Zusammenfassung der Ressource
Flussdiagrammknoten
- Cleanse data and apply corrections (baro, temp)
- Graph: elapsed time, displacement, flow rate, activity
- Plot hydrograph and annotate
- Establish likely conceptual flow model
- Download and view logger data
- Obtain all required bore and aquifer input data
- Check units and conversions
- Set up file for analytic model
- Use software wizard and review tutorials
- Plot data and perform Diagnotics
- Check derivative curve catalog
- Review log-log and semi-log
- Flat derivative indicates IARF and validity of C-J straight line
- Does flow model fit with geology?
- Choose appropriate solution
- Compare with other solutions and expected values
- Perform sensitivity analysis on T & S, Kv/Kh
- Are analysis assumptions valid?
- Use C-J semi-log straight line on late-time data when IARF
- Check Aqtesolve course notes
- Check for d-d curve inflections
- Residual d-d late time is near graph origin (reverse plot)
- Logan (confined) T=1.22.Qmax/smax
- Logan (unconfined) T=2.43.Qmax.bsat/(smax.(2b-s))
- Unconfined aquifer S=Sy (0.1-0.3)
- Specific Capacity=Q/s (m3/d/m)
- Skin Factor Sw= Aquifer Loss: BQ Well Loss: CQ
- Batu-Driscoll (unconfined) T=1.042(Qmax/smax)
- Batu-Driscoll (confined) T=1.385(Qmax/smax)
- Screen over water table: Semilog plot inflection. Fit later data
- Early straight line unit slope of both plots on log/log = well bore storage dominant
- If derivative does not plateau then don't use straight-line analysis
- Early Data: bore storage
Mid Data: flow model ID
Late Data: boundaries
- Model-building procedure:
1.data mgt
2.diagnostics
3.model selection
4.curve matching
5.statistical analysis
- Deviation from unit slope as more water comes from aquifer
- log-log derivative drops to zero if leaky aquifer or constant head boundary
- The tail of derivative curve can be unreliable
- C-J gives best results for single well tests as removes skin effect
- Single well S biased by skin. Very low S = redevelop bore!
- Partial penetration gives similar curve to skin
- Theis recovery residual d-d method: t/t' intercept close to 1 = infinite aquifer. <1=no flow boundary. >1=recharge boundary
- Recovery methods:
Argawal time Theis curve match
Argawal C-J plateau late time match
Pap-Coop match d-d & recovery data
Residual d-d Theis late time thru origin
- Perform approximation calculations
- Compare multiple values of T&S