Download - Clastic Sedimentology Introduction
Textbook: Introduction to Clastic Sedimentology
Downloadable from:http://spartan.ac.brocku.ca/~rcheel/teaching/sedimentology/SedNotes/
Topics to be covered:
1. Grain Texture (fundamental descriptors of granular material)
Grain size
Grain shape
Porosity and permeability
Grain orientation
2. Classification of terrigenous clastic rocks.
Arenite
Rudite
Lutite
3. Unidirectional fluid flow and sediment transport
Characteristics of unidirectional flows
Simple fluid flow
Fluid gravity flows
Sediment transport
Modes of transport
Initiation of transport
4. Bed forms and stratification under unidirectional flows
Bed forms
Terminology
The sequence of bed forms
Bed form stability fields
Cross-stratification formed by bed forms.
Terminology
Origin of cross-stratification
Cross-stratification and bed forms.
5. Flow, bed forms and stratification under oscillatory and combined flows
Characteristics of gravity waves
Bed forms and stratification under symmetrically oscillating currents
Bed forms and stratification under combined flows
The enigma of Hummocky Cross-stratification
Clastic Sedimentology:
The study of sediment and sedimentary rocks that are made up of particles that are the solid products of weathering at or near the Earth’s surface.
Gravel Sand Mud (silt and clay)
Conglomerate Sandstone Siltstone and Shale
Purpose of the course:
To introduce terminology and fundamental concepts for the description and interpretation of clastic sediment and sedimentary rocks.
Why study clastic sediment?
Sedimentary rocks make up only 7.9% of the Earth’s crust.
66% of the surface of the Earth is covered by sediment or sedimentary rocks.
Humans interact with the Earth largely at or near its surface.
At the same time they…..
Modify its physical and chemical properties so that it is no longer useable by them.
It is important to understand the various properties of the sedimentary cover and have systematic methods for describing these properties.
Hide garbage and other waste material in it.
Based on the recognition of the signature of changing environments over time, as preserved in the rock record.
Environmental interpretation of rocks
+
Age of rocks
= Earth History
Sedimentary rocks record the history of changing environments on Earth.
Large scale cross-bedding in 240million year old rocks in the Central US.
= windblown sand dunes; the Central US was a desert at thattime.
By examining the characteristics of various environments on Earth today we can interpret the environments in which ancient sediments were deposited.
The present is the key to the past.
Environmental interpretation: