Geology is classified as a complex science which has a various materials and interesting to learn. Generally, Geology is learning about the smallest component of the world called by Atom as well as learning about the continent, Ocean, Basin, Mountain range form, etc.
It is important to learn because necessaries are mostly gotten from the earth, like jewelry, household equipment, transportation and the energy material, such as Petroleum and coal. Additionally, people activities have a complex relation with the earth such as dike, bridge, and high building on the earth, or even supplying the mining the needs such petroleum and coal, which means people must dig the land up to get these mining materials. The tight relation of geology with civil technique and mining needs as sector of engineering might be the cause of the geology science development, up till now it has become a must-learning science not only by those who making the geology as the profession, but also people having a different profession which still have a tight relation with the earth.
By that rapid of human civilization development, where people really need mining materials such gold, coal, iron mine and petroleum as an energy source. Consequently, geology developed to be an exploration important key. It happened is because the people step up the supplying needs of mining materials. Recently, earth phenomenon happens more and more, either it is accordingly caused by the earth itself or human in supplying the mining material needs which is done without the earth base science in the surrounding environment. With that indication, geology then developed quickly.
Definition of Geology
Geology is derived from “Geo” which means earth, and “Logos” which means science. So Geology is science learning about earth with the existed content. In addition, it is learning about the characters and materials which form the earth, its structure, and the earth process and all about the earth development story since it was firstly formed up till now.
Geology has various materials; therefore, it is divided in to two materials category: Physical and Dynamic geology. Let’s see the following scheme which explains about a complex interaction and mutual influence between lithosphere as the most outside solid material of the earth with Atmosphere and hydrosphere which then creates Biosphere as a part of the earth where these 3 materials are jointly to create a live. Finally, this interaction causes the dynamic character of the world.
Concept and Law of Geology
It is urgent to know the concept and law of geology as a basic understanding of learning geology. Normally, it has been a parameter reference of geology science which eventually explains us about the concept of structure, regulations, and complex relation of boulder in place and time.
A. Uniformitarianism Doctrine
A geology science history began since 17 to 18 century with a popular doctrine, catastrophism. The followers believed that the earth formation surface and all lives on the earth formed and destroyed in a moment caused by an over catastrophe. James Hutton, a Scotsman as a modern geology father and physicist, in 1795 published the book “Theory of the Earth”. He initiated the popular doctrine, the uniformitarianism doctrine. This uniformitarianism is a modern geology basic concept which told that the now physic, chemistry, and biology laws are the same with the past conceptual laws.
This doctrine as more popular as “The present is the key to the past” since it, people realize that world changes accordingly, insufficiently. He interposed a superposition law which told that in the stabile level, a most bottom layer is the oldest Paleontology expert started to connect a particular fossil on its own level which has an absolute form called by a fossil index. A fossil index has been particularly used in identifying horizon and a relation of places.
B. Geology Basic Principle
Nicolas Steno (1665) was well recognized as the first man introducing geology basic principle which up to now is still used in the interpretation of a layer of sediment boulder. There are 3 most important geology basic principles; they are horizontality superposition and literal continuity.
The Horizontality is a position of the first sedimentation of a boulder layer.
The Superposition, in the normal condition, the most-under boulder layer is the first and the oldest formed boulder than other layers.
3. Lateral Continuity
A boulder layer will have a continue layer formation. The fancies conceptual changing will happen if only in boulder layer exists the character of physic, chemistry and biology concept, which is different one another.
C. Conformity and Unconformity
Conformity is a relation between one to another boulder layer and it has no gap of time of sedimentation. That it continuously happens.
Unconformity is a relation between one to another boulder layer and it is not continuously happen.
Disconformity is one of unconformity concepts. Where, one boulder layer to another has a relation but it is limited one particular gap of time where sedimentation does not happen.
Non-conformity is one of unconformity concepts where one boulder layer to another has a relation with a metamorphic boulder.
D. Transgression and Regression
Transgression, in sedimentology understanding is the speed degradation of a dike base which is faster than sediment supply.
Regression, in the sedimentology understanding is the speed degradation of a dike base which is lower than the sediment supply
E. Structure of Geology
Geology structure is the whole elements of the earth architecture which is caused by the earth endogen energy symptom; they are Joint, Fold, Fault and conformity. The explanation as follows;
Joint is a crackle of boulder which the boulder displacement still does not happen. Joint will definitely happen to every boulder kind. Properly, it is caused by tectonic and weathering. There are many kinds of Joints; they are Shrinkage Joint, Sheet Joint, Shear Joint, Systematic and Non-Systematic Joint.
In the early 1987, a Greek, Ragan stated that Fold is formation volume changing result from an element that is form curvature of the earth. Based on the axial surface and hinges line structure turns and Weiss classified this axial surface and hinges line into 7; they are Horizontal Normal, Plunging Normal, Horizontal inclined, Reclined, Vertical and Recumbent.
Fault is an exists crack with a clear placement. This placement can occure arround 15 millimeters to 100 millimeters. Fault can also occure in some boulders, with this placement caused, Fault will change the topography development, controlling air surface of the water, and finally breaking the boulder stratography. These are a lot of fault element elassifications. They are Net Slipe, Strike Slipe, Dip slipe, Rake, Throw, Heave, Hanging wall and foot Wall.
Twenhofel (Collison, 2006), has given the clear terms of the fault conformity with a basic of Ganesa. A basic of Ganesa is an environment sedimentation source. Particularly for land and sea sedimentation. In identifying it, Billings (1976), explained this fault by making fault classification which is used the existed basic, the Unconformity may happen in a moment caused by 2 causal factors, they are;
a. There is no sedimentation phenomenant but there is only denudasional.
b. It is limitation which separated the old and the young boulder because of the earth’s outer crust elevation.