LIPs

Question 1

What are the six different types of LIPs?

Answer 1

1. CFBs
2. Volcanic Rifted Margins - VRM
3. Oceanic Plateaus (largest) - OPs
4. Ocean basin flood basalts - OBFBs
5. Submarine Ridges - SRs
6. Seamounts

Question 2

What is a continental flood basalt?

Answer 2

Basalt that is continental breakup related.
Characterised by stacked successions of lava flows up to kilometre thick, but in anastamosing stacks, so none will contain complete sed succession.

Question 3

What is a volcanic rifted margin?

Answer 3

Produced when continental crust breakups up pre- or syn- volcanic magmatism

Question 4

What is an oceanic plateau?

Answer 4

The largest type of LIP, these are broad plateaus of mafic or intermediate rock that intrude into sea floor and can sit up to 2km above the seafloor. Because of their composition, they are actually buoyant and will not be subducted.

Question 5

What is an Ocean Basin Flood Basalt?

Answer 5

An extensive submarine lava flow/sill lying above and younger than normal oceanic crust basement. Form at abyssal depths.

Question 6

What is a seamount?

Answer 6

Similar to hotspot volcanism, an areally extensive LIP but lower average production rate of magma.

Question 7

What is the longest extent of LIP volcanism?

Answer 7

Around 50Ma

Question 8

When is most of the magma emplaced?

Answer 8

Within pulses of around 1-5Ma long

Question 9

How much magma can be emplaced in a LIP?

Answer 9

Up to 1,000,000’s of km^3

Question 10

What is a critical characteristic of a LIP?

Answer 10

Rapid mantle melt production rate, much higher than at the plate boundaries. Rapid emplacement rate.
Pulsed magmatism (3/4 of volume can be released in 1-5 Ma)