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| GEOLOGY OF GUJARAT |
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| Geo-logical Map of Gujarat |
Earthquake zone Map of Gujarat |
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| The state of gujarat comprises an area of approximately 1,96,000 sq.km and is enclosed within the North Latitude 20°10° to 24° 50° and East Longitude 68° 40° to 74° 40°. Geologically Gujarat provides a wide spectrum of rock types of different ages. Where as the Aravallies in the NE is as old as 2500 million years, the unconsolidated alluvium and beach material in its Central and Western parts, date back to a few thousand years only. All the important lithological types Ignious, Sedimentry and Metamorphic occur within the state. |
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Physiographycally the state of Gujarat comprises the following three distict zones.
1) Mainland Gujarat
2) Saurastra and
3) Kachchh |
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| The Gujarat state exposes rocks belonging to the Pre-cambrian, Mesozoic and Cenozoic era. The hard rocks cover about 49% of the total area of Gujarat,the rest being occupied by sediments of Quaternary period. The hard rock comprises Pre cambrian metamorphosed and associated intrusives, sedi- mantry rocks of Mesozoic and Cenozoic eras and the traps/flows constituting Deccan volcanic of Cretaceous Eocene age. The different geological formations occuring in various parts of Gujarat are shown in the "Geo- logical Map of Gujarat" (Plate-I). Genralised stratigraphy of Gujarat is given in Table. |
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| Stratigraphy of Gujarat |
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| Era |
Period |
Epoch |
Super group/ Formation |
Locality |
Age in Million Years |
| CENOZOIC |
QUTAERNARY |
HOLOCENE |
Undifferentiated sediments/Rann deposits |
Alluvial plains of Gujarat, Rann, Banni & Coastal deposits |
0.01 |
| PLEISTOCENE |
Chhaya formations/ Miliolite formation |
(1)Saurastra coast from Gopnath northwards extending beyond Porbandar |
1 |
| (2)Kachchh area |
| TERTIARY |
PLIOCENE |
Sandhan Formation |
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| MIO-PLIOCENE |
Dwarka Formation Jhagadia Formation |
Dwarka Okha Jhagadia |
12 |
| MIOCENE |
Gaj Formation Kand Formation Babaguru Formation |
Piram Island,Saurastra coast,Kachchh Jhagadia,Kand near Ankaleswar |
25 |
| OLIGOCENE |
Maniara Fort Formation |
Kachchh |
40 |
| OLIGOCENE-MIOCENE |
Kharinadi Formation |
Kachchh |
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| EOCENE-OLIGOCENE |
Tarkeswar Formation |
Tarkeswar (Surat dist.) |
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| EOCENE |
Fulra Formation Kakadinadi Formation Nummulitic Formation Vagadkhol Formation |
Kachchh |
60 |
| PALEOCENE-EOCENE |
Bhatia Formation Salod Formation |
Jamnagar Bharuch,Surat,Valsad, KhedaSabarkantha, Kachchh, Saurastra |
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| PALEOCENE |
Matanomadh Formation |
Kachchh |
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| MESOZOIC- CENOZOIC |
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CRETACEO-EOCENE |
Deccan Trap |
Parts of Sabarkantha, Panchmahals, Vadodara, Bharuch, Surat & Major parts of Valsad and Dangs, Major parts of Saurastra, Small parts of Kachchh |
110 |
| MESOZOIC |
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UPPER CRETACEOUS |
Lameta Formation Bagh Formation |
Kheda,Panchmahal,Narmada,Sabarkantha, Vadodara |
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| LOWER-MIDDLE CRETACEOUS |
Wadhavan Group |
Saurastra |
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| Bhuj Formation |
Kachchh |
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| Dhrangadhra Group |
Saurastra |
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| LOWER CRETACEOUS |
Himmatnagar Formation |
Sabarkantha |
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| JURASSIC CRETACEOUS |
Katrol (Jhuran) Formation |
Kachchh |
150 |
| UPPER JURASSIC |
Chari (Jumaran) Formation |
| MIDDLE JURASSIC |
Pachchham (Jhurio) Formation |
PROTERO-
ZOIC |
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NEOPROTEROZOIC |
Syn-to-Post Delhi intrusives |
Palnpur,Danta,Ider,Modasa, Taranga, Dharoi,Virpur, Wanakbori,Godhara |
| PALEO-MESO-PROTEROZOIC (Delhi Super group) |
Sirohi Group |
Banaskantha |
1500 |
| Kumbhalgarh Group |
Danta,Ambaji,Palanpur |
| Gogunda Group |
Khedbrahma,Shamalaji |
| PALAEO-PROTEROZOIC (Aravalli Super group) |
Champaner Group |
Chhotaudaipur,Shivrajpur, Jambughoda |
| Lunavada Group |
Modasa,Shamlaji,Lunavada, Baria |
| Jharol Group |
Modasa,Shamalaji |
| Udaipur Group |
Northen parts of Gujarat |
ARCHAEAN PROTERO-
ZOIC |
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Pre-Lunavada Gneissic Complex |
Kanjeta-Nadatod,Chhotaudaipur |
4000 |
| Pre-Champaner Gneissic Complex |
Jetpur,Sabarkantha,Panchm-ahal,Banaskantha,Vadodara |
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| Work done by Engineering Geological Division, Ahmedabad |
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| The jurisdiction of the Engineering Geological Division, Ahmedabad is the North & Central Gujarat Region i.e. Banaskantha, Sabarkantha, Mehsana, Patan, Gandhinagar, Ahmedabad, Kheda, Anand, Dahod and Panchmahals districts. The Division has carried out detailed geotechnical & geohydrological investigations and construction material quarry site exploration of various Major & Medium Irrigation scheme and Major Check dams of said district. The surface and sub-surface geotechnical and geohydrological investigation is carried out with the help of drilling, trenches, trial pits, collection of rock & soil samples for testing etc. To prepare geotechnical drawings and reports and submit the same to the C. D. O. & Project Authority. Also this Division has technical control of geotechnical investigation and finalisation of the geotechnical reports of different irrigation schemes of Kutch district. |
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| The three Engineering Geological Unit viz Ahmedabad, Godhra and Himatnagar are working under the Division and carried out the geohydrological and geotechnical investigation of different irrigation schemes of the said districts under guidelines and co-ordination. Also the drilling works, repairs & maintenance of machineries and vehicles are carried out by the Mechanical wing under the Division. |
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References
1) "Geology of Gujarat" by S.S.Merh published by Geological Society of India
2) "Geology of Gujarat" by V.N.Kulkarni (1985) published by Irrigation, R&B Deptt. Gujarat State in Journal "NAVNIRMAN" Vol. No.XXVII No.2
3) "Geology and Mineral Resources of Gujarat, Daman and Diu published by Geological Survey of India. Publication No.30 Part XIV-2001 |
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