NIGB21026U Volcanoes, Magmas and Their Geochemistry

Volume 2023/2024
Education

BSc Programme in Geology-Geoscience

Content

This course focuses on magma-generation processes in the Earth's mantle and crust, the evolution of magmas by fractional crystallization in magma chambers in the crust, eruption processes, volcanic rocks and volcano formation. Students learn to use tools such as phase diagrams, classification diagrams, major and trace elements and petrological / petrographic analyses of hand samples and thin sections to describe magmatic evolution and the magma-generation processes. The course is structured around magma generation and volcanism in various tectonic settings.

The course begins with a field trip to a volcanic area in conjunction with the course "Dynamic stratigraphy - sediments in time and space". In the exercises, we will work with material from the field trip and this will result in a combined report for the field trip and exercises.

The aim of the course is for students to gain a basic understanding of the dynamics and geochemistry of the mantle and crust, and how these reservoirs formed throughout Earth history by magmatic and other physical and chemical processes.

Learning Outcome

Knowledge:

• know the mineralogy and texture of the most common igneous rocks and their geochemical and mineralogical compositional variation;

• know the basic structure of the crust with regards to igneous rocks, the definition of lithosphere and asthenosphere, and the variation of pressure and temperature through these;

• know the major tectonic settings where magmas are produced and volcanoes form, and how these tectonic settings influence magmatism;

• know the principles of formation and evolution of magma by mantle and crustal melting and fractional crystallization in the crust;

• know the physical properties of a variety of magmas, and how these influence volcanic processes, volcanic morphologies, volcanic rocks and the behaviour of magma;

• knowledge of the geochemistry of selected trace elements during mineral-melt equilibria and their behavior in different tectonic environments and magmatic processes

Skills:

• describe the structure and dynamics of the Earth with special emphasis on the upper mantle and the lithosphere;

• describe and classify igneous rocks according to mineralogy, texture and chemical composition;

• explain the basic conditions of formation, transport and crystallization of magma, (including the associated distribution of elements);

• explain rock formation based on the properties of silicate melts and crystal melt equilibria (magma physics and chemistry, phase diagrams);

• give an account of basic volcanic and plutonic processes, their relation to overall plate tectonic processes, as well as the principle structure of plutonic and volcanic complexes;

• be able to recognize the most common types of volcanic and plutonic rocks as well as describe and interpret their interrelationships in the field

 

Compentencies:

• relate igneous rocks to plate tectonic environments;

• relate igneous rocks to a presumed igneous evolutionary sequence;

• interpret volcanic rocks in relation to eruption type and magmatic composition;

• account for the presence of igneous rocks in the crust and thus the igneous structure of the crust;

• numerically model the chemical evolution of magmas by fractional crystallization.

Please see Absalon.

In order to follow teaching, an academic level corresponding to the BSc geology-geoscience education's compulsory courses of 1st year (i.e. corresponding to 60 ECTS) is recommended.
Teaching takes place through lectures, exercises and an initial field trip in Southern Europe. The teaching plan can be found on the course website at Absalon. A compulsory written report is prepared on the background of materials and observations from the field trip and the practical exercises.
  • Category
  • Hours
  • Lectures
  • 21
  • Preparation
  • 92
  • Practical exercises
  • 21
  • Field Work
  • 72
  • Total
  • 206
Written
Oral
Continuous feedback during the course of the semester
Feedback by final exam (In addition to the grade)
Credit
7,5 ECTS
Type of assessment
Written assignment, Ongoing
Oral examination, 20 minutes
Type of assessment details
The written assignment is prepared during the course and handed in after the 6th teaching week. At the oral exam, the student draws a question and is examined without preparation. The written assignment is worth 20% of the final grade and the oral exam 80 %. Students must pass both the written and oral exams to pass the course.
Aid
Without aids
Marking scale
7-point grading scale
Censorship form
No external censorship
Several internal examiners
Re-exam

Identical to ordinary examination.

Students who have not submitted the written assignment must submit it no later than 1 week before the re-examination. Students who have submitted a written assignment, but failed to pass the exam must submit an revised assignment no later than 1 week before the re-examination. 

Criteria for exam assesment

See learning outcome.