Abstract
A reconstruction of the palaeoenvironmental development of Altona
Bay, St. Croix, northeastern Caribbean, has been made based on the
sedimentological, geochemical and pollen analyses of a 1.83 m
long vibracore. For chronological control, AMS 14C measurements
were made at 5 levels downcore. The sedimentary sequence covers
the last c. 4,700 years, containing both (mangrove) peat and finegrained
clastic sediment units. Comparison with regional Holocene
sea level data demonstrates a gradual marine flooding of a mangrove
environment around 3,500 cal BP was presumably related to
a regional late Holocene sea-level rise, from a position, c. 2 m lower
than present. After a c. 1,000 year period of marine sedimentation
lasting until c. 2,500 cal BP, renewed formation of tropical wetland
occurred at the site. This development may be attributed to the increased
isolation of the shallow Altona Bay, most likely due to seaward
formation of a well-developed spit system and possibly under
the influence of enhanced storm-wave action in the period between
c. 4,000 and 2,200 cal BP. Since the 1960’s the repeated passage of
severe hurricanes (e.g. Hugo, 1989) has had a significant impact on
the sedimentation pattern of the bay and has caused a major hiatus
and the recent deposition of sediments immediately overlying the c.
2,500 year old peat.
Bay, St. Croix, northeastern Caribbean, has been made based on the
sedimentological, geochemical and pollen analyses of a 1.83 m
long vibracore. For chronological control, AMS 14C measurements
were made at 5 levels downcore. The sedimentary sequence covers
the last c. 4,700 years, containing both (mangrove) peat and finegrained
clastic sediment units. Comparison with regional Holocene
sea level data demonstrates a gradual marine flooding of a mangrove
environment around 3,500 cal BP was presumably related to
a regional late Holocene sea-level rise, from a position, c. 2 m lower
than present. After a c. 1,000 year period of marine sedimentation
lasting until c. 2,500 cal BP, renewed formation of tropical wetland
occurred at the site. This development may be attributed to the increased
isolation of the shallow Altona Bay, most likely due to seaward
formation of a well-developed spit system and possibly under
the influence of enhanced storm-wave action in the period between
c. 4,000 and 2,200 cal BP. Since the 1960’s the repeated passage of
severe hurricanes (e.g. Hugo, 1989) has had a significant impact on
the sedimentation pattern of the bay and has caused a major hiatus
and the recent deposition of sediments immediately overlying the c.
2,500 year old peat.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Geografisk Tidsskrift |
| Vol/bind | 108 |
| Udgave nummer | 2 |
| Sider (fra-til) | 59-70 |
| Antal sider | 12 |
| ISSN | 0016-7223 |
| DOI | |
| Status | Udgivet - 2008 |
| Udgivet eksternt | Ja |