Trona, California

The same ground, surveyed 78 years apart. Drag the handle to wipe between them. Both sheets are United States Geological Survey originals; neither has been altered.

1915 1993

Matched by testing this settlement's coordinate against the published boundary of every sheet in the United States Geological Survey's historical collection. Each opens the scanned sheet at the Survey.

• 1915 USGS Searles Lake quadrangle1:250000, 6 printings
• 1947 USGS Trona quadrangle1:250000
• 1948 USGS Trona quadrangle1:250000
• 1949 USGS Trona quadrangle1:62500, 4 printings
• 1950 USGS Trona quadrangle1:62500
• 1953 USGS Trona quadrangle1:250000
• 1957 USGS Trona quadrangle1:250000, 5 printings
• 1960 USGS Trona quadrangle1:250000, 2 printings
• 1982 USGS Trona East quadrangle1:24000
• 1993 USGS Ridgecrest quadrangle1:100000, 2 printings

Regional context, not property-specific evidence. The federal wildfire occurrence database lists 16 fires within 5 miles of Trona between 1995 and 2020, burning about 309 acres in total. None started naturally. None was recorded as arson. Distance is straight-line from the map coordinates, so a fire counted here may appear on a neighbouring settlement's page as well.

The most recent of them, most recent first, with the day each was reported and the service that recorded it.

Settlements close enough to share some of these fires:

• Pioneer Point
• Argus
• Borosolvay
• Searles Valley
• South Trona
• Westend

Every fire recorded in San Bernardino County

Regional context, not property-specific evidence. The federal mineral resources record lists 18 workings within 5 miles of Trona: 6 producers, 5 occurrences, 5 past producers, 1 unknown. 7 still produce. What was taken out: Salt, Gold, Boron-Borates, Sand and Gravel, Construction. Distance is straight-line from the map coordinates, so a quarry counted here may appear on a neighbouring settlement's page as well.

Every working recorded in San Bernardino County

The eight closest, with where each one stands in the county. Distances are straight-line, computed from the Geographic Names Information System coordinates.

Matched on this settlement's Geographic Names Information System number rather than its name, so it cannot be a different place of the same name in another state.

This settlement is recorded in the Geographic Names Information System as feature 250630. The sheet list is computed by point-in-boundary test against the United States Geological Survey's historical topographic inventory. Both are works of the United States government and carry no copyright under 17 U.S.C. 105.

Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.

Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.