Earth & Environmental Sciences
platinum group element
100%
chondrite
50%
impact structure
45%
crater
36%
impactite
35%
impactor
32%
siderophile element
26%
Eocene
24%
melt
20%
ejecta
19%
tektite
18%
asteroid
16%
rock
14%
deep drilling
13%
solar system
13%
Cretaceous-Paleogene boundary
13%
chronology
12%
astronomy
12%
Barents Sea
11%
extinction
11%
drilling
11%
meteorite
10%
fossil record
10%
lithology
10%
material
9%
cratering
9%
comet
9%
eukaryote
8%
geology
8%
project
7%
Cretaceous
7%
iron meteorite
7%
iron
6%
flood basalt
6%
mass spectrometry
6%
isotopic ratio
6%
mass extinction
6%
interplanetary dust
6%
plasma
5%
Paleogene
5%
geological time
5%
endosymbiont
5%
Physics & Astronomy
impact melts
48%
projectiles
41%
chondrites
35%
rocks
25%
platinum
24%
Ghana
19%
asteroid belts
15%
fossils
14%
chronology
12%
craters
12%
eukaryotes
11%
planets
9%
geology
7%
oceans
7%
chemistry
7%
signatures
7%
bombardment
6%
meteorites
6%
interrogation
6%
plates (tectonics)
6%
prokaryotes
5%
geochemistry
5%
biology
5%
astronomy
5%
continents
5%
solar system
5%
jacks
5%
general overviews
5%
magma
5%
lithology
5%