Why is the sea salty?

Answer 1

Sea water has been defined as a weak solution of almost everything. Ocean water is indeed a complex solution of mineral salts and of decayed biologic matter that results from the teeming life in the seas. Most of the ocean's salts are derived from gradual processes such the breaking up of the cooled igneous rocks of the Earth's crust by weathering and erosion, the wearing down of mountains, and the dissolving action of rains and streams which transported their mineral washings to the sea. Some of the ocean's salts have been dissolved from rocks and sediments below its floor. Other sources of salts include the solid and gaseous materials that escaped from the Earth's crust through volcanic vents or that originated in the atmosphere.

Past accumulations of dissolved and suspended solids in the sea do not explain completely why the ocean is salty. Salts become concentrated in the sea because the Sun's heat distills or vaporizes almost pure water from the surface of the sea and leaves the salts behind. This process is part of the continual exchange of water between the Earth and the atmosphere that is called the hydrologic cycle. Water vapor rises from the ocean surface and is carried landward by the winds. When the vapor collides with a colder mass of air, it condenses (changes from a gas to a liquid) and falls to Earth as rain. The rain runs off into streams which in turn transport water to the ocean. Evaporation from both the land and the ocean again causes water to return to the atmosphere as vapor and the cycle starts anew. The ocean, then, is not fresh like river water because of the huge accumulation of salts by evaporation and the contribution of raw salts from the land. In fact, since the first rainfall, the seas have become saltier.

The ocean is salty because of the gradual concentration of dissolved chemicals eroded from the Earth's crust and washed into the sea. Solid and gaseous ejections from volcanoes, suspended particles swept to the ocean from the land by onshore winds, and materials dissolved from sediments deposited on the ocean floor have also contributed. Salinity is increased by evaporation or by freezing of sea ice and it is decreased as a result of rainfall, runoff, or the melting of ice. The average salinity of sea water is 35 o/oo, but concentrations as high as 40 o/oo are observed in the Red Sea and the Persian Gulf. Salinities are much less than average in coastal waters, in the polar seas, and near the mouths of large rivers.

Source By Herbert Swenson
US Geological Survey Publication

Answer 2

Over millions of years the earth's surface is constantly uplifted and eroded. The detritus is both solid, and of varying size from boulders to silt, and dissolved ions. The sea is salty due to the vast amount of Na+, Cl- dissolved in it along with myriad other ions that contibute to the water's impurity. The sodium is dissolved out of sedimentary layers that will eventually form rock, and the chloride from volcanic activity and hydrothermal vents at mid ocean ridges where the plates are separating. There is roughly 35g of NaCl per litre of water in the ocean representing a salinity of approximately 3.5% although this varies depending on the local drainage, eg the Red Sea is evaporating more than it is refreshed and is more saline while deltas etc which have fresh water run off are less saline than the ocean as a whole.
hope this helps answer ure question.

Answer 3

There are two universal truths that could explain this.

First is that most of earth is covered by water. So water is far more widespread than land.
Second is that water dissolves salts.

Now based on these two statements.... Water is more widespread and it easily dissolves all the salt present in those areas(ocean beds, rocks, minerals, etc.). Apart from these seabeds are actually low lying areas and all particulates from the land above are swept into them by rivers/ waterways/ rains etc. now u could ask me in that case y dont these taste salty too,... the reason is that they carry salts for small time intervals(like one rain sweeps out one batch of salt n the next one takes the next batch and so on..) whereas oceans remain for ages. n hey where can these dissolved salts go anyway??? So they just continue to stay in the ocean n hence the ocean is salty...

Answer 4

When the earth was in its beginings and the seas were bieng formed through rain and percipitation the water sitting the earth's crust dissolved the minerals in the rock over time (millions of years) causing the sea to be "salty".

Answer 5

Because salt and other minerals were carried into the sea by rivers, having been leached out of the ground by rainfall runoff.

Upon reaching the ocean, these salts would be retained and concentrated as the process of evaporation removed the water.

Answer 6

The sea contains both alkali and alkine earth metals that when reacted with a halogen, form a salt (eg, CaCL, NaCL, KCL etc)
These deposits of minerals make up the sea bottoms and react readily to form salts

Answer 7

The average blue whale produces over 400 gallons of sperm when it ejaculates, but only 10% of that actually makes it into his mate. So 360 gallons are spilled into the ocean every time one unloads, and you wonder why the ocean is so salty...

Kidding, what the others said, but wouldn't it be funny (and/or gross) if this was true?

Answer 8

When planetary ocean formatting, many-many years ago, the H2O (water) combined with salt deposits beneath the earth. And no, water cycle in nature have no role in this, if it had, the lakes, rivers was salty too.

Answer 9

The salt came from eroded salts from the land masses and the ocean floor.

Answer 10

Because it is fed by rivers and streams that over millennia have dissolved rocks and then poured into the seas.