Geochronology

Geochronology is the science to determine the absolute age of rocks, fossils, and sediments, in a certain degree of uncertainty inherent in the methods used. Various types of age determination methods used by geologists to achieve this. 

Geochronology different application by biostratigraphy, which is the science of sedimentary rocks to put in a certain period geoogi through delineate, and benchmarking of Cataloging a collection of fossils of flora and fauna. Biostratigraphy not directly provide an absolute age determination of rocks, just place them in a given time interval in which the collection of these fossils have been known to have ever lived together. 

For example, with reference on the time scale of Geology, Permian and Over (Lopingian) lasted from 270.6 + / - 0.7 Ma to between approximately 250.1 + / - 0.4 Ma (Triassik oldest known) and 260.4 + / - 0.7 Ma (Lopingian youngest known) - a void in a collection of fossils that have determined its age, known to almost reach 10 Ma. While the biostratigraphic age of the Permian layers can show Lopingian, determining the actual age of these layers can be anywhere between 270 until 251 Ma. 

On the other hand, a determined old granite 259.5 + / - 0.5 Ma can reasonably called the "Permian", or more precisely, has mengintrusi in Permian time. 

Geochronology of science is the main tool used in the field Chronostratigraphy, which seeks to obtain absolute ages for all collection of fossils and determine the geologic history of Earth and the outer surface of the earth.

Geology Structure

Folded rock formations, a geological study of the subject structure

Geological structure is a study of three-dimensional distribution of rock body and its surface is flat or folded, and its internal structure.

Geologic structure that includes surface shape are also discussed in the study of geomorphology, and geology engineering metamorfisme. By studying the three-dimensional structure of rocks and regions, we can make conclusions about the tectonic history, geological environment in the past and the occurrence of deformation. This can be integrated in time using stratigraphical controls and Geochronology, to determine the time of forming the structure.

More formally stated as a branch of geology that relate to the geological process whereby a force has caused the transformation of form, composition, or the internal structure of rock into the shape, arrangement, or other internal interlaboratory composition.

Vulkanisme

Extrusive and intrusive (plutonic) is the same composition, but strong differences can be seen from the structure. These are formed due to its subduction (volcanic arc = darri typical subduction zone).

Types of volcano

· Shield volcano

· Composite volcano

· Dome volcano

Types of eruption

· Fissure

· Pyroclastic eruption (sediment grains)

A pyroclastic flow (Also Known scientifically as a pyroclastic density current) is a common and devastating result of certain explosive volcanic eruptions. The flows are fast-moving Currents of hot gas and rock (Known collectively as tephra), Which travel away from the volcano at speeds as great as Generally 700 km / h (450 mph).

1. Lava fountain

2. Eruptions of tephra (pyroclastic deposits of fine-grained = fine sand to clay)

This is used as a marker bed in determining the stratigraphy

Types of volcano based on size relatives ???????????????

Condition-related disasters or Geological Process

Here we review the processes of natural disasters is the primary geological process. Geological processes can be identified as an endogenous process (which works inside the Earth) and exogenous processes (who worked on the surface of the Earth).Endogenous process consists of:

1. Tectonic motion - causing an earthquake. Mengebabkan earthquake fault occurrence in the earth's crust. Earthquake shocks could spark Avalanche or Landslide as happened in Padang Pariaman. The fault that occurred on the seabed could trigger a tsunami (the process occurred at sea or hydrosphere), as happened when the earthquake December 26, 2004 in the Indian Ocean. Meanwhile, the landslide that occurred in the deep ocean trenches can also generate tsunami.
2. Magmatic - raises volcano - causing volcanic eruptions that cause pyroclastic flows or when there is Lava Hot participating crater lake collapsed. Then, deposition of sand on the slopes of the volcano when exposed to heavy rain (atmospheric processes) can lead to Lava flow, either hot or cold lava lava. Examples like that happened Mount Merapi Yogyakarta

Sedimentary structures

Sedimentary structures is a very broad sense, including the appearance of normal bedding including bedding kofigurasi appearance and / or modification of the bedding also caused both during the deposition process lasted well after the precipitation stops. Therefore it is important to first explain what exactly is meant by the bedding (bedding), so that will further clarify the limits of sediment structure.


Actually there has been no satisfactory bedding Definitively all parties, although in fact very broad terms the bedding was used in the descriptions of the Late Neogene sediments. Definitively the most widely used are those proposed by Otto (1938), a single is a unit of sedimentary layers deposited on the physical conditions remain constant. In line with the bedding itself was interpreted as a depositional surface areas caused by a change in sedimentation regime from time to time. These changes include:


A. Physical changes:

1. changes in the grain, including shape, size, orientation, packing and composition.
2. changes in various rocks, such as the limestone and marl.
3. Color change, although still having the same composition.

B. Chemical changes. In liquid solution carrying sediment changes in temperature, pressure, and concentration of ions will cause the bedding as well.


C. Biological processes. Differences in populations of organisms from time to time, will cause the bedding. Although no remains of dead organisms as fossils (eg worms) but the trail is likely to be found.

Geological Times Scale

Geological time scale used by geologists and scientists to explain time and relationships between events that occurred throughout the history of Earth. Table geological periods are shown on this page are adapted to time and nomenclature proposed by the International Commission on Stratigraphy, and uses a standard color code of the United States Geological Survey.Evidence from radiometric dating indicates that Earth was about 4570 million years. Geologic time the Earth organized into several units according to events that occurred in each period. Each day on the time scale is usually marked with large geological or paleontological events, such as mass extinctions. For example, the boundary between the Cretaceous and Paleogene extinction event is defined by baerbagai dinosaurs and marine species. Period of older, fossil relic that has no reliable estimate of age, defined by absolute age.

Geomorphology

Geomorphology is a scientific study of Earth's surface and poses that happened to him. Broadly speaking, associated with the landform (land form) eroded from the rock hard, the shape formed by the construction of rock debris, and sometimes by perolaku organisms in which they live. "Surface" (surface) should not be interpreted narrowly; must include also the most distant Earth's crust. Appearance of subsurface, especially in areas where limestone is very important cave system formed and is an integral part of geomorphology. The effects of erosion by water, wind, and ice, in collaboration with latitude, altitude and position relative to the water laiut. Can be said that each region with specific climatic characteristics also have their own views as a result of erosion that works differently to the existing geological structure. Incision of water on a hard limestone layer can form a permanent river flow and periodic, can also be a drainage channel that passes through the weak parts. To form a basin-basin on the yag eroded and left the higher part of the hard eroded. The size of this basin and the height can be several centimeters to several kilometers. Morphology of macro Below are some forms of surface karst morphology meters to kilometers in size:

* Swallow Holes: Locations where surface flow entirely or partially from a subsurface flow contained in the limestone. Swallow holes contained in the Polje is often called ponor. (Marjorie M. Sweeting, 1972). This

Mineralogy

Mineralogy is an earth science that focuses on chemical properties, crystal structure, and physical (including optical) of minerals. This study also covers the process of mineral formation and change.
Initially, the mineralogy is more focused on the classification system of rock-forming minerals. International Mineralogical Association is an organization whose members represent organizations that mineralogical experts from each country. Its activities include the naming of minerals mengelolaan (through the Commission of New Minerals and Mineral Names), location of known minerals, etc.. Up to 2004 there have been more than 4000 species of minerals that are recognized by the IMA. Of all these, the 150 can be classified as "general", 50 others "sometimes", and the rest is "rarely" to "extremely rare"
In recent years, due to the development view of experimental techniques (such as neutron defraksi) and existing computing capabilities have enabled atomic-scale simulation of the behavior of crystals with highly accurate, this science has evolved to encompass broader more general issues in the field of inorganic

Metamorphic Rocks

Metamorphic rocks are one of the main groups of rock that are the result of transformation or alteration of a rock type that has been there before, protolith, by a process called metamorfisme, which means "changing forms". Protolith subjected to heat (greater than 150 ° Celsius) and extreme pressure will experience physical changes and / or chemistry major. Protolith can form sedimentary rocks, igneous, or metamorphic rocks, others are older. Some examples are gneis metamorphic rock, slate, marble, and skist.
Metamorphic rocks make most of Earth's crust and are classified on the basis of texture and chemical composition and mineral (metamorphic facies) They formed far below the surface of the earth by the great stress from the rocks above and high pressures and temperatures. They are also formed by the intrusion of molten rock, called magma, into solid rock and is formed mainly at the contact between magma and high-temperature rocks.
Research metamorphic rocks (now exposed at the earth's surface caused by erosion and uplift) provides us valuable information about temperatures and pressures that occur deep within the earth's surface.