The Caspian Sea probably formed this way. It should be noted that seas do not have to be formed over continental crust and can form anywhere that a body of water is partially enclosed by land. Seas, particularly epicontinental seas, can contain abundant deposits of sand, silt, and mud derived from rivers which empty into the sea through deltas.
Sediments from rivers on Earth are predominantly siliciclastic, meaning that they are predominantly made of silicate minerals such as quartz, feldspar, and mica. They become lithified into rocks such as sandstone and mudstone. Seas with minimal sediment influx from deltas, however, will contain sediment with more carbonate minerals such as calcite.
These sediments can be lithified into limestone. When a sea is warm and there is minimal input of siliciclastic sediment from rivers, carbonate mineral-bearing grains will make up most of the sediment on the seafloor. Carbonate grains are often microfossils composed of the preserved carbonate shells of organisms which once lived in the surface water and descended to the seafloor when they died to became future grains in a limestone. These grains can also be made of directly precipitated carbonate minerals in the case of ooids, pisoids, and micrite carbonate mud.
When carbonate grains lithify, they can become Limestone. Limestone and sandstone deposits which formed in ancient epicontinental seas make up the primary bedrock of much of the land surrounding the modern Mediterranean Sea.
Because seas form when water is partially surrounded by land, and the position between the land and the adjacent body of water can change regularly due to plate tectonics and physical erosion, the position of the shoreline constantly shifts as the continents move and the sea level changes. The geologic record left behind in the process is called a transgressive sequence.
In a transgressive sequence, the grains making up the rock layers become finer or smaller from deeper layers to shallower layers. This is referred to as a fining upward sequence. In a regressive sequence, the reverse occurs, and it is called a coarsening upward sequence. The sequence coarsens upward in a regressive sequence because, as the sea level retreats, beach sand is deposited on top of the mud deposits associated with offshore marine environments. The transgressive sequence is the reverse because the grains get finer as old beach deposits become buried and overlain by marine mud and silt as the sea level rises.
Both sequences are common along the margins of seas and can indicate the presence of ancient seas as well as lakes. Sometimes, when sea level drops, irregularities in topography can create landlocked remnant seas, essentially giant lakes. That is where there is a difference between oceans, seas, gulfs, and more are present. The difference between an Ocean and Gulf is that an Ocean refers to a large water body that consists of saltwater.
These regions are far from the mainland. On the other hand, a gulf consists of a smaller water body present close to the land. An Ocean consists of a large expanse of water. They are known to be the main source of distribution of water to other water bodies.
This is because an ocean divides into seas. One considers a sea to a gulf in certain circumstances. An ocean can also become a bay upon dividing further. An ocean consists of saltwater. The salt concentration is barely two percent of the total water concentration. Marine fish thrive in this water. Other organisms like invertebrates are also present.
The Pacific Ocean is the largest. The Mariana Trench is home to a number of deep-sea creatures. It is around 36, feet or 11 kilometers in depth. Therefore, the two waterbodies significantly differ in their indentation and enclosure. It is much smaller than Bay of Bengal.
It is clearer now why it is not called the Gulf of Bengal. The definition gives the answer. Nice to know. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment.
Key Differences Between Bay and Gulf The difference between gulf and bay can be drawn clearly on the following grounds: Bay is described as a large waterbody, which forms an indentation of the shoreline, such that the sea is covered by the coast from maximum sides. On the contrary, the gulf is defined as the large body of the ocean which is almost covered by land, except a narrow opening from one side.
River management has redirected the flow of the Mississippi River. Canal s, dam s, and drainage system s for agriculture and industry have provided power and irrigate d land.
They have also reduce d the wetland s at the rivers mouth and delta. The Gulfs wetlands slow storms as they move toward land. The loss of these wetlands may have contributed to the destruction brought by Hurricane Katrina to the Gulf Coast between central Florida and Texas in Because both the sea and the gulf are shallow, the exchange of water between the two is reduced.
Sediment collects at the mouth of the gulf, forming underwater barriers. The low shore is bordered in some areas by wetlands and swamp s. This shallow gulf with a wide mouth creates the conditions for a yearly spectacle called the Morning Glory Cloud.
In September and October, sea breeze s from the Gulf of Carpentaria and the Arafura Sea meet and create an enormous , fast-moving cloud over the gulf. The Morning Glory Cloud can be 1, kilometers miles long and move at a rate of 60 kilometers per hour 37 miles per hour. Vast deposits of petroleum in this region make the Persian Gulf strategic ally important.
Middle East ern countries depend on the gulf for trade and for access to the Indian Ocean. All countries that consume oil from the region, including the U. Bridging the Gulf The Middle Eastern countries of Bahrain and Qatar have reached an agreement to build the world's longest oversea bridge, which will span 40 kilometers 25 miles over the Persian Gulf. The bridge, which is expected to be completed by , will cut the travel time between the two countries from five hours to 30 minutes!
Hurricanes are the same thing as typhoons, but usually located in the Atlantic Ocean region. Usually rivers enter another body of water at their mouths. Regions are the basic units of geography. Also called lithospheric plate. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Caryl-Sue, National Geographic Society.
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