Earth & Environmental Sciences
platinum group element
100%
crater
50%
impactite
41%
chondrite
38%
impact structure
36%
impactor
32%
extinction
27%
asteroid
26%
Younger Dryas
24%
Eocene
24%
Cretaceous
23%
melt
23%
rock
22%
mass extinction
20%
deep drilling
19%
Cretaceous-Paleogene boundary
17%
siderophile element
17%
flood basalt
16%
isotope
16%
transition
15%
meteorite
15%
fossil record
14%
ejecta
14%
isotopic ratio
13%
cratering
13%
Bronze Age
12%
chronology
12%
plasma
12%
solar system
11%
Paleogene
11%
astronomy
11%
volcanism
11%
mass spectrometry
10%
geochemistry
10%
project
10%
geology
9%
iron meteorite
9%
eukaryote
9%
clay
9%
chemostratigraphy
9%
material
8%
drilling
8%
stable isotope
8%
provenance
8%
basin
7%
lithology
7%
lead isotope
7%
fossil
7%
iron
6%
isotopic analysis
5%
plate tectonics
5%
stalagmite
5%
endosymbiont
5%
Archean
5%
sediment
5%
shell
5%
Deep Sea Drilling Project
5%
Holocene
5%
organic matter
5%
isotopic composition
5%
emplacement
5%
iridium
5%
bivalve
5%
Physics & Astronomy
impact melts
43%
projectiles
34%
chondrites
29%
rocks
27%
platinum
21%
fossils
17%
craters
13%
Ghana
13%
chronology
12%
eukaryotes
12%
asteroid belts
10%
plates (tectonics)
9%
chemistry
8%
planets
8%
oceans
8%
spherules
7%
geology
7%
meteorites
6%
lithology
6%
prokaryotes
6%
signatures
6%
bombardment
5%
general overviews
5%
interrogation
5%
geochemistry
5%
biology
5%
astronomy
5%
continents
5%