Abstract
The sedimentary record in large marine embayments holds important information on Holocene environmental and sea-level changes. This paper investigates the evolution of a large subtropical marine embayment, Maputo Bay, in southern Mozambique. Using a combination of sediment cores, stable isotope data, seismic reflection profiling and 14C dating, we show complex back-barrier changes during the Holocene and link these to stepped rises in sea level. Our data reveal a sea-level “slowstand” followed by an abrupt rise that we correlate with the 8.2 ka global rise in sea level. Sedimentological, isotope and seismic evidence point to a subsequent slowstand interspersed by two punctuated rises in sea level that formed clear tidal ravinement surfaces. Sedimentary changes in the embayment are primarily forced by sea-level change, whereby tidal ravinement surfaces sandwich normal regressive packages formed via marginal progradation and shallowing of the system during “slow-” or still-stands. Large marine embayment systems hold great potential in unravelling relative sea-level change. Axiomatically, this reduces their utility as archives of climate-change.
| Original language | English |
|---|---|
| Pages (from-to) | 25-36 |
| Journal | estuarine, coastal and shelf science |
| Volume | 193 |
| Early online date | 19 May 2017 |
| DOIs | |
| Publication status | Published (in print/issue) - 5 Jul 2017 |
Keywords
- Holocene
- Environmental changes
- Stratigraphy
- Shoreline progradation
- Stepped sea-level rise
- 8.2 ka event
