Petroleum Exploration and Geological Studies
Pressure and Temperature
To convert these fossils into hydrocarbons, high temperatures and pressures are needed. This temperature and pressure will change the chemical bonds of carbon in the rock to flatten the hydrocarbons.
Migration
Hydrocarbons that have been formed from a process above must be able to move to a place where hydrocarbons have economic value to be produced. In the source rock itself, it can be said that it is not possible to be exploited because hydrocarbons there do not accumulate and cannot flow. So this stage is very important to determine the possibility of exploitation of the hydrocarbons.
Reservoir
Rock which is a container for hydrocarbons which is a collection of the migration process. These reservoirs are generally sandstone and carbonate rocks, because these two rock types have pores large enough to store hydrocarbons. Reservoirs are so important because in this rock petroleum is produced.
Petroleum exploration
Traps
It's so important that a reservoir is protected by rock traps. The goal is that the hydrocarbons in the reservoir accumulate in that place alone. If this trap does not exist, hydrocarbons can flow to other places, which means the economy will be reduced or not at all. Traps in hydrocarbons are divided into two namely stratigraphic traps and structural traps.
Geological studies are regional studies, if regionally it is not possible to obtain hydrocarbons then there is no point in continuing.
If all of the above criteria can be met then the area may have the potential for oil or natural gas. Meanwhile, to determine whether or not economical further studies are needed relating to the physical properties of rocks. Then the rock research will continue in the next step.
Geological studies are regional studies, if regionally it is not possible to obtain hydrocarbons then there is no point in continuing. If all of the above criteria are met then the area is likely to have the potential for oil or natural gas.
Meanwhile, to determine whether or not economical further studies are needed relating to the physical properties of rocks. Then the research continues in the next step.
Geophysical Study
After the regional study using the geological method is carried out, and the results identify the hydrocarbon potential, the next step is the geophysical study.
At this stage special methods are used to obtain more accurate data to ascertain the presence of hydrocarbons and their potential for exploitation. The data generated from measurements, which is a reflection of the conditions and properties of rocks in the earth.
It is important to know whether these rocks have properties as source rocks, reservoirs, and trap rocks or only rocks that are not important in terms of hydrocarbons. These methods use physical principles that are used as engineering applications. These methods are:
Seismic exploration
This is an exploration carried out before drilling. His studies cover a very wide area. from the results of this study will get an overview of rock layers in the earth.
Resistivity data
The basic principle is that every porous rock will be filled with fluid. This fluid can be water, gas or oil. Differentiating the fluid content in rocks one of them by using the resistance properties that exist in the fluid. Fulida iar has a lower resistance value than oil, as well as an oil resistance value lower than gas.
Porosity data
Specific Gravity Data
Data is retrieved using a logging tool using radioactive material that emits gamma rays. The reflection from this ray will describe the specific gravity of the rock. We can compare if a rock pore containing water with rocks containing hydrocarbons will have a different specific gravity.