JP Asia Pacific Updated 2026-08-20

Japan Geothermal Screening

Geothermal screening assessment identifies 44.8% prospective land reaching 185°C by 5.5 km depth in Japan.

Key Geothermal Metrics

Land Reaching 185°C by 5.5 km High Potential
44.8%

Primary baseline screening criterion

Shallowest Depth to 200°C Very Shallow
2.9 km

Minimum drill depth for high enthalpy

Peak Temperature at 5 km Depth Superhot
324.2 °C

Maximum modeled temperature

Typical Geothermal Gradient Volcanic / Rift
59.9 °C/km

Average to 5 km depth (15°C surface)

Grid Connectable Prospective Area Moderate Distance
70.6%

Hot territory within 50 km transmission

Stored Heat In-Place (3–7 km) 1 ZJ = 10²¹ Joules
243.6 ZJ

Thermal volume in place (>80°C baseline)

Depth vs. Temperature Matrix (% Land Area)

Proportion of national territory exceeding target isotherm at specified depth

0.1° Inversion Grid
Isotherm 3.0 km 4.0 km 5.0 km 6.0 km 7.0 km 8.0 km
150°C 21.8% 38.3% 65% 83.1% 99% 100%
175°C 18.8% 31.4% 50.9% 72.9% 94.4% 100%
200°C 17.1% 31.1% 43% 70.7% 83.8% 93.3%
225°C 13.3% 27% 42.3% 53.7% 75.7% 77.8%
250°C 11.4% 19.9% 35.7% 43.3% 59.4% 76.6%

4-Stage Geothermal Resource & Infrastructure Funnel

Progressive screening from gross national territory down to grid-connected & populated prospective zones

1 Whole country
377 975 km² 100%
2 Reaches 185°C by 5.5 km
169 333 km² 44.8%
3 ...and within 50 km transmission
119 549 km² 31.6%
4 ...and within 100 km town
111 899 km² 27.1%

Geological Setting & Subsurface Parameters

Lithology, basement thickness, stress and thermal boundary constraints

Median Depth to 200°C Isotherm 5.2 km
Best 10th Percentile Depth to 200°C 3.7 km
Median Temperature at 5 km Depth 210.9 °C
Best 10th Percentile Temp at 5 km 290.8 °C
Median Sediment Thickness 0.4 km
Sediment / Hard-Rock Well Share 36.8%
Territory Under 1 km Sediment Cover 94%
Lithostatic Pressure at 5 km Depth 138.5 MPa
Moho Crustal Discontinuity Depth 40.5 km
Thermal Lithosphere Thickness 104.9 km
Curie Temperature Isotherm Depth 16.9 km
Model Temperature Spread Uncertainty (200°C) ±1.1 km

Transmission Grid & Demand Colocation

Infrastructure interconnectivity and urban power demand proximity

High-Voltage Transmission Network Length 25 948 km
Land Area Within 25 km of Grid 57.9%
Land Area Within 50 km of Grid 70.6%
Land Area Within 100 km of Grid 75.9%
Average Proximity to Nearest Substation / Line 25.1 km
Urban Centers (>10,000 Population) 197
Total Urban Population 23.8 M
Prospective Resource Colocated Near Demand (>1M Pop) 64.7%

Target Sensitivity & Deep EGS Upside

Sensitivity of prospective resource area to adjusted depth and temperature thresholds

150°C Baseline at 5.5 km 71.7% of national territory reaches 150°C at 5.5 km depth
185°C Baseline at 7.5 km 80.6% of national territory reaches 185°C at 7.5 km depth

Global Peer Benchmarking (vs. 278 Assessed Jurisdictions)

Relative ranking distribution of Japan across 11 standardized geothermal indicators

Japan Rank Global Peer Spread
Shallowest 200°C depth
2.9 km Middle 50%
P0 (Lowest) P50 (Median) P100 (Highest) • 73th percentile
Peak temp at 5 km
324.2 °C Top 10%
P0 (Lowest) P50 (Median) P100 (Highest) • 90th percentile
Prospective land area (>185°C at 5.5 km)
44.8% Top 25%
P0 (Lowest) P50 (Median) P100 (Highest) • 75th percentile
Stored heat in-place (3-7 km)
243.6 ZJ Top 25%
P0 (Lowest) P50 (Median) P100 (Highest) • 75th percentile
Typical geothermal gradient
59.9 °C/km Top 25%
P0 (Lowest) P50 (Median) P100 (Highest) • 86th percentile
Grid proximity (<50 km)
70.6% Middle 50%
P0 (Lowest) P50 (Median) P100 (Highest) • 71th percentile
Thin sediment coverage (<1 km)
94% Top 10%
P0 (Lowest) P50 (Median) P100 (Highest) • 94th percentile
Curie isotherm depth
16.9 km Middle 50%
P0 (Lowest) P50 (Median) P100 (Highest) • 63th percentile
Moho crustal thickness
40.5 km Lower 50%
P0 (Lowest) P50 (Median) P100 (Highest) • 27th percentile
Model temperature uncertainty spread
±1.4 km Middle 50%
P0 (Lowest) P50 (Median) P100 (Highest) • 77th percentile
Urban demand colocation
37% Top 25%
P0 (Lowest) P50 (Median) P100 (Highest) • 67th percentile
Asset-Level 3D Simulation Available

Need Interactive 3D Spatial Inversion for Japan?

High-resolution 3D temperature cubes, localized Curie depth inversions, fault network stress tensors, and drilling capex curves for Japan are accessible through our Premium & Enterprise subscription tiers.

Direct Founder Contact: founders@geothermalradar.com

Analytical Geothermal Assessment & Discussion: Japan

Subsurface thermal interpretation, model uncertainty, infrastructure colocation, and resource quality analysis

Resource Overview

Geothermal assessment for Japan indicates volcanic_arc geological controls governing subsurface heat transport, yielding 44.8% of land area reaching the baseline target of 185°C at 5.5 km depth.

Uncertainty & Model Variance

Thermal inversion across Japan shows consistent model convergence with constrained standard deviations across deep crustal layers.

Grid & Infrastructure Colocation

National electrical transmission coverage positions approximately 70.6% of prospective geothermal ground within 50 km of existing high-voltage corridors.

Geological & Basement Setting

Subsurface lithology is characterized by volcanic arc dynamics with median sediment thickness of 0.4 km and crustal thickness of 40.5 km.

Stored Heat Volume

Accessible thermal energy in place between 3 km and 7 km depth above 80°C totals 243.6 Zettajoules (ZJ).

Peer Comparison

Benchmarked against 237 global assessment jurisdictions, Japan demonstrates competitive positioning across heat flow, infrastructure, and basement competence indicators.

Target Sensitivity Analysis

Screening at 150°C baseline at 5.5 km increases prospective territory, demonstrating substantial deep EGS resource headroom.

Screening Methodology, Parameters & Limitations

This screening assessment for Japan is generated from Geothermal Radar Data Pack 2026.1 utilizing global 0.1° hex-grid thermal inversion across 4 200 model cells (land area: 377 975 km²). Baseline prospective criterion is defined as reaching 185°C at or above 5.5 km depth with surface temperature normalized to 15°C.

  • Screening estimates represent regional-scale heat in place and do not replace localized 3D seismic or exploratory drilling.
  • Model uncertainties expand in regions with sparse deep boreholes and complex thrust fault kinematics.
  • Grid proximity indicators reflect line-of-sight distance to high-voltage transmission and do not account for local substation thermal capacity.
Need Detailed Asset-Level Due Diligence?

Access 3D temperature grids, drilling cost curves, and micro-siting GIS layers.

Request Full Technical Dossier