Carnegie Ridge proposed ridge jumps

ID: 3-27

Ocean: Pacific
Spreading center type: Microplate spreading ridge
Time of cessation: Ca. 4 Ma, chron C2 (Anderson et al., 1976)
Subsequent active spreading center: Present-day Cocos-Nazca spreading center

Review of previous studies:

Meschede et al. (1998) suggest that there have been a number of small-scale ridge jumps at the Nazca-Cocos spreading centre in Panama Basin within the recent geological past. Meschede et al. (1998) propose that the ridge axis migrated by three successive jumps to the south-west over several million years, in concert with ridge-jumps of the Malpelo Ridge, which moved northward until the two centres became a central spreading centre.

Observations and comments:

At the scale of our investigation it is difficult to identify the exact location of the extinct spreading centre segments. The relief at the inferred axes locations are generally less than 300m, with gravity anomalies less than 10 mGal and profiles show irregular ocean floor rather than a marked trough or ridge.


Anderson, R.N., Moore, G.F., Schilt, S.S., Cardwell, R.C., Tréhu, A. and Vacquier, V., 1976. Heat flow near a fossil ridge on the north flank of the Galapagos Spreading Center. Journal of Geophysical Research, 81(11), pp.1828-1838.

Meschede, M., Barckhausen, U. and Worm, H.U., 1998. Extinct spreading on the Cocos Ridge. Terra Nova, 10(4), pp.211-216.

Maps showing the location of extinct ridge segments

Depth profiles across the axes of extinct ridge segments

Gravity profiles across the axes of extinct ridge segments