Marine Geology

A.Y. 2014/2015
Lesson for
6
Max ECTS
48
Overall hours
Language
Italian
Learning objectives
Il corso si prefigge di fornire solide conoscenze di base su : a) metodi di indagine indiretti e diretti che si utilizzano in Geologia marina; b) principali caratteristiche della crosta oceanica e dei sedimenti; c) evoluzione degli oceani. La parte finale del corso è finalizzato all'analisi di alcuni esempi attraverso i quali gli studenti sono guidati ad acquisire capacità di lettura critica di lavori scientifici riguardanti ricostruzioni geodinamiche-paleoceanografiche basate su dati di geologia marina.

Course structure and Syllabus

Active edition
Yes
Responsible
Lessons: 48 hours
Professor: Erba Elisabetta
Syllabus
Introduction to Marine Geology: definition, objectives and historical background.
Methods of investigation: 1. INDIRECT (geophysical and oceanographic approaches). Acustics: propagation, distribution and velocity of sound. Controlling factors of sound velocity: solar radiation, distribution of temperature, salinity and density. Positioning and bathymetry. Instruments: ecosounders, Subbottom Profilers, Chirp, etc. Acustic sources. Seismic Survey. Bore-hole loggings. Synthetic sismograms. Integration between Geophysics and Geology. 2. DIRECT: observation (subs, submersibles, ROV). Sampling (dredgings, corings, deep-sea drillings from large platforms). Instruments and operations: gravity and piston corers, vibrocorer, BRIDGE rock drill, Box Corers, dredges, mechanic arms). Drilling systems (Joides Resolution).
Physiography: Continental platforms, Continental Rises, Abyssal Plains, Submarine Canyons. Oceanic Throughs. Ridge System. Atolls, Guyots and Seamounts, Plateaus.
Introductory Oceanography: Atmospheric Circulation (wind patterns). Oceanic Circulation: thermoaline (chemico-physical characters of water masses), upwellings and downwellings, current sytems. Control of circulation on sedimentation and climate.
Sedimentation: Terrigenous sediments, Biogenic carbonate and siliceous sediments; Authigenic and hydrotermal deposits; Volcanogenic sediments; Coral reefs. Rates of sediment accumulation.
Oceanic Crust and its evolution. Mid-ocean Ridges and their geodynamic significance. Magnetic lineations, spreading velocity. Thermal Subsidence. Distribution of earthquakes and volcanism.
Birth of an ocean. Margins: passive, active, and transform. Convergence and subduction. Examples of active margins. Volcanic and magmatic arcs. Evolutionary stages of modern oceans.
Geomagnetism and paleomagnetism: Introduction, magnetic dipole, reversals of Earth's magnetic field (magnetic anomalies). Principles of magnetostratigraphy (magnetic chrons, construction of a paleomagnetic scale). Paleolatitudes and paleoceanography: examples.
Geodynamic evolution of the oceans from Jurassic to present. Plate motions and Paleoceanographic implications: examples
Lesson period
Second semester
Lesson period
Second semester
Assessment methods
Esame
Assessment result
voto verbalizzato in trentesimi
Professor(s)