THRESHOLD COMPLEX EXPLORATION LOG
Designation / Log ID: 23-T20
Apparent Date/Time: 26 August 2026 / 09:04 (local) — secondary stamp reads 03:41 22 March 1983
Entry Method: Single steel fire door marked “E-14 ESCALATOR WELL”. Door opens inward. Panic bar on interior side. Exterior handle absent.
Environmental Baseline
Lighting: continuous fluorescent tubes, color temperature measured at 4100 K. Intensity constant at 185 lux.
Ambient temperature: 19.4 °C. Humidity: 58 %.
Background sound: low-frequency hum at 48 Hz. Amplitude 22 dB.
Air movement: downward draft of 0.4 m/s along the well. Barometric pressure 1012.1 hPa on entry; 1015.6 hPa after 6 m of descent.
Spatial Observations
Well estimated 18 m deep by 4.2 m wide. Laser measurement returns 11 m deep by 6.8 m wide.
Floor of entry landing: ribbed rubber matting. Surface temperature 3.2 °C below ambient.
Walls: painted concrete. Original color visible in patches. Wall temperature matches ambient.
Ceiling of entry landing: 2.7 m. Escalator steps visible descending. Step count remains fixed at 42 after repeated inventory.
Repeating motif: every 1.8 m a side-mounted light fixture is present. Fixtures measure 0.4 m by 0.15 m by 0.1 m. Diffusers display identical scratch patterns.
Anomalies
Visual count of escalator steps returns 42. Physical inventory returns 42. Step width measures 1.1 m while total well width measures 6.8 m.
Landing remains level under spirit level. Measured slope along the direction of travel is 3.4° toward the lower level. Slope reverses after 4 minutes of continuous observation without change in physical orientation.
Handrail speed measured at 0.6 m/s while step progression measures 0.0 m/s. Handrail temperature measures 27.1 °C regardless of ambient.
Sound of step engagement arrives 2.1 seconds after corresponding motion is detected. Delay increases by 0.4 s for every additional 3 m of descent from entry point.
Humidity at mid-well remains 58 % while condensation forms on the handrail after 5 minutes of contact. Condensation evaporates without measurable change in local humidity.
Entity Notes
None observed.
At the 9 m mark a localized pressure spike of 4.2 hPa occurs across a 2.1 m radius. Spike persists for 6 seconds then collapses. No visible source or airflow change accompanies the event.
Exit / Continuity Status
Exit achieved by retracing path to the steel fire door. Panic bar released with moderate resistance.
Exterior time on exit: 09:41 local. Elapsed interior time: 37 minutes. Wristwatch confirms same interval.
Residual effects: residual low-frequency hum audible for 14 minutes after exit. Temporary inability to resolve step edges beyond 2 m lasting 8 minutes. No other reported sequelae.