Introduction to unconformity || stages and types

Unconformities:-
••••••••••••••••••••••••
An unconformity is a plane of discontinuity that two rock starta.

Unconformities are formed when there is break in sedimentation. This creates a gap in geological record.

It is an erosional surface that separates older rock from the younger rock.



Stages of formation of Unconformities:-
°°°°°°°°°°°′°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
1. formation of Older rocks.

2. Subareal erosion of older rocks.

3. Formation of younger succession of beds above the surface of erosion.






Types of Unconformity:-
°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
1. Angular unconformity

2. Disconformity

3. Local unconformity

4. Non conformity






Angular unconformity:-
••°°••°°••°°••°°••°°••°°••°°••°°
The rock bed on opposite sides of angular unconformity are not parallel.

If the bed beneath the erosional surface are folded or tilted , so that there is an angular relationship between the older and younger beds, this contact is called angular unconformity.


The altitude of the rock above and below the plane of discontinuity are differ from each other.

Here both the younger and older rocks are Sedimentary rock.





Disconformity:-
••°°••°°••°°••°°••°°
It is also known as parallel unconformity.

The rock beds present above and below the unconformity are parallel to each other.
there is no angular relationship.

The lower and upper series of beds are dip at the same amount and at the same direction.

This type of Unconformity found in sedimentay rock i.e. both the younger and older rocks are Sedimentary origin.




Local unconformity:-
••°°••°°••°°••°°••°°••°°••°°••°°
It is also known as non depositional unconformity.

This unconformity is also termed as diastem.

It is similar to disconformity but it is local in extent.

The rock difference between the younger and older rocks is very less.



Non conformity:-
••°°••°°••°°••°°••°°••°°
It is also known as heterolithic unconformity.

Here the older rocks are plutonic igneous rock but the younger rocks may be sedimentay rock or lava flow.

Here erosion must have occur to expose to plutonic igneous rock at the surface.







#unconformities #typesofunconformities #angular_unconformities #disconformity
#local_disconformity #non_conformity
#parallel_unconformity #non_depositional_unconformity
#heterolithic_unconformity #unconformity
#geology #12th_geology
#bsc_geology #12th_geology_odisha #JAC_geology
#geology_aspirant #Owais_videos









👉 join us


Telegram


https://t.me/GeologyAspirant



Instagram


https://www.instagram.com/geologyaspi...









Do like and share, if you are new to the channel then please subscribe to our channel and also press the bell icon to get new geology related updates.






Thank you (team geology aspirant)