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Environmental Science
Nick Eyles

Geology is derived from the Greek words Geo and logos which means the study of the Earth The first geological map was made 3000 yrs ago but the discipline of geology only started in the late 18 century because of the industrial revolution and needing large amounts of energy/minerals lead to creating new professions that study the earth called geologist William Smith made one of the first comprehensive geological maps of England (called the map that changed the world) that matched things in different areas with distinguishing features in 1815 and was called the father of English Geology. He also became the founding director of the geological survey of Canada In the late 17 century, they believed the earth was 6000 yrs old but now they believe its 4500 million years and was created by the changing physical environment of earth (moving continents) and extraterrestrial processes Alfred Wegner mad the idea continental drift and came up with a lot of evidence that the continents moved from a large land mass called Pangea meaning all of the lands 250 million years ago. Pangea was made of Godwana (S.A and Africa, Antarctica, Australia and India) while Laurasia made of N.A., Europe, and Asia) the evidence was the geological fit of S.A and Africa as well as similarities in rock types, fossils and structures. He noticed that in S.A., Africa, India, Antarctica, and Australia had almost identical late Paleozoic rocks and fossils. He saw glacial deposits on many continents and if it were to occur on all the separate continents as they are now, the climate must have been cold enough to surround the entire planet but there was no evidence for it. Also then the ice sheets must have spread from oceans to continents but this is impossible. Therefore this idea was. Wegner reconstructed old climate zones known as paleontology where glacial features indicate a cold climate near the North/South Pole while coral reefs indicate warm water near the equator, and cross bedded sandstones indicate ancient deserts 30 degrees north and south latitude. This idea is was rejected bcs didnt have a mechanism to explain how this happened because his best explanation was the combination of earths rotation and the gravitational forces that cause tides must lead to continental drift. This led to the development of plate tectonics theory by Tuzo Wilson in 1970. HE was the first person to do the degree of geophysics at Uof T and came up with the idea of transform faults which are major plate boundaries and an active chain of volcanoes that make islands like Hawaii and its called active volcanoes William Logan is known as Canadas premier scientist and made a revolutionary map or South Wales because he used cross-sections- a hypothetical vertical line through the land. What he also did is walk on food across Canada at that time made of Ontario and Quebec and made full descriptions of rocks, minerals and soils st making the 1 systematic layout of the geology of Canada Geology involves vastly greater amounts of time called deep time but some geological processes occur quickly like landslides and volcanic eruptions bcs they suddenly release stored energy. But other processes are slow and relentless and to a geologies rapidly means a few million years The earth is 4.55 billion years old but fossils show that complex animals have existed for 545 million years, reptiles 230 million years, dinosaurs went extinct 65 million years and humans existed for 3 million years Traditional geologists spent time in the field looking (prospecting) tell-tale signs of minerals. Exploration geologists-work for exploration companies looking for gold, silver and diamonds and try to get it to the market before others do. Geoscientists- explore and try to mitigate the effects of natural hazards and so there are a number of different types. Geochemists- work in labs and use high technology to analyze the chemistry of rocks and work with mineralogists/ petrologists that study minerals or the makeup and formation of rocks. Geophysists use technology in the field like boats and ships to study the physical conditions on or underneath the earth. Seismologists- study how to and mitigate earthquake activity and paleontologists- study the fossilized remains of ancient organisms. Glacial geologists- study landforms and sediments left behind from ice sheets while hydrogeologiests study how sediments contain and transmit water Geoscientists deal with info that is sensitive of financially significant like a piece of land that is contaminated by chemicals or mineral deposits. Also they are registered professionals and so the public relies on things they decide to do Environmental geoscientists- deal with finding and managing drinking water like ground water as well as dealing with wastes like radioactive largely because the world is becoming urbanized. To answer questions like if the land had radioactive chemicals they need to see underground using geophysical techniques and geochemical data that make 3D images of the arrangement of strata. Engineering geologists- work with civil engineers to provide info about substrates that form where buildings etc are going to be made because it can create problems about foundations geomaticians- collect, organize, analyze, and create images from spatial and geographic data available in digital form Boulders are not randomly dispersed through the till but rather occur in horizontal layers called pavements. SCIENTIFIC METHODS- Geologists are scientists that use the scientific method where they1. identify the problem then a methodology to collect data to solve the problem then 3.analuze/ interpret info using maps and computers to come up with a solution 4. Hypothesis- a theoretical explanation where the geologist is saying well I dont know the whole story but I think this is a good explanation and there are normally more than one answer to problems. Normally we make multiple hypotheses and reject many. 5.but the one that passes through repeated testing6. becomes a theory which has a good chance of being true Earth is old and in the solar system not as a sold body but also as oceans, atmosphere, and life, and these individual components interact to form the dynamic system called the earth system The universe was made from clumping of gas and debris after the Big Bang that occurred 15 billion years ago and there are many galaxies in this universe but the Milky Way has our solar system and earth that was made from gas and dust particles called nebula. The particles started contracting where the bulbous core started doing nuclear fusion and make our sun while the dust in the outer side made large rounded planets and smaller irregular shaped planetismals the process of making large bodies of matter through collision and gravitational attraction is called accretion The planets closed to the sun, Mercury, Venus, mars earth, and mars are small, dense and rocky terrestrial planets while the bigger Jupiter, Saturn, Uranus, and Pluto have low density called Jovian planets Heat made by accretion of debris and gravitational compression as well as the decay of radioactive isotopes allowed earth to melt such that heavier materials like iron and nickel went to the center and lighter materials like silica and oxygen came to the surface. This process of zonation of different particles is called differentiation Small solid particles of rock, metal, and ice orbiting sun is called meteoroids. When they enter earths atmosphere they become heated and light up due to friction called meteors or shooting stars but most break before hitting the earth. If they hit the earth they are called meteorites and normally 150/year are large enough to hit the earth. There are 3 major types, iron, stony iron, and stony meteorites which are the most common but hard to find since look like earth rock. Iron meteorites are rare but easier to find. Iron meteorites are mostly iron with small amounts of nickel. Stony iron is made of iron nickel alloy and silicate minerals in equal parts while stony meteorites- are made of silicate minerals and small amounts or iron nickel. 90% of stony meteorites (chondrites)have silicate grains called chondrules while the other 10% are anchondrites that lack chondrules which are made of olivine and proxyene The earths structure is differentiated, with a core- made of iron alloy, (iron, nickel, and silicon), the mantle is made of Fe-Mg silicates making a rock called periodotite and the crust is made of lighter rock called basalt and granite The movement of the mantle by convection currents moves the curst and upperpart of the mantle as large pieces called the lithospheric plates and they are moved over a week later called the astheosphere and this movement is a fundamental process for plate tectonics The earths atmosphere was made form water and gaseous elements being released during volcanic eruptions in a process called outgassing the oldest known sedimentary rock was 3.8 billion years old and the earths atmosphere was mostly CO2 due to volcanoes and rainwater and ocean water and the oxygen rich atmosphere was mad
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