AA-2026-0D4E9F
On the image
Someone laid a rock hammer across a bedding plane and walked away satisfied, because in the 1960s that was how a geologist signed a photograph. No ruler, no card, no name tag – just the one tool every field scientist already owned, dropped into frame to tell a future viewer how big the crack in the rock actually is.
The layered sandstone underneath has been doing its slow work for millions of years, laying down bands one flood or one season at a time, utterly indifferent to the fact that a person with a notebook has just decided it deserves a photograph. The fracture running through it will get a name in someone's field report, a formation, a fault, a bedding contact, and then get filed away with a hundred nearly identical slides.
The hammer, meanwhile, remains the real hero of the picture, having been swung at outcrops from one end of a survey area to the other and asked to pose as a ruler each time. It never once complained about the job being beneath it.
The historian's note
This is a standard field-geology reference photograph from the 1960s, a period when systematic bedrock and stratigraphic surveys were expanding across North America and elsewhere, often tied to petroleum exploration, highway cuts, and academic mapping projects. The rock hammer placed in the frame is a conventional scale device, used in the absence of a graduated scale bar or measuring tape, a common field practice of the era before standardised photographic scales became routine in published geology.
The subject appears to be a sedimentary rock face, likely sandstone or a related clastic unit, showing visible bedding planes and a fracture or joint running through the strata. Such photographs were typically taken to document outcrop character, structural features, or stratigraphic sequence for inclusion in a field notebook, thesis, or survey report.
The strong colour cast visible in the image is consistent with the ageing of period colour transparency materials rather than any feature of the rock itself.
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Visually related — by likeness
Rock Hammer for Scale, Field Geology Survey, 1960s. 1960–1969. Archive & Atlas, Historical Image Library, AA-2026-0D4E9F. https://thearchive.archiveandatlas.com/library/rock-hammer-for-scale-field-geology-survey-1960s.
@misc{aaAA20260D4E9F,
title = {Rock Hammer for Scale, Field Geology Survey, 1960s},
year = {1960–1969},
howpublished = {Archive \& Atlas, Historical Image Library},
note = {Accession AA-2026-0D4E9F},
url = {https://thearchive.archiveandatlas.com/library/rock-hammer-for-scale-field-geology-survey-1960s}
}TY - ART TI - Rock Hammer for Scale, Field Geology Survey, 1960s PY - 1960–1969 PB - Archive & Atlas, Historical Image Library AN - AA-2026-0D4E9F UR - https://thearchive.archiveandatlas.com/library/rock-hammer-for-scale-field-geology-survey-1960s ER -
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