Info

Fern-spore spike

No

No

Yes

Yes

Yes

Iridium anomaly

1.27 ppb

1.6 ppb (44)

71 ppb

No

0.49 ppb

Claystone layer

No

No

No

No

No

Shocked minerals

No

No

No

No

No

Magnetostratigraphy

No

No

No

No

No

Radiometric dates

Yes

No

No

No

No

K vertebrates below

Yes

No

No

No

Yes (45)

T vertebrates above

No

No

No

No

No

K leaves below

No

No

Yes

Yes

Yes

T leaves above

No

No

Yes

Yes

Yes

(7) Lerbekmo and Coulter (1984)

(12) Johnson and Hickey (1990)

(14) Baadsgaard and Lerbekmo (1980)

(15) Archibald et al (1982)

(16) Shoemaker et al (1987)

(18) Nichols and Fleming (1990)

(24) Raynolds and Johnson (2003)

(27) Leffingwell (1970)

(29) Sweet and Braman (2001)

(35) Mclver and Basinger (1993)

(36) Sweet and Braman (1992)

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