A rock is lustrous and shiny if it has Dolomite Crystall which is lustrous in front of the sun. Formation are some kinds of rocks which can be seperated due to some general principles like age, lithology and fossils, and when you separate them, you give them a name like: Sargalu, Surdash, Nawkalakan, Berserin, Bexma...etc

1. 2019
Soran University
Faculty of Engineering
Petroleum engineering department
Field trip Report
Prepared by : Raboon Redar Supervised by : Mr. Arkan
Mansur Nidhal

2. Contents
Introduction...................................................................................................... 1
Discussion....................................................................................................(1-2)
Source and reservoir rock.................................................................................. 3
Conclusion......................................................................................................... 4
References........................................................................................................ 4

3. 1
Introduction
Sedimentary rocks Petroleum may occurin any porous rock, but it is usually found
in sedimentary rocks such as sandstone or limestone. Sandstones, because of the
inherent porosity between their grains, often become excellent reservoirs for oil or
natural gas. (D.L. Baars, n.d.)
Discussion
A rock is lustrous and shiny if it has Dolomite Crystall which is lustrous in front of
the sun. Formation are some kinds of rocks which can be seperated due to some
general principles like age, lithology and fossils, and when you separate them, you
give them a name. Sargalu is a village in dukan near surdash where you can see a
type of rock very clearly which is nearly 115 meters, but in soranits 75 meters high.
You can seethis type ofrockvery clearly in sargalu that's why they named it sargalu.
If you find any types of rocks very clearly in any place, you name it as the place's
name like nawkalakan (on the way of choman) and barsrin. Thosetypes of rocks are
generally from the Jurassic age (200 - 150 million years before now). Sargalu is a
sediment in the age of the middle Jurassic and was beneath a (3000 - 4000) km sea.
We know that becauseof someliving things and animals which have lived there and
can only live beneath this range and also with the help of isotope which can choose
the rock's elements and living environment. Sargalu consists of limestone, chert,
shale and dolomite. The white grains that shine, are called saccharoidal dolomite
which seems like sugar. Lines are liquid poured calcium, just like permeability. This
rockseems black because it consists of Bitumen which is a black viscous mixture of

4. 2
hydrocarbons and wherever we have hydrocarbon it can help to create oil. To find
out what type is the rock, you can break it, shell and marble are easily breakable but
dolomite, limestone and sandstone are harder that dolomite is also harder than
limestone. That's a simple way to find out the the rock type but not accurate, that's
why you need to interact it with HCl, if HCl effected the rock and reacted clearly,
it's limestone. If its reaction wasn'tclear orreacted a little bit it's dolomitic limestone.
If it had no reaction, then it's dolomite. That's howyou differ dolomite and limestone.
You can also smell it, the smell of hydrocarbons is yucky and that shows the
existence of hydrocarbon and oil. Sargalu rock reacts with HCl so it consists of
limestone. Shale has fissility that refers to the propertyof rocks to split along planes
of weakness into thin sheets. If a rock reacts with HCl, that means it consists of
dolomite, and if it seems black, it's organic, so you can call it organic
dolomite/dolostone. Sargalu and nawkalan are 2 of the most Important sources and
reservoirs of oil industry in Kurdistan. Oil comes from a source (a rock that is
organic like a shell or limestone) and enters a reservoir which has a good fracture
porosity and permeability, but if there's no caprock cell (evaporite, saltrock and
shell) above the source and reservoir to avoid the oil coming to the earth's surface,
you can't benefit from it like in (bexma). These organic rocks from the mountains of
soran are (2000 - 3000) meters under the earth's surface in Kirkuk. Tectonic plates
have affected these mountains to compress upwards, unlike the planes of Kirkuk
where tectonic plates were weak. Anywhere we have hydrocarbon, is an oil source,
anywhere we have fracture, porosity and permeability, is a reservoir, no matter what
kind of rock it is. Limestone can be a sourceor a reservoir, the best source of oil in
Iraq is (Mashrf) which is a limestone in Basra. You can't burn organic rocks that are
above the earth's surface because their organic structure has been washed out by
acidic rains. Geophysics can realize were oil, gas, and water are under the earth's
surface by sending seismic waves which can travel to the liquid and come back by

5. 3
different speeds because of their difference in density. Clay has super fine particles
that cling together and prohibit water and nutrient movement, while sand has course
particles which allow water and nutrients to leach too rapidly. There actually is one
more classification called silt which has particles sized between clay and sand.
Source andreservoir rock
Shale: The most typical source rock is shale which is a fine grain rock that comes
mostly from clay. Another example of source rock is limestone which is composed
of calcite CaCO3, the main building element in sea shells. (Levorsen, 1954)
Sandstone and Limestone are two Sedimentary Rocks which are used as a reservoir
rock. A good reservoir rock must be a good porous, permeable, and contains
Hydrocarbon as well.
Dolomite also serves as an oil and gas reservoir rock. During the conversion of
calcite to dolomite, a volume reduction occurs. This can producepore spaces in the
rockthat can be filled with oil ornatural gas that migrate in as they are released from
other rockunits. This makes the dolomite a reservoir rock and a target of oil and gas
drilling. (King, n.d.)

6. 4
Conclusion
As a petroleum engineer, when you try to understand and research rock types, their
hardnesses and any other organic compounds,you can understand that geology is
the science. By all counts, and with proven results, it is no wonder that Geology is
the most important science that is needed for becoming a skillful petroleum
engineer.
References
D.L. Baars, W. L. W. D. W. S. a. E. A. B., n.d. KansasGeological Survey.
[Online]
Available at: http://www.kgs.ku.edu/Publications/Oil/primer03.html
[Accessed april 2001].
King, H. M., n.d. geology. [Online]
Available at: https://geology.com/minerals/dolomite.shtml
Levorsen, A. I., 1954. large stanford. [Online]
Available at: http://large.stanford.edu/courses/2013/ph240/malyshev2/