Unit 2: Introduction to
Sequence Stratigraphy
UNAVCO
Accommodation space
Tectonic subsidence + eustatic sea level = sedimentation rate + water depth strata.uga.edu
Cyclical deposition
strata.uga.edu
Parasequences
strata.uga.edu
Review: Walter’s Law
Limestone
Sandstone
Mudstone
Siltstone
Shallowing upwards
• “Facies adjacent to each other in a continuous vertical sequence also accumulated laterally”
• This only applies within parasequences, because it cannot apply to a section with unconformities
Parasequences
strata.uga.edu
Parasequence analysis
• Interpret your section: identify the parasequences and parts (lower, middle, upper) of one parasequence
• Find bed thicknesses for the whole parasequence and for each part (lower, middle, upper)
• Interpret your results: What is the sedimentation history?
All the images in this presentation have been provided by Steve Holland of University of Georgia. He has given
permission for them to be distributed with this learning module. If you wish to use them in any way outside of this learning module,
please seek separate permission.