PDF of this syllabus, including Critical Concepts Meets: Tuesdays and Thursdays 11 am - 12:15 pm, Benson Earth Sciences 355 Course description: Examines the chemical, biological, geological, and physical processes affecting (and affected by) the chemistry of the oceans. Topics include: chemical speciation in seawater; the marine carbon cycle and its long-term control on atmospheric CO2; the large-scale interdependence of nutrient distributions and biological productivity; chemical tracers of ocean circulation; and the chemistry of marine sediments, including early diagenesis. This will be a lecture course. The required textbook is Ocean Biogeochemical Dynamics by Sarmiento and Gruber. This book will be supplemented by reserve readings from Volume 6 of Treatise on Geochemistry and Schulz and Zabel's Marine Geochemistry. Sarmiento and Gruber is not carried by the campus book store and they will not buy it back, because this course is only taught in alternate years. Prerequisites: Introductory geology and/or oceanography; CHEM 1111 General Chemistry or equivalent; comfort with algebra and calculus (differentials). Grading: 40% homework, 25% midterm exam, 25% final exam, 10% class participation including attendance. Undergraduate and graduate homework assignments and exams will be slightly different, and the two groups will be evaluated separately. Homework: Six problem sets will allow students to apply what they have learned in class to practical problems. Math will generally be limited to algebra and basic calculus. Homework assignments are to be handed in during class (generally one week after being assigned), and late assignments will lose 10% credit per day (not per class meeting). If late assignments are left in Marchitto's GEOL mailbox, they must be stamped Received by a member of the office staff during business hours. Problem Set 1 due 9/6 Exams: Midterm and final exams will include short answer and (for graduate students) longer answer questions, and will stress, but are not limited to, Critical Concepts. _________________________________________________________________________________ Religious or other obligations: If you have any conflicts with scheduled exams because of religious or other obligations, please notify me at least two weeks in advance of the conflict to request special accommodation. See Registrar's policy on final exam conficts (three on same day). Disabilities: If you qualify for accommodations because of a disability, please submit to me a letter from Disability Services within the first two weeks of class, so that your needs may be addressed. Disability Services determines accommodations based on documented disabilities. Note on academic honesty: Students are allowed to work together on homework problems, but are not allowed to simply copy each other’s work. Copying constitutes cheating under the CU Honor Code. _________________________________________________________________________________ T 8/23: Introduction to marine chemistry and geochemistry Th 8/25: Composition of seawater: Major elements T 8/30: Internal cycling of elements Th 9/1: Ions and their behavior T 9/6: Tracer conservation and ocean transport Th 9/8: Upper ocean circulation T 9/13: Deep ocean circulation Th 9/15: Air-sea exchange T 9/20: Biological primary production Th 9/22: Limiting nutrients T 9/27: Organic matter in the water column Th 9/29: Nitrogen and phosphorous cycles T 10/4: Carbonate system in seawater Th 10/6: Ocean pCO2 T 10/11: CaCO3 cycling Th 10/13: Anthropogenic CO2 invasion T 10/18: Midterm Exam
Th 10/20: Stable isotopes of C and N T 10/25: Silicate cycle Th 10/27: U-series radionuclides T 11/1: Marine sediments Th 11/3: Pore water chemistry and diffusion T 11/8: Bacterial oxidation of organic matter in sediments Th 11/10: Fe, S, and Mn redox cycles T 11/15: Hydrothermal systems Th 11/17: History of ocean chemistry and the rise of cyanobacteria T 11/22, Th 11/24: Fall Break - No Class
T 11/29: Cenozoic weathering and atmospheric CO2 Th 12/1: Final Exam (in class) T 12/6, Th 12/8: Fall AGU - No Class
“The chemistry of the oceans is the chemistry of life writ large” -David Archer, U. Chicago
Professor: Tom Marchitto, tom.marchitto@colorado.edu
Office Hours: Thursdays 1-2 pm in Benson 435, or by appointment
Undergrad enrollment limited to juniors and seniors
3 Credits
Counts toward the Graduate Certificate in Oceanography
Problem Set 1 key
Problem Set 2 due 9/20
Problem Set 2 key
Problem Set 3 due 9/29
Problem Set 3 key
Problem Set 4 due 10/11
Problem Set 4 key
Problem Set 5 due 11/8
Problem Set 5 key
Problem Set 6 due 11/17
Problem Set 6 key
Class Schedule and Reading
Reading assignments include all subsections within a listed section, unless otherwise noted
Click on lecture title for PowerPoint file (password protected)
introduction, collecting seawater, collecting sediments
No reading
GEOSECS
JGOFS
WOCE
GEOTRACES
principle of constant proportions, salinity, 1-box model, steady state, residence time
Read S&G 1.1
non-conservative behavior, biological cycling, 2- and 3-box models
Read S&G 1.2-1.3
Nozaki's compilation of dissolved elements in the Pacific
MBARI periodic table of elements in the ocean
periodic tables, d0/d10/transition cations, speciation
Read Railsback (2003) accompanied by this table
Earth Scientist's Periodic Table
advection-diffusion, winds, Ekman transport, gyres
Read S&G 2.1-2.2
1st Homework due
density stratification, ventilated thermocline, tritium, 3He, CFCs
Read S&G 2.3
radiocarbon, water masses, meridional overturning circulation
Read S&G 2.4
Henry's law, stagnant film model, wind speed dependence, 14C and 222Rn methods
Read S&G 3.1-3.3
photosynthesis, measurement, nutrient supply, light, biological pump efficiency
Read S&G 4.1
2nd Homework due
Redfield ratio, trace metal biogeochemistry, Fe fertilization, phytoplankton
Read S&G 4.2 up through "Phytoplankton distribution and productivity," & read "The role of iron" on pp. 160-162
POM & DOM, remineralization, oxygen, sinking
Read S&G 5.1-5.2 & 5.4
phosphate, nitrification, denitrification, N fixation
Read S&G 5.3
3rd Homework due
electroneutrality, pH, alkalinity, DIC
Read S&G 8.1-8.2
Good book for more details: CO2 in Seawater: Equilibrium, Kinetics, Isotopes by Zeebe and Wolf-Gladrow
Carbonate system calculator online (CDIAC)
Carbonate system calculator in Excel (Ed Boyle)
Carbonate system calculator in Matlab script (Boyle/Marchitto)
DIC & Alk distribution, pCO2 systematics, pCO2 seasonality
Read S&G 8.3
coccoliths/foraminifera/pteropods, CaCO3 solubility, lysocline/CCD
Read S&G 9.1-9.4
4th Homework due
global carbon cycle, Revelle factor, ocean acidification
Read S&G 10.1-10.2
d13C, air-sea d13C, d15N, denitrification
Read C-13 and N-15 sections of Marchitto, 2007
diatoms, opal export, silicic acid distribution, Si*
Read S&G 7.1-7.3
decay chains, U-Th dating, 210Pb sed rates, particle tracers
Read sections 6.09.2, 6.09.5-6.09.5.2, 6.09.7-6.09.7.3 of Anderson, 2003
particle size, biogenic, terrigenous, authigenic
Read MG Chapter 1 by Futterer
pore water profiles, diffusion
Read MG Chapter 3-3.2.3 by Schulz
redox, half reactions, diagenetic sequence, bacteria
Read ToG 6.11.2 by Emerson & Hedges
5th Homework due
seawater redox potential, Fe oxides, pyrite, Mn nodules
No reading
water-rock interaction, phase separation, mineral deposits, chemosynthetic ecosystems
Read ToG 6.07.2-6.07.4 by German & von Damm
banded iron formations, rise of O2 & sulfate, seafloor spreading cycles, cyanobacterial modification of seawater
Read ToG 6.21.1-6.21.5.2 by Holland
6th Homework due
CO2 degassing vs. weathering, Sr isotopes, Os isotopes
Read ToG 6.20.3, 6.20.6 by Ravizza & Zachos