Early Pre-Historic

• Oldest known rocks

• First cellular life (microbes)

• Likely hydrothermal or shallow-water environments

• Expanding microbial life

• Stromatolites formations appear due to microbial mats

• Early continental crust

Indian Craton (Singhbhum nucleus):

• Singhbhum craton: ~3.5–3.3 BYA → 

  • Some of the oldest rocks in India. Formed during early Archean continental crust formation. 

  • Represents one of Earth’s oldest crustal fragments, existing as a small, isolated proto-continental block.

• Widespread stromatolites

• Early photosynthesis

• Growing continents

• Oxygenic photosynthesis increases

• Banded iron formation

• Transition toward oxygenated atmosphere

Indian Craton:

• Almost stabilized: ~2.5 BYA → stable continental block.

• Dharwar craton: growth and stabilization.

• Widespread cyanobacteria

• Great Oxidation Event

Indian Craton:

• Final stabilization of most Indian cratons: ~2.5 BYA (general timeline, not absolute).

• Assembly of larger Indian shield via mobile belts (e.g., Central Indian Tectonic Zone).

• No longer juvenile crust.

• Low but stable oxygen levels

• Cyanobacteria persist, but decline in relative dominance

• Diversification of eukaryotes—

  • Organisms with cells containing a nucleus and complex internal structures. 

  • This includes: animals, plants, fungi, protists (mostly unicellular eukaryotes, including algae)

• Multicellular eukaryotes: ~800 MYA

• Ediacaran or Vendian Period: ~635 to 542 MYA → First animals; Soft-bodied organisms.

• Transition to Cambrian ecosystems;

• Gondwana assembly begins and progresses.

• Gondwana present; other major continental blocks

• Cambrian Explosion of life

• Most major animal phyla appear

Indian Craton:

• Had been tectonically stable for over 2 billion years.

• East Gondwana: ~541 MYA → 

  • Part of Neo-proterozoic Gondwana assembly; 

  • In the Southern Hemisphere; firmly attached to Antarctica, Australia, and Madagascar.

• First simple land plants

• First major mass extinction

• Glaciation of southern Gondwana

• Seafloor sediments of Tethys Ocean formed (due to later uplift, ancient Ordovician ocean rocks now sit at Mt. Everest).

Indian Craton:

• East Gondwana: Positioned at the high southern latitudes. 

• Likely affected by the Gondwana glaciation, while remaining tectonically stable.

• Ice age ends

• Fish diversify and spread

• Early vascular plants expand on land 

• Age of Fishes

• Ammonites diversify (coiled shelled marine organisms)

• Forests emerge and spread

• Landmasses: 

  • Gondwana remained a large southern supercontinent. 

  • In the Northern Hemisphere, Laurussia (Euramerica) was formed from earlier continental collisions. 

  • Siberia and the China blocks remained separate.

• Laurussia and Gondwana collide; initiating the Pangea

• China and Siberia remained separate landmasses.

• Major mountain formations due to continental collision

Indian Craton:

• Not a primary (orogenic) zone of collision, but involved in Pangea assembly.

• Pangea → all continents and landmasses fused

• Panthalassa → one ocean surrounds Pangea

• Seeding plants, insects & reptiles diversify

• Largest Mass Extinction: Largest biological crisis in Earth’s history (~90% species lost)

Indian Craton:

• Part of southern Pangea, located south of the equator.

• Tectonically stable, but part of the global biological crisis.

• First dinosaurs

• First Mammals: Small, fur-bearing, reptile-like

• Mini-Mass Extinction

• Pangea begins to split; Atlantic Ocean opens

• Dinosaurs and flying pterosaurs thrive

• First birds; early mammals (in small numbers)

Indian Craton:

• During Pangea split: Attached to the southern remnants of Pangea (Gondwana). 

• Dinosaurs: Presence inferred; Indian craton was physically connected to other Gondwanan landmasses—Africa, Antarctica, South America—well known to have dinosaurs.

• High sea levels

• Continued continental breakup

• Mass Extinction: End of period; Non-avian dinosaurs and large reptiles disappear.

Indian Plate (not craton anymore):

• Separated: ~130–120 MYA → Indian plate detached from Antarctica–Australia (Africa already separated earlier).

• Independent: ~120–100 MYA → Rapidly moving Indian plate, fully detached from Gondwana.

• Drifted: ~100–70 MYA → Indian plate drifted northward very rapidly across the Tethys Ocean (toward Eurasia), moving from Southern Hemisphere toward equator and then crossing it later.

• Dinosaurs: Cretaceous dinosaur fossils found—Jabalpur, Kutch Basin, and Narmada Valley (in Madhya Pradesh and Gujarat); Lameta Formation (in central and western India); Pranhita–Godavari Basin (in Telangana–Andhra)

• Indian dinosaurs: Rajasaurus–large theropod carnivore; Isisaurus–sauropod herbivore

• Mammals diversify after dinosaur extinction

• Continents move toward modern configurations

Indian Plate:

• Crossed Equator: ~70–55 MYA → 

  • Continued moving north at unusually high speeds (~15–20 cm/year). 

  • Tethys Ocean lay between the Indian and Eurasian plates.

• Warm global climate

• Major mammal diversification

• Early Primitive Primates: rodents, herbivores, eohippus (horse ancestor), elephant ancestors, whales, bats, etc.

Indian Plate:

• Part of Eurasia: ~55–50 MYA → Indian plate moves exceptionally fast; collides with Eurasian plate.

• Himalayan range: ~55–50 MYA → 

  • Seafloor of Tethys Ocean subducted. 

  • Crust thickened and Himalayan range uplift begins (which continues even today).

• Elephant ancestors (stem proboscideans): ~54–50 MYA → Primitive elephant relatives (anthracobunids)—small, hoofed animals; fossils at Cambay Shale, Western India.

• Cambaytherium: ~55–54 MYA → a distant cousin of Eohippus (horse ancestor); an early perissodactyl side branch that didn’t give rise to later lineages; might’ve gone extinct.

• Further mammal evolution (first elephants, early horses)

• Grasses present; many types of grasslands expand

• Global cooling and drying trend.

Indian Plate (sutured to Eurasian Plate after this):

• Elephant-lineage animals (proboscideans): ~40–25 MYA → 

  • Dispersed into South Asia after India’s collision with Eurasia. 

  • Larger-bodied, more elephant-like forms appear.