Sedimentary rocks are formed through the accumulation and lithification of sediment (particles of minerals, organic materials, or other rocks) that are deposited on the Earth's surface. Over time, these sediments are compacted and cemented together by minerals precipitating from groundwater, creating layers known as strata. Examples include sandstone, shale, and limestone. They often preserve fossils and provide clues about Earth's history and past environments.
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00:00Sedimentary rocks are the rocks that are formed by depositing sediment in a place and solidifying it.
00:13There is a process in this.
00:15In this, I will discuss the weathering agent and the original agent.
00:20When you have forces on the mountainous area that are trying to balance the earth,
00:26you can also say that there are disintegration forces that are trying to balance the earth.
00:31Among them, there is water, obviously there is sun, there is air and glaciers.
00:36Let's take water as an example.
00:38When water flows from the mountainous area due to melting of glaciers or due to rainfall,
00:43the water tries to disintegrate and weather the mountains on its way.
00:50The weathering agent is weathered.
00:52The material that it picks up, with the help of force, it carries it along.
00:57During that journey, the pebbles break on their way and convert into small pieces.
01:05Let's take a sand or silt combo.
01:07When sand or silt goes into the plain areas, in the case of flood,
01:11when the same water is deposited in the surrounding area, it forms a layer.
01:18Let's say that the first year comes, a layer is formed of that deposit,
01:22which was carried from that journey.
01:25So the first layer came, then the next year, the flood came, another layer came,
01:28then the third year, fourth year, fifth year.
01:31In the same way, this process continued for millions of years.
01:35So what happened?
01:37This upper layer pressed the lower layer.
01:40So by pressing, you will get a block of the lower layer, which will form a solid block.
01:46So basically, in this process, we saw how sediment makes a layer.
01:51And with the compaction of the layer and the cementation of the minerals inside it,
01:55that thing joins together and takes the form of a rock.
01:58This is how a rock is formed.
02:00We call it sedimentary rock.
02:02There are different types of T2.
02:04We have mechanical form sedimentary rock.
02:14We have second category, chemically formed sedimentary rock.
02:22And the third category is organic sedimentary rock.
02:31So as you can see from the name, mechanically formed sedimentary rock,
02:35means such rocks which are mechanically formed,
02:38like I gave you an example,
02:40when pressure was applied, then cementation force was applied,
02:42so such rocks were formed, which are mechanically formed sedimentary rocks.
02:45There are further types of these, such as adhesive rocks,
02:48which have more particles of sand,
02:50and agilious rocks, which have more particles of silt.
02:53Second, we have chemically formed sedimentary rock, which is a chemical solution.
02:57For example, we have a chemical solution of sodium chloride.
03:02It is a chemical solution of mango salt.
03:04So what happened is, by evaporation process, the water evaporated from it,
03:09and we have the remaining samples of rock at the bottom.
03:13So all the rock salts that we get,
03:15are in the form of chemically formed sedimentary rock.
03:19Even though, we have processed it,
03:21we have also collected salt from the oceans.
03:24But in the same way, the example of limestone is that,
03:26in limestone areas, especially when water flows,
03:30it absorbs the limestone,
03:32makes a chemical solution inside it.
03:34Then, after all, during the journey, when the water evaporates,
03:38again it becomes a limestone rock.
03:41So this is an example of chemically formed sedimentary rock.
03:43Similarly, we have organic sedimentary rock.
03:47So in organic sedimentary rock, basically we have the fauna and flora,
03:50you can say that the remains of animals,
03:52or the remains of plants,
03:55they become a part of the sedimentary rock.
03:57In that case, there are two types of rocks,
04:00calcareous sedimentary rock, and carbonaceous sedimentary rock.
04:03So in calcareous rock, basically,
04:05calcium is more,
04:08you can say that the marine animals,
04:10or animal skeletons,
04:12the part of their rocks,
04:14that is, the rocks are formed,
04:16they are called organic sedimentary rock,
04:18or calcareous rock.
04:20And the rocks, the plants,
04:22like coal, for example,
04:24under the surface of the earth,
04:26in the absence of oxygen,
04:28the plants are formed into coal,
04:30into rock coal.
04:32So that is the carbonaceous rock.
04:34So we have calcareous rock,
04:36organic calcareous rock,
04:38and carbonaceous rock.
04:40So students, I am going over the basic definitions,
04:42I am telling you the basics of sedimentary rock,
04:44I will tell you the basics.