Introduction to Earth sci.pdf

Overview of earth science- encompasses all sciences that seek to understand - Geology - study of earth - Oceanography- the study of the ocean - Meteorology- the study of the atmosphere and the processes that produce weather - astronomy- the study of the universe Geology...

Overview of earth science- encompasses all sciences that seek to understand - Geology - study of earth - Oceanography- the study of the ocean - Meteorology- the study of the atmosphere and the processes that produce weather - astronomy- the study of the universe Geology is usually divided into 2 broad areas Physical Geology - Examines the materials composing earth - Understands the processes beneath and upon its surfaces Historical Geology - Aims to understand the origin of earth and the development of the planet throughout its 4.5 billion year history Nebula Hypothesis - The nebula was composed mostly of hydrogen and helium - Nebula began to contract 5 billion years ago - Assumed a flat, disk shape with the protosun(pre-sun) at the center - Inner planets begin to form from metallic and rocky clumps - Larger outer planets began forming from fragments with a high percentage of ices. Earth's major spheres 1. Hydrosphere - Ocean is the most prominent feature of the hydrosphere - Is 71% of earth's surface - Holds about 97% of earth's water (includes fresh water in streams, lakes and glaciers. 2. Atmosphere - Thin, tenuous blanket of air - One half lies below 5.6 kilometers (3.5 miles) 3. Biosphere - Includes all life  4. Geosphere - Consists of the crust, mantle, and core Crust- the thin rocky outer layer of earth Mantle- the 2890 kilometer thick layer of earth below the crust Core- the innermost layer of earth, located beneath the mantle Lithosphere - is the strong, upper 100 km of the Earth. The lithosphere is the tectonic plate we talk about in plate tectonics. Asthenosphere - is the weak and easily deformed layer of the Earth that acts as a “lubricant” for the tectonic plates to slide over. Oceanic crust- thinner but denser Continental- Thicker but less dense Plate tectonics - Plate tectonics is the theory that proposes that Earth’s outer shell consists of individual plates that interact in various ways and thereby produce earthquakes, volcanoes, mountains, and Earth’s crust itself. Determining location Latitude - Is distance north or south of the equator, measured in degrees Longitude - Is distance east or west of the prime meridian, measured in degrees Topographic Maps - Represent earth's surface in 3 dimension, they show elevation, distance direction, and slope angles Contour lines - Lines on a topographic map that indicate an elevation Contour interval - Is the distance in elevation between adjacent contour lines A system is any size group of interacting parts that form a complex whole - Closed systems - are self contained (ex: a sealed water bottle, automobile cooling system,) - Open systems - allow both energy and and matter to flow in and out of the system ( ex: river system, human beings Sources of energy Sun - Drives external processes such as weather, ocean circulation and erosional processes Earth’s interior - Drives internal processes including volcanoes, earthquakes and mountain building Environment - Surrounds and influences organisms - Physical environment encompasses water, air soil and rock Hypothesis - Tentative or untested explanation Theory - Tested, confirmed, supported hypothesis 1. Collecting facts 2. Developing a hypothesis 3. Conducting experiments 4. Reexamining the hypothesis and accepting, modifying, or rejecting it