Lecture 13 - Deep Sea Sediments part 1 Flashcards
What are the dominant se sediments
1) red clays
2) siliceous ooze
3) calcerious ooze
4) terrigenous sediments
LOOK AT MAP IN LECTURE 13!!
for info on which is where in the oceans
Red clay properies
Mostly wind blow sediment, deposited at contiental margins.
Mostly quatz and clay minerals
What are the four main types of clay minerals
Kaolninte (formed in extreme chemical weathering)
Chlorite (igneous and metamohic rocks destroyed by chem weathering
Illite (aboudant and windspread)
Montmorillonite
Offshore antartic, what can be found here
Clay minerals produced by physical weathering (cold climate)
underneath clay produced by chemical weather (warm climate)
Volcanoes and ash
Volcanes emit ash and dust, the very smallest particals can travel around the world before they are deposited
The K-T boundary
this is a few cm thick, and tottaly deviod of fossils
What is the element that was used to disover a metore
Iridium
Properties of iridium
Very rare in the earths crust, present in cosmic dust and it was found an interval or time in each clay layer
What are the two types od Siliceous ooze
Diatoms and Radiolaria
Properties of Diatoms
Uniculluar alega with shels, abudance in high lat sillicous oozes
Radiolario properties
Zooplankton with silicoues tets, dominant compont of low lat
What are the controls od distribution on siliceous oozes
Supply, Preservation, Dilution
Main factor is siliecous ooze deposits
Upwelling forms nutrient rich waters which in turn producges high productivity and therefore high concetnrations of silicous oozes
How can diatoms be used with sea ice?
Diatoms can be used to map the changes in the sea ice (effecting the amount of co2 released from the atmopshere)