Gravity forward models for a buried line and strip
For an infinite line parallel to y at horizontal coordinate x₀ and depth b>0 with signed excess mass per lengthm_l, its downward surface anomaly is Δg=2Gm_lb/[(x−x₀)²+b²].
Key knowledge
For an infinite line parallel to y at horizontal coordinate x₀ and depth b>0 with signed excess mass per lengthm_l, its downward surface anomaly is Δg=2Gm_lb/[(x−x₀)²+b²]. Integrating lines from x₁ to x₂ gives a thin strip model Δg=2GΔρH[arctan((x₂−x)/b)−arctan((x₁−x)/b)]. Greater burial broadens a fixed line-mass anomaly and lowers its peak magnitude.
Values and equations
Δg_line=2Gm_lb/[(x−x₀)²+b²]; Δg_strip=2GΔρH[arctan((x₂−x)/b)−arctan((x₁−x)/b)]
- Δg_line,Δg_strip
- downward surface gravity anomalies m s⁻²
- m_l
- signed excess mass per line length kg m⁻¹
- Δρ
- density contrast kg m⁻³
- x,x₀,x₁,x₂,b,H
- surface coordinate, source coordinates, depth and thin thickness m
- G
- Newtonian gravitational constant m³ kg⁻¹ s⁻²
Conditions and scope
- Local Cartesian gravity model, observer at z=0, line/strip at z=−b, uniform infinite y extent. The thin strip places all excess mass of cross-sectional thicknessH at one depth, requiring thickness small compared with relevant depth/geometric scales.
- A finite-length/3D body, variable depth, terrain or broader thickness needs a volume integral. Δρ is contrast, not absolute density. Resolving a broad source from a line also depends on sampling/noise; good fitting within this family does not prove its unique geological origin.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Read actual printed57–59 Newtonian volume-element vertical component, infinite-line integral, strip arctangent and line-versus-strip resolution discussion. Rechecked by integrating b/[(x−x₀)²+y²+b²]^(3/2) over y and then x₀; stated thin-depth and infinite-length bounds instead of claiming the sheet reduction general.
2026-10-10 · Independent AI editorial review: All73 exact supplement compact statements, conditions, displayed equations and247 origin semantic links read; all109 combined original36+supplement73 author-source rows, exact locators, hypotheses, exclusions and disclosed derivations assessed. Original36 exact scientific content is independently approved in the linked receipt. All18 inherited Earth compact references and shared Math/Physics/Measurement methods were considered in the full practical Earth inventory. Targeted actual primary sections listed below; not every source body/proof or every possible university elective independently reread. AI editorial reference review, not human certification, full-degree proficiency, new experimental validation or a claim of whole combined Earth-and-Cosmos approval. Receipt: earth-completion-independent-content-inventory-review.1.
Entry details
Permanent link to this entry ↗- Record identity
- uni-earth-gravity-line-strip
- Revision
- core.1
- Structured reference record
- University core expansion