Ribbon spacing in Venusian tessera: Implications for layer thickness and thermal state
Article first published online: 31 OCT 2002
Copyright 2002 by the American Geophysical Union.
Geophysical Research Letters
Volume 29, Issue 20, pages 61-1–61-4, October 2002
How to Cite
Ribbon spacing in Venusian tessera: Implications for layer thickness and thermal state, Geophys. Res. Lett., 29(20), 2000, doi:10.1029/2002GL015994, 2002., and ,
- Issue published online: 31 OCT 2002
- Article first published online: 31 OCT 2002
- Manuscript Accepted: 19 SEP 2002
- Manuscript Revised: 17 SEP 2002
- Manuscript Received: 29 JUL 2002
 We report on measurements of characteristic extensional wavelength represented by ribbons in Venusian tessera terrain. Fourier power spectra for ribbons in 35 areas from 9 geographic regions show dominant wavelengths of 2 to 6 km. We used these values to estimate mechanical layer thickness during ribbon formation at 0.6 to 2.9 km. Because ribbons accommodate extension of a single strong layer overlying a ductile substrate, we conclude that the base of this mechanical layer corresponded to the local brittle-ductile transition (BDT) during ribbon formation. Maintaining a BDT at <3 km depth for a significant length of time requires a locally hot environment, as over a plume impinging on thin lithosphere. These results indicate that locally hot conditions prevailed at widely distinct locations in the past.