Wellbore Genius
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Live physics tuning

Drag a constant and every published reference stage re-solves through the same whole-pad kernel /pad-parallel uses. Half-length and height are shown against the measured field value, with the shift from the fitted constants in the last column of each pair.

Kernel constants
Fitted
Saved to this browser and used by every pad-scale run in the app.

Off runs the legacy zero-leak-off closed form.

ft/√min

Higher leak-off means shorter, fatter fractures. Fitted to MSEEL fibre half-lengths.

ft

Instantaneous fluid loss at first exposure of new fracture face.

-

Exposure-time shape factor. 1.47 is the standard PKN value.

psi

Net pressure must exceed this before height grows out of pay. Raise it for bounded stacks.

psi/ft

How fast confinement builds once height grows past the barrier.

ft

Hard ceiling on total fracture height, e.g. a regional frac barrier.

psi/ft

How fast closure stress varies inside the pay. Higher means the fracture opens less of the pay interval; 0 pins height to full pay thickness. 1.1 is the HFTS-1 core fit.

Share of the pumped proppant that forms the pack in the main fracture; the rest goes to secondary strands, near-well banking and flow-back. 0.54 is the HFTS-1 core fit.

Porosity of the settled pack. Higher porosity means the same mass fills more fracture, so the propped extent is longer.

in

Grain d50. 0.0118 in is 40/70 sand, 0.0197 in is 30/50. Only bites when the fracture narrows to the bridging width.

Proppant cannot pass a fracture narrower than this many grain diameters, which caps how far the pack can travel.

How fast the propped tip advances with pumped proppant. 0.8 is the pure width taper; lower values mean the bank stacks thicker near the wellbore, so the propped tip advances more slowly. Fitted to the five HFTS-1 through-fracture cores.

ft

Height of the settled proppant bank that carries the pack. Only this band of the fracture takes proppant, so propped extent tracks pumped mass instead of total fracture height — which is what the HFTS-1 cores show. Raise it to let tall fractures prop over their full height.

Floor on the fraction of pay the fracture always opens across the perforated interval.

psi

Width of the transition at the barrier. 0 is a hard threshold, so height stops responding to barrier contrast whenever net pressure is below it. 40 psi is the HFTS-1 core fit.

Share of each side's barrier contrast that also holds the outermost pay shut, solved separately above and below the perfs. This is what makes stage-to-stage barrier differences move fracture height. 0.4 is the HFTS-1 core fit.

Like-for-like accuracy
Across 16 comparable checks on 2 published pads.

Mean |Δ|

4.98%

Worst |Δ|

16.5%

Path

Calibrated

HFTS-1 Midland Basin Wolfcamp core-through-frac
mean |Δ| 2.60%
worst 9.7%
Ciezobka, J. et al. (2018). Overview of Hydraulic Fracturing Test Site (HFTS-1) in the Permian Basin. URTeC-2937168. · Gale, J. F. W. et al. (2018). Natural fractures in the Wolfcamp Formation and their effect on hydraulic fracture propagation. URTeC-2902624. · Raterman, K. T. et al. (2019). Analysis of a drained rock volume: an eagle ford example. URTeC-2019-263-EG (methodology reference).
Stage½-length modelmeasuredΔvs fittedHeight modelmeasuredΔvs fittedpnet
stage-a
PKN
245240+2.0%170170+0.1%125
stage-b
PKN
271265+2.2%188187+0.4%86
stage-c
PKN
230210+9.7%145145+0.2%134
stage-d
PKN
262285-8.1%208208-0.1%83
stage-e
PKN
258250+3.2%178178+0.0%89

All lengths in ft, net pressure in psi. “n/c” marks a pair that is not the same physical quantity (hydraulic extent against core propped extent, fracture height against a DAS cloud) — read those as ratio sanity checks, never as accuracy.

MSEEL MIP-3H Marcellus completion + DAS/MS
mean |Δ| 8.95%
worst 16.5%
Carr, T. R. et al. (2017). Marcellus Shale Energy and Environment Laboratory (MSEEL). URTeC-2670867. · Wilson, K. et al. (2018). Fiber-optic monitoring of hydraulic stimulation at MSEEL. SPE-189889-MS.
Stage½-length modelmeasuredΔvs fittedHeight modelmeasuredΔvs fittedpnet
stage-04
PKN
795720+10.4%169260n/c87
stage-08
PKN
791780+1.4%170285n/c84
stage-12
PKN
741690+7.5%165245n/c87
stage-16
PKN
685820-16.5%169300n/c76
stage-20
PKN
760740+2.8%169270n/c85
stage-24
PKN
678800-15.2%166290n/c77

All lengths in ft, net pressure in psi. “n/c” marks a pair that is not the same physical quantity (hydraulic extent against core propped extent, fracture height against a DAS cloud) — read those as ratio sanity checks, never as accuracy.