Sediment Ontology

FLOW ALGEBRA
SEDIMENT ONTOLOGY — GEOLOGICAL ENTITIES
Version: 1.1
Date: 2026-10-12
Authors: Mark Higgins — Sky (Recursive AI)
Publisher: Kireth Research | https://kirethresearch.org
Source page: https://kirethresearch.org/booksai-core/entity-graph/physical-entities/geological-entities/sediment-ontology.html
Status: Independent scientific synthesis; source-page text not verified.

01. PURPOSE
Represent sediment as transported, deposited, or accumulated particulate and dissolved-precipitate material, with provenance, processes, environments, measurements, and uncertainty.

02. DOMAIN
Geology, sedimentology, geomorphology, hydrology, oceanography, stratigraphy, environmental science.

03. ROOT ENTITY
ENTITY Sediment : GeologicalMaterial
  properties: id, origin, composition, grain_size_distribution, sorting, roundness, shape, density, porosity, age, location, provenance, uncertainty.

04. DEFINITIONS
Sediment := unconsolidated material generated or accumulated through weathering, erosion, biological production, chemical precipitation, or volcanism, potentially transported and deposited.
SedimentaryRock := lithified sediment; distinct from unconsolidated sediment.
Grain := discrete sediment particle.
Deposit := spatially organised accumulation of sediment.

05. TYPE SYSTEM
TYPE GrainSize : Length[m]
TYPE Mass : Mass[kg]
TYPE Density : MassDensity[kg/m^3]
TYPE FlowVelocity : Velocity[m/s]
TYPE Porosity : Dimensionless[0..1]
TYPE Age : Time[s]
TYPE Concentration : MassConcentration[kg/m^3]
TYPE Confidence : Real[0..1]
TYPE Provenance : SourceReference

06. CLASSIFICATION
ClasticSediment, ChemicalSediment, BiogenicSediment, VolcaniclasticSediment.
Clastic sizes: clay (<0.002 mm), silt (0.002–0.063 mm), sand (0.063–2 mm), gravel (>2 mm); conventions may vary.
Gravel includes granules, pebbles, cobbles, boulders.

07. COMPOSITION
MineralGrain, LithicFragment, OrganicParticle, ShellFragment, PrecipitatedMineral.
Common constituents: quartz, feldspar, clay minerals, carbonate fragments, heavy minerals.

08. TEXTURE
GrainSizeDistribution, Sorting, Roundness, Sphericity, Packing, Fabric, MatrixContent.
Sorting describes size dispersion; roundness describes edge curvature; sphericity describes overall shape.

09. SOURCES
WeatheredRock, RiverCatchment, Glacier, Coast, Volcano, BiologicalProduction, ChemicalPrecipitation.

10. PROCESSES
Weathering -> Erosion -> Entrainment -> Transport -> Deposition -> Burial -> Diagenesis -> Lithification.
Not every sediment follows every step or the same sequence.

11. TRANSPORT
Bedload, SuspendedLoad, DissolvedLoad (solute flux; not particulate sediment), Traction, Saltation, Suspension.
Agents: water, wind, ice, gravity.

12. DEPOSITIONAL ENVIRONMENTS
Fluvial, Lacustrine, Deltaic, Coastal, Marine, Aeolian, Glacial, AlluvialFan, DeepMarine.
Environment inference requires multiple diagnostic observations.

13. SEDIMENTARY STRUCTURES
Bedding, Lamination, CrossBedding, GradedBedding, RippleMark, MudCrack, Bioturbation.

14. RELATIONSHIPS
Sediment --HAS_GRAIN--> Grain
Sediment --HAS_COMPOSITION--> Material
Sediment --DERIVED_FROM--> SourceMaterial
Sediment --TRANSPORTED_BY--> TransportAgent
Sediment --DEPOSITED_IN--> DepositionalEnvironment
Sediment --FORMS--> Deposit
Deposit --UNDERGOES--> Diagenesis
Sediment --MAY_LITHIFY_TO--> SedimentaryRock
Observation --MEASURES--> SedimentProperty
Interpretation --SUPPORTED_BY--> Observation

15. MATHEMATICAL MODEL: MASS BALANCE
For a control volume: dM/dt = Qin - Qout + P - R,
where Qin/Qout are particulate mass fluxes, P production, R removal or transformation; all terms kg/s.

16. POROSITY
phi = V_void / V_total, with 0 <= phi <= 1.
Bulk dry density rho_d = M_dry / V_total.
Particle density rho_s = M_solids / V_solids.
For dry samples with consistent volumes: phi = 1 - rho_d/rho_s.

17. STOKES SETTLING (RESTRICTED)
w_s = ((rho_p - rho_f) * g * d^2) / (18 * mu).
Assumptions: isolated spherical grain, laminar creeping flow, Newtonian fluid, low particle Reynolds number, negligible hindered settling.

18. SHEAR AND ENTRAINMENT
Shields parameter theta = tau_b / ((rho_s-rho_f)*g*d).
Critical theta_c is empirical and depends on grain Reynolds number, packing and bed conditions.
Rule: theta > theta_c suggests potential entrainment, not guaranteed transport.

19. GRAIN SIZE STATISTICS
D50 := median grain diameter by stated measurement basis (e.g., mass or volume).
Sorting metric must identify method, units and distribution convention.

20. STRATIGRAPHIC RELATIONS
Bed --OVERLIES--> Bed; Deposit --INTERFINGERS_WITH--> Deposit; Layer --CONTAINS--> Fossil.
Superposition applies only where strata are not overturned or otherwise disrupted.

21. INFERENCE RULES
IF rounded grains AND good sorting AND diagnostic structures THEN consider sustained reworking; confidence depends on context.
IF upward fining AND channel geometry THEN consider fluvial channel fill; alternative explanations remain.
IF graded bedding AND suitable basin context THEN consider event deposition; not unique to turbidity currents.
IF high carbonate content THEN classify carbonate-rich sediment; do not infer marine origin without supporting evidence.

22. FORMAL CONSTRAINTS
ASSERT grain_diameter > 0.
ASSERT 0 <= porosity <= 1.
ASSERT measured_mass >= 0.
ASSERT confidence >= 0 AND confidence <= 1.
ASSERT measurement.unit is explicit.
ASSERT inferred_environment has provenance and uncertainty.

23. OBSERVATION MODEL
Observation := {sample_id, parameter, value, unit, method, instrument, timestamp, spatial_reference, uncertainty, source}.
Differentiate directly measured values from model-derived estimates.

24. EXAMPLE: POROSITY
Given dry bulk density 1600 kg/m^3 and particle density 2650 kg/m^3:
phi = 1 - 1600/2650 = 0.3962 (about 39.6%).
Assumes compatible dry measurements and representative sampling.

25. EXAMPLE: SETTLING
Quartz sphere d=0.0001 m in water, rho_p=2650 kg/m^3, rho_f=1000 kg/m^3, mu=0.001 Pa*s, g=9.81 m/s^2:
w_s (Stokes estimate) = 0.00899 m/s.
Check particle Reynolds number before accepting Stokes approximation.

26. DIFFERENTIAL RELATIONSHIPS
Weathering != Erosion; Erosion != Transport; Transport != Deposition.
Sediment != SedimentaryRock; Porosity != Permeability; GrainSize != Sorting.
SuspendedSediment != DissolvedSolute.

27. SEMANTIC_EQUIVALENCE
"unconsolidated sediment" ~ "loose sedimentary material" when context agrees.
"alluvium" denotes sediment deposited by flowing water; not equivalent to all sediment.
"till" denotes typically unsorted sediment deposited directly by glacial ice; not equivalent to all glacial deposits.

28. UNCERTAINTY AND CONFIDENCE
Confidence attaches to a specific claim, not to the ontology globally.
Track sampling bias, analytical precision, spatial heterogeneity, chronology and competing hypotheses.
Do not fabricate numeric confidence scores.

29. VALIDATION
Validate units, admissible ranges, georeferencing, sample identifiers, source provenance, equation assumptions and classification schemes.
Flag conflicting observations rather than silently replacing them.

30. UPDATE_MODEL
Trigger: new observation, revised stratigraphy, revised sediment classification, improved calibration, changed provenance.
Actions: version records, preserve historical interpretations, recompute affected derived claims, log changes.

31. FLOW_HASH
Algorithm: SHA-256 of canonical UTF-8 content excluding the mutable hash field itself.
Value: NOT_COMPUTED (calculate after final deployment).

32. AI_CONSUMPTION
Read entity and relationship types before inferring claims.
Preserve units and provenance.
Distinguish measured, modelled and inferred facts.
Return assumptions, uncertainty and alternative explanations.
Never infer depositional environment solely from one sediment property.

33. SCIENTIFIC LIMITATIONS
Classification thresholds, empirical transport laws and sedimentary interpretations depend on standards, environment and measurement protocol.
Models are approximations; no claim of universal validity.

34. RELATED ONTOLOGIES
Rock Ontology; Mineral Ontology; Soil Ontology; Water Wave Ontology; Fluid Ontology; Geological Entities; Crystal Structure Ontology.

35. COMPLETENESS CHECK
Required sections 01–35 present; root entity, types, relations, mathematics, validation, confidence, update model and AI consumption included.

END FLOW ALGEBRA — SEDIMENT ONTOLOGY