The first hypothesized period of planetary-scale chilling or glaciation does not occur until about half-way through Earth’s history at 2.2 billion years ago during the Proterozoic era. Less than a billion years ago, Earth is believed to have experienced a severe freezing episode resulting in what has been called ‘Snowball Earth’. 1st Snow Ball Earth […]
An unusual warming event known as Sudden Stratospheric Warming (SSW) has been observed over Antarctica and Arctic which is also found to be linked with an ozone hole shrinking over the pole. SSW refers to this warming in the stratosphere, a rapid warming (up to about 50-°C in just a couple of days), between 10
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Sediment can be consist of either mineral or fossil particles, and both types can be found in many places on the bottom of the sea. Classification of marine sedimentation :- The sedimentation can be subdivided on the basis of the size of the particles or on the basis of their mode of formation. Factors that
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The oceanic mixed layer (OML) is the ocean region adjacent to the air-sea interface and is typically tens of meter deep and due to the fact that it is well mixed, the temperature and salinity are fairly uniform. The rapidly changing below these uniform regions of temperature , salinity and density are called thermocline, halocline
A dynamic topography map provides the information about horizontal circulation of the waters and magnitude of the flow at different depths. Ocean currents are mapped by studying the hills and valleys in maps of the sea surface height relative to the geoid, known as ‘Dynamic ocean topography’. Currents move around ocean dynamic topography hills &
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Separation of a liquid from the partially melted solid residue is a form of diversification because it involves partitioning and separation of chemical constituents, and it can produce a variety of melt compositions from a single source. When the interfacial energy (surface tension) of the melt is similar to that of the minerals, the dihedral
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Ophiolites are considered to be masses of oceanic crust and upper mantle thrust onto the edge of a continental or incorporated in mountain belts, where they are tectonically disrupted and now exposed by erosion. A typical Ophiolite, in this case based primarily on the Semail Ophiolite in Oman on the Arabian peninsula, a particularly well
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The rise of Himalaya has been related with the northward drift of the Indian Plate and it’s consequent collision with the Eurasian Plate. Paleomagnetic data from the floor of the India ocean suggests that the northward drift of the India Plate was most rapid during the Paleocene Epoch. This was also the time of the
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In paleontology fossils can be of many types as explained below – Body fossils :- These are well preserved entire organism, unaltered and altered hard parts and naturally formed moulds and casts (+ vs and -ve impression) are called as body fossils. Chemical fossils :- These are well preserved paleo-proteins and amino acids (paleo-biochemistry) and
Petroleum is hydrocarbon, with minor amount of Nitrogen, Oxygen and Sulfur as impurities along with heavy metal. Source of petroleum is organic. It contains CH4 chains that are linked together to form long chains of more complex molecules. Petroleum occurs in the earth in combination of any of the many states like gas, liquid (crude
