano, Alaska: monitoring a distant eruption: Bulletin of Volcanology, v. 64, n. 8, p. 507-519.
http://dx.doi.org/10.1007/s00445-002-0225-2

Beget, J. E., Nye, C. J., Schaefer, J. R., and Stelling, P. L., 2002, Preliminary volcano-hazard assessment for Shishaldin Volcano, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2002-4, 28 p., 1 sheet, scale 1:500,000.
full-text PDF : 2.25 MB

Schaefer, J. R. G., 2002, Stratigraphy, major oxide geochemistry, and 40Ar/39Ar geochronology of a tephra section near Tok, Alaska: University of Alaska Fairbanks unpublished M.S. thesis, 62 p.
full-text PDF : 2.06 MB

Schaefer, J. R. G., Layer, P. W., Beget, J. E., and Drake, Jeff, 2000, (super 40) Ar/ (super 39) Ar dating of Quaternary low-potassium hornblende from a fine-grained Alaskan tephra by total laser-fusion [abs.]: Eos, v. 81, n. 48, p. 1375-1376.