What Do You Need for the Geo-Scientist Exam?
Combined Geo-Scientist Exam 2027 at a Glance
UPSC’s exam for scientific posts in the Geological Survey of India (GSI) and the Central Ground Water Board (CGWB).
Application fee ₹200; women, SC, ST and PwBD candidates are exempt. Always confirm details on upsc.gov.in.
Posts and Vacancies (2027)
Tentative vacancies, as reported from the notification.
| Geological Survey of India | Group | Posts |
|---|---|---|
| Geologist | A | 29 |
| Chemist | A | 7 |
| Assistant Geologist | B | 34 |
| Assistant Geophysicist | B | 35 |
| Assistant Chemist | B | 6 |
| GSI total | 111 |
| Central Ground Water Board | Group | Posts |
|---|---|---|
| Scientist B (Hydrogeology) | A | 5 |
| Scientist B (Chemical) | A | 1 |
| Scientist B (Geophysics) | A | 1 |
| Assistant Hydrogeologist | B | 7 |
| Assistant Chemist | B | 1 |
| Assistant Geophysicist | B | 1 |
| CGWB total | 16 |
Total: 127 posts (111 in GSI, 16 in CGWB). Vacancies may change.
Who Is Eligible?
1. Age
At least 21 and under 32 on 1 January 2027 — born between 2 January 1995 and 1 January 2006.
2. Qualification
A master’s degree in the relevant subject — Geology, Applied Geology, Geophysics, Chemistry, Hydrogeology and others, as listed for each post.
3. Age relaxation
For SC/ST, OBC, PwBD, ex-servicemen and Central Government employees, as per rules.
4. One stream only
Choose a single stream even if you qualify for more than one.
Streams and Their Papers
Your stream decides your Prelims Paper II and all three Mains papers.
Geology
Geologist and Assistant Geologist (GSI).
Geophysics
Assistant Geophysicist (GSI, CGWB) and Scientist B Geophysics (CGWB).
Chemistry
Chemist and Assistant Chemist (GSI, CGWB) and Scientist B Chemical (CGWB).
Hydrogeology
Scientist B Hydrogeology and Assistant Hydrogeologist (CGWB).
Prelims Pattern Shortlisting
Two objective papers with negative marking. Prelims marks are used only to shortlist for mains.
| Paper | Marks | Time |
|---|---|---|
| I — General Studies (all streams) | 100 | 2 h |
| II — Stream paper (Geology / Geophysics / Chemistry / Hydrogeology) | 300 | 2 h |
| Total | 400 |
Mains and Personality Test
Three descriptive papers in your stream, then an interview. Final merit: mains + interview.
| Stage | Marks | Time |
|---|---|---|
| Mains — Paper I | 200 | 3 h |
| Mains — Paper II | 200 | 3 h |
| Mains — Paper III | 200 | 3 h |
| Personality test (interview) | 200 | — |
| Total | 800 |
Syllabus Overview
Postgraduate-level subject papers. Tap a subject to see its main areas.
General StudiesPrelims Paper I — all streams
- Current events of national and international importance
- History of India and the Indian National Movement
- Indian and world geography — physical, social, economic
- Indian polity and governance
- Economic and social development
- Environmental ecology, biodiversity and climate change
- General science
GeologyGeologist, Assistant Geologist
- Physical geology and geomorphology
- Structural geology and tectonics
- Mineralogy, petrology and geochemistry
- Stratigraphy and palaeontology
- Economic geology and mineral exploration
- Engineering geology and remote sensing
- Hydrogeology and environmental geology
GeophysicsGeophysicist, Assistant Geophysicist
- Solid earth geophysics and seismology
- Mathematical methods and signal processing
- Gravity, magnetic and electrical methods
- Seismic exploration methods
- Electromagnetic methods and well logging
- Physics topics — mechanics, electromagnetism, quantum and nuclear physics
ChemistryChemist, Assistant Chemist, Scientist B (Chemical)
- Inorganic chemistry — chemical bonding, coordination compounds
- Physical chemistry — thermodynamics, kinetics, electrochemistry
- Analytical chemistry — instrumental methods, spectroscopy
- Organic chemistry — reactions, mechanisms, spectroscopy
HydrogeologyScientist B and Assistant Hydrogeologist (CGWB)
- Origin, occurrence and movement of groundwater
- Aquifer properties and well hydraulics
- Groundwater exploration and quality
- Groundwater development, management and recharge
Free Geo-Scientist Study Material
Notes for General Studies and each stream.
These resources are being added subject by subject. Pages marked “Coming soon” are not published yet.
General Studies
Notes for Prelims Paper I.
Coming soon →Geology Notes
Topic-wise notes and diagrams.
Coming soon →Geophysics Notes
Methods, formulas and solved problems.
Coming soon →Chemistry Notes
Analytical, physical, inorganic and organic.
Coming soon →Hydrogeology Notes
Aquifers, well hydraulics and groundwater.
Coming soon →Mock Tests
Prelims papers in the real pattern and mains answer-writing practice.
Under development. The mock tests below are planned and will open here when ready.
Prelims Paper I
Prelims Paper II — Geology
Prelims Paper II — Chemistry
Mains Answer Writing
How to Prepare
About 11 weeks remain until prelims on 10 January 2027.
Focus on Paper II
The stream paper carries 300 of 400 prelims marks.
Don’t skip GS
Cover current events, polity, geography and environment for Paper I.
Solve past papers
UPSC repeats themes — practise previous Geo-Scientist papers.
Start mains early
Write long answers with neat diagrams, maps and equations.
Use standard texts
Rely on your master’s textbooks and revise key derivations and methods.
Prepare for the interview
Know GSI and CGWB’s work, recent missions and your own research.
CGSE 2027 Dates
Applications ran from 2 to 22 September 2026. Prelims: 10 January 2027. Mains: 19–20 June 2027, as reported. Always check the official website.
FAQs
What is the Combined Geo-Scientist Examination?
A UPSC exam to recruit geologists, geophysicists, chemists and hydrogeologists for the Geological Survey of India (Ministry of Mines) and the Central Ground Water Board (Ministry of Jal Shakti). Official information is on upsc.gov.in.
Who can apply?
Candidates aged 21 to under 32 on 1 January 2027 (born between 2 January 1995 and 1 January 2006) with a relevant postgraduate degree — Geology, Applied Geology, Geophysics, Chemistry and similar subjects as listed for each post.
Can I apply for more than one stream?
No. Even if you are eligible for more than one, you must choose a single stream when applying.
Is there negative marking?
Yes, in the objective prelims papers — one-third of the marks for a question are deducted for each wrong answer, as in other UPSC exams.
How is the final merit made?
Mains (600 marks) plus the personality test (200 marks). Prelims marks are used only for shortlisting.
Can final-year postgraduate students apply?
Check the notification — UPSC allows candidates appearing in the qualifying exam to apply in some cases, subject to submitting proof by the set date.