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EENS 1110. This page last updated on 01-Dec-2017. Physical Geology - The nature of the Earth; development of its surficial features; and the results of the interaction of chemical, physical, and biological factors on the planet. This course requires co-registration in Earth & Environmental Sciences 1115, Physical Geology Laboratory.
- Metamorphic Rocks
Note that diagenesis and weathering are also a changes in...
- Mineral Resources
Mineral Resources. Almost all Earth materials are used by...
- Groundwater
Tulane University: Prof. Stephen A. Nelson. Groundwater ....
- Introduction
Tulane University: Prof. Stephen A. Nelson: Introduction and...
- Ch 17 - Streams
Tulane University: Prof. Stephen A. Nelson. Streams and...
- Sedimentary Rocks
The formation of a clastic sediment and sedimentary rocks...
- Energy Resources
Tulane University: Prof. Stephen A. Nelson: Energy Resources...
- Glaciers and Glaciation
Tulane University: Prof. Stephen A. Nelson: Glaciers and...
- Metamorphic Rocks
All page breaks should occur correctly. If your web browser has the proper plug-in installed, clicking on the PDF will bring the file into your web browser from which you can then print the notes. If the plug-ins are not installed, your web browser will either attempt to download the PDF files or offer to send you to the Adobe web site to ...
August 28, 2017 - For this course you will need to know the chemical formula of the common minerals as listed HERE . I recommend you print the PDF version of this file and get started right away. September 18, 2017 - A revised version of the syllabus is now posted. This was necessary because the first day of class was cancelled.
- Petrology & Petrography
- Introduction to Igneous Rocks
- Gases in Magmas
- Plutons
- Volcanic Eruptions
- Explosive Eruptions
- Nonexplosive Eruptions
- Volcanic Landforms
- Tephra Cones (also called Cinder Cones)
- Maars
- Lava Domes (also called Volcanic Domes)
- Textures of Igneous Rocks
Petrology - The branch of geology dealing with the origin, occurrence, structure, and history of rocks. Petrography - The branch of geology dealing with the description and systematic classification of rocks, especially by microscopic examination of thin sections. Petrography is a subfield of Petrology. In this course, most of the lecture material ...
An igneous rock is any crystalline or glassy rock that forms from cooling of a magma. A magma consists mostly of liquid rock matter, but may contain crystals of various minerals, and may contain a gas phase that may be dissolved in the liquid or may be present as a separate gas phase. Magma can cool to form an igneous rock either on the surface of ...
At depth in the Earth nearly all magmas contain gas dissolved in the liquid, but the gas forms a separate vapor phase when pressure is decreased as magma rises toward the surface. This is similar to carbonated beverages which are bottled at high pressure. The high pressure keeps the gas in solution in the liquid, but when pressure is decreased, li...
Plutons are generally much larger intrusive bodies that have intruded much deeper in the crust. Although they may show sharp contacts with the surrounding rocks into which they intruded, at deeper levels in the crust the contacts are often gradational. Lopoliths are relatively small plutons that usually show a concave downward upper surface. ...
In general, magmas that are generated deep within the Earth begin to rise because they are less dense than the surrounding solid rocks. As they rise they may encounter a depth or pressure where the dissolved gas no longer can be held in solution in the magma, and the gas begins to form a separate phase (i.e. it makes bubbles just like in a bottle o...
Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas). z Explosive bursting of bubbles will fragment the magma into clots of liquid that will cool as they fall through the air. These solid particles become pyroclasts (meaning - hot fragments) and tephra or volcanic ash, which refer to sand- sized o...
Non explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas). If the viscosity is low, nonexplosive eruptions usually begin with fire fountains due to release of dissolved gases. Lava flows are produced on the surface, and these run like liquids down slope, along the lowest areas they can find. Lava...
somewhat steeper lower slopes (about 10o). Shield volcanoes are composed almost entirely of thin lava flows built up over a central vent. Most shields are formed by low viscosity basaltic magma that flows easily down slope away form a summit vent. The low viscosity of the magma allows the lava to travel down slope on a gentle slope, but as it coo...
Tephra cones are small volume cones consisting predominantly of tephra that result from strombolian eruptions. They usually consist of basaltic to andesitic material. They are actually fall deposits that are built surrounding the eruptive vent. Slopes of the cones are controlled by the angle of repose (angle of stable slope for loose unconsolidate...
z Maars result from phreatic or phreatomagmatic activity, wherein magma heats up water in the groundwater system, pressure builds as the water to turns to steam, and then the water and preexisting rock (and some new magma if the eruption is phreatomagmatic) are blasted out of the ground to form a tephra cone with gentle slopes. Parts of the crater ...
Volcanic Domes result from the extrusion of highly viscous, gas poor andesitic and rhyolitic lava. Since the viscosity is so high, the lava does not flow away from the vent, but instead piles up over the vent. Blocks of nearly solid lava break off the outer surface of the dome and roll done its flanks to form a breccia around the margins of dome...
The main factor that determines the texture of an igneous rock is the cooling rate (dT/dt) Other factors involved are: The diffusion rate - the rate at which atoms or molecules can move (diffuse) through the liquid. The rate of nucleation of new crystals - the rate at which enough of the chemical constituents of a crystal can come together in one p...
Plate Tectonics is a theory developed in the late 1960s, to explain how the outer layers of the Earth move and deform. The theory has caused a revolution in the way we think about the Earth. Since the development of the theory, geologists have had to reexamine almost every aspect of Geology. Plate tectonics has proven to be so useful that it ...
Note that diagenesis and weathering are also a changes in form that occur in rocks. In geology, however, we restrict diagenetic processes to those which occur at temperatures below 200 o C and pressures below about 300 MPa (MPa stands for Mega Pascals), this is equivalent to about 3,000 atmospheres of pressure.
Feb 27, 2011 · Oceans & Coasts EENS 1110 Physical Geology Tulane University Prof. Stephen A. Nelson Oceans and Coasts This page last updated on 09-Apr-2012 The Oceans Cover about 71% of the surface of the Earth. The greatest ocean depth of 11,035 m occurs in the Mariana. Solutions available.
