important things to know

The Earth’s surface (the crust) is divided into seven major and several minor tectonic plates. The seven major tectonic plates are– North American Plate, South American Plate, Eurasian Plate, African Plate, Antarctic plate, Australian-Indian plate and Pacific plate. Minor plates also play an important role when it comes to the shaping the Earth. Some of […]

The lithosphere is broken up into many small sections/areas called crustal plates or tectonic plates. These tectonic plates fit into one another like jigsaw puzzle blocks. These plates are in constant motion but the movement is very slow that is about 3 cm per year. The motion of these tectonic plates is responsible for the

The Core: The core is the innermost, deepest, and the hottest layer of the Earth. It is believed that this part of the Earth is made up of two layers: an inner core (dark brown) and an outer core (yellow). The inner core is solid and the outer core is super-heated liquid molten lava. This

The crust is the outermost part of the Earth and is also called the lithosphere. The crust of the Earth is divided into two parts: continental crust and oceanic crust. The land part or continents are formed by the continental crust. The continental crust is made up of rocks that consist of primarily silica (Si)

When studied closely, we find that the Earth has a layered structure. It is made up of three main layers: the crust, the mantle and the core. The crust is the outermost part, the mantle is the middle layer and the core is the centremost layer. As we travel towards the core of the Earth,

The Earth is oblate spheroid (bulging at equators and flattening at poles) in shape. However, in the early days it was thought to be a flat piece of land. A major discovery with respect to the circumference and shape of the Earth was done in 25 BC. A Greek mathematician, named Eratosthenes, calculated the circumference

The Earth is a big ball-shaped moving body, mostly made up of rocks. It is the only planet in the solar system which has life. Life on the Earth became possible because of the availability of oxygen, the moderate temperature, the availability of water and the favourable atmosphere. It is the fifth largest planet of

Cenozoic era is the third major era after Precambrian period. The name Cenozoic was derived from the Greek word meaning ‘recent life’. This era is also called the ‘age of mammals’. Time Period: This era started around 70 million years ago, extending to the present time, in which we live. Features:♦ Flowering plants and insects

The Palaeozoic era was followed by the Mesozoic era. It was ‘the era of reptiles’, when dinosaurs ruled the world. It was the time of geologic and biological transition. It is divided into three major periods: Triassic, Jurassic and Cretaceous. Time Period: This era started 225 million years ago and lasted up to 70 million

The Precambrian time was followed by the Palaeozoic era. The first major period of this era was Cambrian Period (600 million to 500 million years). Major fossils show their earliest occurrence from this period. Time Period: It extends from around 600 million to 225 million years ago. Features:♦ The Palaeozoic is best known for explosion

Proterozoic eon is the third and last eon of the Precambrian time. Time Period: This eon extends from 2.5 billion to 600 million years ago. Features:♦ During this eon, the Earth started getting its present day shape and landforms arose. The Earth experienced global glaciation for the first time.♦ Life began to appear from simple

Archean eon or Archaeozoic is the second division of the Precambrian time. Time Period: It began around 4 billion years ago and extended till the beginning of Proterozoic eon 2.5 billion years ago. Features:♦ There were many volcanic gases in the atmosphere, but the dominating gas was carbon dioxide and the level of oxygen was

Hadean Eon is the first division of the Precambrian time. Time Period: The duration of this eon is between 4.5 billion (beginning of the Earth) to 4.0 billion years ago. Features:♦ This is the time when the solar system, including the Earth had just formed from the cloud of dust and gases. Those clouds and

Evolution of the Earth: Evolution of the Earth: Evolution is a process of gradual growth and development of life on the Earth from simple to complex form. Evolution of the Earth started around 4.5 billion years ago, when our solar system took shape due to the massive explosion of a small molecular ball called the