State geologist of Michigan. Field notes, 1837-1841, of his geological survey of the state, including some original drawings [original and typescript copies, and microfilm of pages 197-291]; letter book, 1841-1845; miscellaneous correspondence and field notes, including letter, May 31, 1841, to Abram Sager; notes and other papers collected by Mrs. John Ehlers for her book on Houghton, including copies of papers of Bela Hubbard; and photographs.
The Douglass Houghton manuscript collection at the Michigan Historical Collections includes one volume of field notes, 1837-1841; typed transcripts of the field notes; a one volume letterpress book, 1841-1845; miscellaneous correspondence, newspaper clippings and other papers (photostats and typescripts of materials in other repositories); and notes collected by Mrs. John Ehlers for a book on Houghton.
An appendix to this finding aid contains an inventory to the manuscript maps found in the collection, and other Houghton maps.
The reports of Houghton's work for the Michigan Geological Survey have been published in Geological Reports of Douglass Houghton: First State Geologist of Michigan, 1837-1845, Lansing, Mich.: Michigan Historical Commission 1928. [MHC call number EA/153/MG345/G345, available online through HathiTrust]