Pressure Transient Analysis

Buildup interpretation from raw gauge data — automatic QC and clock reconciliation, Bourdet derivative on superposition time, flow-regime identification, auto-window semilog, and matching against a 18-model analytical catalog ranked by AICc, through to deliverability and volumetrics. Gas & oil · 100% in your browser.
Results
Data & QC
Diagnostic
Semilog
Model matching
Deliverability

Gauge record & detected structure

QC never edits your data — spikes, frozen intervals and gaps are flagged and excluded from analysis, and the clock offset between gauge and reported schedule is estimated from the pressure breakpoints themselves.

Log-log diagnostic — Δp / Δm(p) and Bourdet derivative

Shaded bands are the detected flow regimes; dotted guide lines show the reference slopes (+1 storage, +½ linear, +¼ bilinear, 0 radial, −½ spherical) anchored on the identified segments, so the focus region of the analysis is visible at a glance.

Superposition semilog

Auto window maximises r² past the wellbore-storage guard (1.5 log cycles) — the objective criterion validated against published worked examples. Manual override: type a window and re-fit.

Candidate models

Ranking — statistical support, not truth

ΔAICc < 2 between models means this dataset cannot discriminate them — geology, seismic and offset wells must arbitrate. Parameter intervals are ±1σ (linearised); correlated parameters carry honestly wide bars.

Inflow (LIT) from PTA results

AOF is an extrapolation of the fitted inflow relation far beyond the tested rate window — quote it with the uncertainty of the match, never as a standalone certainty.
VLP curve CSV (optional) — q_mscfd, pwf_psia → operating point

Volumetrics

Any undetected boundary side must be entered as a RANGE (re-run with low/high), never a single number. p/Z EUR is volumetric depletion only — invalid under water drive.

Vertical lift performance

Two independent sources. Measured comes from the test itself — each stabilised step gives (q, pwh, pwf), so the tubing drop is observed, not modelled; it needs p_wh in the rate schedule. Correlation works at any THP but only as well as its assumptions. Match the correlation against the measured points before trusting it away from the tested rates.

Tubing & well

Fluid & correlation

IPR / VLP