In parts of Connecticut and Massachusetts, foundations of some homes are cracking and crumbling. Failing foundations can reduce the market value of a home and lifting a house to replace and repour a foundation is an expensive undertaking. In response, some homeowners are defaulting on their mortgages and abandoning their homes. The culprit is pyrrhotite, which occurs in construction aggregate (crushed stone) that was used as a filler in concrete. When pyrrhotite is naturally exposed to water and oxygen, it breaks down to produce sulfuric acid and secondary minerals, including gypsum, which have larger volumes than the pyrrhotite they replace. The expanded volume of the secondary minerals cracks and degrades concrete.
Mauk, J.L., Crafford, T.C., Horton, J.D., San Juan, C.A., and Robinson, G.R., Jr., 2020, Pyrrhotite distribution in the conterminous United States, 2020: U.S. Geological Survey Fact Sheet 2020-3017, 4 p., https://doi.org/10.3133/fs20203017.
ISSN: 2327-6932 (online)
ISSN: 2327-6916 (print)
|Publication Subtype||USGS Numbered Series|
|Title||Pyrrhotite distribution in the conterminous United States, 2020|
|Series title||Fact Sheet|
|Publisher||U.S. Geological Survey|
|Publisher location||Reston VA|
|Contributing office(s)||Central Mineral and Environmental Resources Science Center|
|Description||Report: 3 p.; Data Release|
|Other Geospatial||Conterminous United States|
|Online Only (Y/N)||N|
|Google Analytic Metrics||Metrics page|