Oku no Yu Gensen
Analysis VerifiedOku-no-yu source stands as one of Noboribetsu's signature thermal springs, naturally gushing from the lake bed of a crater formed by Hiyoriyama's ancient explosion—a basin roughly 200 meters in diameter. Adjoining the Oyunuma, this source dramatically erupts from cone-shaped "fuki" vents, expelling vigorously churning sulfurous waters tinged gray-black and white. The billowing steam clouds and violently bubbling hot-spring cauldrons evoke the very image of earth's violent depths. These waters flow to neighboring inns throughout Noboribetsu, cherished as one of the region's most celebrated thermal treasures.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
Undissociated boric acid with antibacterial action that keeps the skin surface clean.
The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.
Scores are calculated from mineral analysis data based on the Mineral Spring Analysis Guidelines (Ministry of Environment, Japan). They are unrelated to facility atmosphere or service quality.
The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.
Because the source temperature is extremely high, the water is naturally cooled to comfortable bathing temperature as it travels through facility pipes. The weakly acidic sulfur-rich waters may irritate sensitive skin; after bathing, we recommend rinsing gently with cool shower water to minimize irritation and preserve the thermal experience.
At pH 3.8 with 709.4 mg/kg dissolved chloride ions, these weakly acidic waters purify the skin while the salt content forms an invisible thermal barrier against heat loss. Ideal for those suffering from peripheral circulation disorders or chronic cold sensitivity, this mineral composition warms the body's core, dissolving daily fatigue and tension with remarkable efficacy.
Those with sensitive skin or mucous membranes, and elderly visitors with dry skin conditions, should exercise caution before bathing. This source water is not suitable for drinking.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- 奥の湯
- Spring type
- 含硫黄－ナトリウム・カルシウム－塩化物温泉 (硫化水素型)
- Old spring type name
- 含塩化土類－食塩硫化水素泉
- Source temperature
- 64.2℃
- pH
- 3.8
- Flow rate
- 75 L/min
- Flow type
- 自然湧出
- Osmotic pressure
- 低張性
Analysis Document
- Analysis date
- 2018-06-29
- Analyst organization
- 北海道立衛生研究所
- Registration No.
- 北海道第1号
Cations
- Hydrogen ion H⁺
- 0.20 mg/kg
- Sodium ion Na⁺
- 267 mg/kg
- Potassium ion K⁺
- 79.9 mg/kg
- Ammonium ion NH₄⁺
- 0.10 mg/kg
- Magnesium ion Mg²⁺
- 4.9 mg/kg
- Calcium ion Ca²⁺
- 124 mg/kg
- Aluminum ion Al³⁺
- 1.0 mg/kg
- Manganese ion Mn²⁺
- 1.8 mg/kg
- Iron(II) ion Fe²⁺
- 2.2 mg/kg
- Iron(III) ion Fe³⁺
- 0.00 mg/kg
- Lead ion Pb²⁺
- 0.00 mg/kg
- Total cations
- 0.48 mg/kg
Anions
- Fluoride ion F⁻
- 0.20 mg/kg
- Chloride ion Cl⁻
- 709 mg/kg
- Hydrogen sulfide ion HS⁻
- 0.00 mg/kg
- Thiosulfate ion S₂O₃²⁻
- 11.4 mg/kg
- Sulfate ion SO₄²⁻
- 46.6 mg/kg
- Bicarbonate ion HCO₃⁻
- 0.00 mg/kg
- Carbonate ion CO₃²⁻
- 0.00 mg/kg
- Bromide ion Br⁻
- 5.8 mg/kg
- Iodide ion I⁻
- 1.3 mg/kg
- Hydrogen sulfate HSO₄⁻
- 0.20 mg/kg
- Total anions
- 0.77 mg/kg
Undissociated Components
- Arsenious acid HAsO₂
- 0.50 mg/kg
- Metasilicic acid H₂SiO₃
- 93.9 mg/kg
- Metaboric acid HBO₂
- 51.7 mg/kg
- Total undissociated
- 0.15 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 141 mg/kg
- Free hydrogen sulfide H₂S
- 9.6 mg/kg
- Total dissolved gas
- 0.15 mg/kg
Totals
- Total dissolved substances
- 1.4 mg/kg
- Component total
- 1.6 mg/kg
- Evaporation residue
- 1.7 mg/kg
Usage
- Heating
- No
- Dilution
- Yes
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- No
Indications & Contraindications
- Bathing indications
- Chronic pain or stiffness in muscles and joints (Rheumatoid arthritis, Osteoarthritis, Lumbago, Neuralgia, Frozen shoulder, Bruises, Sprains in chronic phase), Muscle stiffness due to motor paralysis, Gastrointestinal dysfunction, High blood pressure (mild), Impaired glucose tolerance (diabetes), Mild dyslipidemia, Mild asthma or emphysema, Hemorrhoid pain, Autonomic instability, Stress-related symptoms (Sleep disorders, Depression), Recovery from fatigue, Health promotion, Atopic dermatitis, Psoriasis vulgaris, Chronic eczema, Epidermal purulent disease, Peripheral circulatory failure, Cuts and grazes, Poor circulation, Depression, Xeroderma
- General indications
- Chronic pain or stiffness in muscles and joints (Rheumatoid arthritis, Osteoarthritis, Lumbago, Neuralgia, Frozen shoulder, Bruises, Sprains in chronic phase), Muscle stiffness due to motor paralysis, Gastrointestinal dysfunction, High blood pressure (mild), Impaired glucose tolerance (diabetes), Mild dyslipidemia, Mild asthma or emphysema, Hemorrhoid pain, Autonomic instability, Stress-related symptoms (Sleep disorders, Depression), Recovery from fatigue, Health promotion
- Contraindications
- Active stages of disease (especially with fever), active tuberculosis, advanced malignant tumors or severe anemia resulting in significant physical debilitation, severe heart or lung diseases causing shortness of breath with slight exertion, severe kidney diseases with edema, gastrointestinal bleeding, visible bleeding, acute exacerbations of chronic diseases, hypersensitive skin or mucous membranes, xeroderma in the elderly
Drinking
- Drinkability
- Not drinkable
- Drinking notes
- This hot spring is not used for drinking.
