What can GPR detect?

Ground-penetrating radar sends radio-wave pulses into the ground and records the reflections that come back. Changes below the surface — disturbed or refilled soil, voids, buried objects, differences in soil density and moisture — reflect the signal differently than undisturbed ground. Grave shafts, because they were dug and refilled, often produce recognizable patterns of disturbance at consistent depths, especially when several appear in rows or regular spacing.

What can’t GPR prove?

GPR does not produce pictures of what lies underground, and it cannot identify remains, read names, or confirm who is buried where. It shows anomalies — places where the ground responds differently. Interpretation connects those anomalies to the historical record; the radar alone never does.

So an anomaly means a grave?

No — and this matters. Anomalies do not automatically prove graves. Tree roots, rodent burrows, old fence posts, buried debris, utility lines, natural soil variation, and past digging of every kind can all produce anomalies. A grave-like anomaly becomes evidence of a grave only when the pattern, depth, spacing, and historical record all point the same way — and even then it is a strong indication, not proof.

What affects the results?

A great deal. Soil type and moisture, terrain, vegetation, access, obstacles, and the size of the search area all affect what GPR can resolve. Clay soils absorb signal; rocky ground scatters it; recent rain changes readings. The same unit that produces clean data in a sandy churchyard may struggle in a wet clay bottomland.

How long does a survey take?

Longer than most people expect. GPR fieldwork is time-intensive: the unit moves at a walking pace along a tight grid of passes. A scan area of roughly 50 yards by 20 yards can take a full day, depending on terrain, vegetation, obstacles, ground conditions, and the level of detail required. The smaller and more precisely defined the suspected area, the more practical it is to evaluate.

What does the site need to look like for a survey to work?

Our current GPR unit is wheeled and must remain in contact with the ground. A useful rule of thumb:

“If you could push a push mower through the area at its lowest setting without major obstructions, we may be able to survey it effectively.”

High undergrowth, fallen trees, fencing, dense grave markers, brick or walled plots, steep terrain, and other obstructions can limit or prevent a survey. When you submit a tip, one overall photo of the area helps us assess this quickly.

Do you dig to confirm what the radar shows?

Never. Just Beyond the Grave does not excavate and does not disturb graves. Our work is non-invasive documentation and preservation. Where confirmation beyond radar is warranted, that is a matter for the appropriate professional and legal authorities, with the landowner’s and community’s involvement.

Can you survey any property?

Only with lawful access. We require permission from the property owner or the responsible organization before any fieldwork, and we respect tribal, cemetery-board, community, and family concerns about a site.

If I submit a site, will you survey it?

Every project is evaluated individually. Submission does not guarantee acceptance, scheduling, filming, publication, or investigation. Evidence quality, access, terrain, travel logistics, and mission fit all factor in — and tips are often grouped by region so a single trip can serve several sites.