petroleum geology

[ there might be some errors in the text below]

porosity is of 2 types:-
bulk: The porosity calculated considering the total pore spaces.
effective: the porosity calculated considering the pores that can hold hydrocarbon.

The component that will occupy the pore depends upon the pore size

Sedimentary texture:-structure formed due to sedimentation. It is of two types:-
1)that forms on surface:- Depends on flow and deposional enviornment(also known as bed forms)[example:ripple marks]

2)that forms in beds:-current bedding. enourmous importance in studying the depositional history.

Sedimentary structures are used to know the paleocurrent flow.

most indian oils are generated from type-3 kerogens. type-3 kerogens are derived from terrestial organic matter.

Transgression—> flooding –effect–>ground water table also rises —>controls eroison–>sedimentation is less

Regression:- base level of eroison decreases, area available for deposition decreases.

During the last glacial period the sea level decreases about 138 metres. lot of shelf was exposed, the base level of erosion went down
so no deposition in vast area Because slope of shelf is very less. Such an kind of unconformity formed is known
as 1st order unconformity.

Primary migration:- low permiability rock, Fine grain rock.

secondary migration:- high permeability rock, coarse grain rock.

For any suggestions and questions please post comments.