Quaternary uplift rates at a plate boundary, Lae urban area, Papua New Guinea
Abstract
Uplift along the southern margin of the South Bismarck plate in Papua New Guinea is a result of plate convergence, terrane docking and triple-junction migration. Lithofacies data combined with paleontological and 14C dating yield uplift rates for the Markham Valley north flank and the Lae urban area in the range 2.0-7.6 m/10 3 yr. These rates are established for the past 21,000 years and have probably obtained for 10 6 yr. Depositional surfaces > 8100 years old in the Lae urban area are tilted. The uplift may be occurring by steady creep or in episodic increments of > 1 m with recurrence intervals of the order of 10 2 yr, as seems to be the case for the northern Huon Peninsula terraces. If episodic uplift is occurring, earthquakes of magnitude > 7.0 can be anticipated accompanied by slump-induced tsunamis.
- Publication:
-
Tectonophysics
- Pub Date:
- June 1989
- DOI:
- 10.1016/0040-1951(89)90121-2
- Bibcode:
- 1989Tectp.163..105C