Geology
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Volcanic materials
⚒️🔥 Volcanic materials 🔥⚒️ When volcanoes erupt, solid rock debris, molten materials (magma) and gases come out. ♦️️ rock debris: As a result of volcanic eruptions, solid rock debris of various types and sizes usually emerges in the initial period of a volcanic eruption. The rock debris is derived fRead more
⚒️🔥 Volcanic materials 🔥⚒️
When volcanoes erupt, solid rock debris, molten materials (magma) and gases come out.
♦️️ rock debris:
As a result of volcanic eruptions, solid rock debris of various types and sizes usually emerges in the initial period of a volcanic eruption. The rock debris is derived from the hardened crust that is extracted from the walls of the neck as a result of the strong and violent push of lava and gaseous materials emanating from magma. Rock debris is composed of materials of different sizes, including rock blocks, shells and embers, sand and volcanic dust.
♦️️ Gases:
Water vapor gases emerge from volcanoes during their activity, and it emanates in great quantities, forming huge clouds in which dust and other gases mix with it. These vapors condense, causing heavy rains to fall in the vicinity of the volcano. The explosions and rain are accompanied by the occurrence of electric lights that arise from the friction of volcanic ash granules with each other and as a result of air disturbances, except for the extremely hot water fumes, the volcano emits multiple gases, the most important of which are hydrogen, chlorine, sulfur compounds, nitrogen compounds, carbon compounds and oxygen.
♦️️ Lava:
They are liquid masses ejected by volcanoes, with a temperature between 800°C and 1200°C. The lava emanates from the crater of the volcano, as well as through the cracks and fractures in the sides of the volcanic cone, those fractures that are created by the explosions and the pressure of the magma masses.
Light lava:
This is characterized by the bone of its viscosity, and therefore it is slow flowing, like the lava that emanated from the Pelly volcano (in the Martinique Islands in the Caribbean) in 1902. It was so thick and sticky that it was unable to move, and it began to accumulate and rise, forming a tower above the crater, with a height of about 300 meters. Then, soon after that, it was broken and shattered as a result of the explosions caused by the exit of gases.
⚒ Dark heavy lava:
It is basaltic lava, and it is characterized by being highly liquid and mobile, and it flows in the form of streams on the slopes of the volcano, and when this lava emerges through large fractures, it spreads over huge areas forming spacious plateaus, such as the Abyssinian Plateau and the Deccan Plateau in India and the Columbia Plateau in North America.
🔥️ Volcanic materials
🔹️Volcanic Solids:
The parts that make up volcanic rocks are:
⚒Volcanic ejecta:
It is a frozen magma and lava ejected to the surface.
⚒ Pumice rock:
It is a silicate foam that is evaporated by gases.
⚒Volcanic ash:
It results from the fragmentation and scattering of the frozen magma summit in the neck of the volcano under the influence of pressure and steam, and it hardens quickly.
🔹️Liquid volcanic materials magma and lava (lava):
It consists of liquid materials from the lava that flows burning from the crater to great distances sometimes, and the extent of lava liquidity is subject to several factors. Such as the slope of the earth, the nature of magma and lava (viscous or fluid) and the viscosity ratio depends on the percentage of silica, and on the strength of the volcano
Gaseous volcanic materials:
See lessAmong the most important gases emitted from volcanoes are:
⚒ water vapor
⚒ Hydrocarbon compounds
⚒ sulfur dioxide
What is difference between granite and basalt
Differences between basalt and granite Although there are some similarities between basalt and granite, there are also significant differences between these two rock types. Basalt is volcanic, or extrusive, forming at the surface, while granite is plutonic, or intrusive, forming beneath the sRead more
Differences between basalt and granite
Although there are some similarities between basalt and granite, there are also significant differences between these two rock types.
Basalt is volcanic, or extrusive, forming at the surface, while granite is plutonic, or intrusive, forming beneath the surface.
Basalt is mafic while granite is felsic
Basalt is common on both Earth and other Solar System bodies such as the Moon and Mars while granite is only common on Earth and rare elsewhere in the Solar System
Basalt can form in a few days to months, whereas granite plutons can take millions of years to cool and harden.
Basalt is more common in oceanic crust while granite is more common in continental crust.
See lessWhat type of volcano makes granite?
Rhyolite. Rhyolite magma cooling underground forms granite. Granite has large interlocking crystals that can be easily seen if you hold the rock at arm's length. Rhyolite is associated supervolcanoes and explosive volcanic eruptions that create calderas.
Rhyolite. Rhyolite magma cooling underground forms granite. Granite has large interlocking crystals that can be easily seen if you hold the rock at arm’s length. Rhyolite is associated supervolcanoes and explosive volcanic eruptions that create calderas.
See lessWho is the father of Geology?
Hutton was the first to propose: That planet operated a Rock Cycle powered by its internal heat, That igneous rocks like granite were intrusive, having been injected into older rocks whilst molten, That natural processes would have operated in the distant past at the same rates as obsRead more
Hutton was the first to propose:
Honourable Mentions to:
Nicolas Steno – Father of Stratigraphy (law of superposition, law of original horizontality, law of cross-cutting relationships, and law of lateral continuity.)
William “Strata” Smith – Father of English Geology (Law of Faunal Succession; “Map that changed the World”.
Arthur Holmes – Father of Geochronology (first radiometric dating of earth materials).
See lessWhat are the branches of geology?
Branches of geology focused on natural resources Most geology careers involve the extraction of natural resources from the surface. This is where geologists relate rock types and landforms in a specific environment. For example, petrology uses mineralogy and rock types to understand geological formaRead more
Branches of geology focused on natural resources
Most geology careers involve the extraction of natural resources from the surface. This is where geologists relate rock types and landforms in a specific environment.
For example, petrology uses mineralogy and rock types to understand geological formations from drilling. In addition, they study the chemical properties and how atoms are arranged.
Soils are also considered a natural resource for agriculture production. Agronomy, edaphology and pomology are specific to soil science and how food grows or is cultivated.
PETROLOGY – How types of rocks (igneous, metamorphic, and sedimentary petrology) form in their specific environment.
MINERALOGY – How chemical and crystalline structures in minerals are composed.
GEMOLOGY – How natural and artificial gems are identified and evaluated.
CRYSTALLOGRAPHY – How atoms are arranged and bonded in crystalline solids.
SOIL SCIENCES – How soils relate as a natural resource including their formation factors, classification, physical, chemical and fertility properties.
PEDOLOGY – How soils are classified based on their biological, physical and chemical properties.
EDAPHOLOGY – How soils influence plant growth and living things.
AGRONOMY/AGROLOGY – How the field of agriculture involves science such as crop production, biotechnology and soil science.
HYDROGEOLOGY – How groundwater is transported and is distributed in the soil, rock and Earth’s crust.
POMOLOGY – How fruits grow and are cultivated.
Sedimentology understands weathering, transportation and deposition
Sedimentology looks at the processes of how sediments deposit. For example, sedimentology is concerned with erosion, weathering, transportation, and deposition of sediments.
One of the processes that understands the erosion, movement and deposition of sediments is from glaciers. Specifically, glaciology studies glaciers and how they shape the landforms.
Likewise, surficial geology examines sediments overlying bedrock such as during a glacial retreat. Finally, beneath the regolith is the intact, solid rock that bedrock geology is concerned with.
SEDIMENTOLOGY – How sand, silt and clay are deposited and the processes that act on it.
SURFICIAL GEOLOGY – How surface sediment (till, gravel, sand, clay, etc) overlying bedrock was formed such as during glacial retreat or in lakes associated in these periods.
GLACIOLOGY – How ice and glacial deposits have reconstructed landforms as well as how existing (polar) glaciers behave and are distributed.
GEOPHYSICS – How physical processes and properties relate to Earth and its surrounding space.
BEDROCK GEOLOGY – How the intact, solid rock beneath surficial sediments formed including age (stratigraphic sequences), morphology and rock properties (folds, faults, fractures).
LITHOLOGY – How rocks are classified based on their physical and chemical properties.
Topography studies land forms and their processes
Topography also plays an important in geology. Of all the branches of geology, topography examines the physical features that are distributed on the landscape.
For example, orography focuses on topographic relief and how mountains are distributed. Without plate tectonics which is a focal point in geology, mountain building would have not taken place.
Finally, hypsometry measures the height and depth of physical features from the mean sea level. Geologists use hypsometry to understand the profile of Earth and landscape evolution.
OROGRAPHY – How topographic relief in mountains are distributed in nature.
See lessTOPOGRAPHY – How physical features (natural and artificial) are arranged on the landscape.
HYPSOMETRY – How height and depth of physical features are measured land from mean sea level.
What is Geology definition ?
its broadest sense, geology is the study of Earth — its interior and its exterior surface, the rocks and other materials that are around us, the processes that have resulted in the formation of those materials, the water that flows over the surface and lies underground, the changes that have taken pRead more
its broadest sense, geology is the study of Earth — its interior and its exterior surface, the rocks and other materials that are around us, the processes that have resulted in the formation of those materials, the water that flows over the surface and lies underground, the changes that have taken place over the vastness of geological time, and the changes that we can anticipate will take place in the near future. Geology is a science, meaning that we use deductive reasoning and scientific methods (see Box 1.1) to understand geological problems. It is, arguably, the most integrated of all of the sciences because it involves the understanding and application of all of the other sciences: physics, chemistry, biology, mathematics, astronomy, and others. But unlike most of the other sciences, geology has an extra dimension, that of time — deep time — billions of years of it. Geologists study the evidence that they see around them, but in most cases, they are observing the results of processes that happened thousands, millions, and even billions of years in the past. Those were processes that took place at incredibly slow rates — millimetres per year to centimetres per year — but because of the amount of time available, they produced massive results.
Geology is displayed on a grand scale in mountainous regions, perhaps nowhere better than the Rocky Mountains in Canada (Figure 1.1). The peak on the right is Rearguard Mountain, which is a few kilometres northeast of Mount Robson, the tallest peak in the Canadian Rockies (3,954 m). The large glacier in the middle of the photo is the Robson Glacier. The river flowing from Robson Glacier drains into Berg Lake in the bottom right. There are many geological features portrayed here. The sedimentary rock that these mountains are made of formed in ocean water over 500 million years ago. A few hundred million years later, these beds were pushed east for tens to hundreds of kilometres by tectonic plate convergence and also pushed up to thousands of metres above sea level. Over the past two million years this area — like most of the rest of Canada — has been repeatedly glaciated, and the erosional effects of those glaciations are obvious. The Robson Glacier is now only a small remnant of its size during the Little Ice Age of the 15th to 18th centuries, as shown by the distinctive line on the slope on the left. Like almost all other glaciers in the world, it is now receding even more rapidly because of human-caused climate change.
Photograph of Rearguard Mt. and Robson Glacier in the Rocky Mountains of British Columbia [SE]
Figure 1.1 Rearguard Mountain and Robson Glacier in the Rocky Mountains of British Columbia [SE]
Geology is also about understanding the evolution of life on Earth; about discovering resources such as metals and energy; about recognizing and minimizing the environmental implications of our use of those resources; and about learning how to mitigate the hazards related to earthquakes, volcanic eruptions, and slope failures. All of these aspects of geology, and many more, are covered in this textbook.
See lessWhat is the study of geology?
Geology is the study of the earth (geo means earth, and ology means study of). This is a very simple definition for something so complex. Geology involves studying the materials that make up the earth, the features and structures found on Earth as well as the processes that act upon them. Geology alRead more
Geology is the study of the earth (geo means earth, and ology means study of). This is a very simple definition for something so complex. Geology involves studying the materials that make up the earth, the features and structures found on Earth as well as the processes that act upon them. Geology also deals with the study of the history of all life that’s ever lived on or is living on the earth now. Studying how life and our planet have changed over time is an important part of geology.
See less