ANDEEP I - Target 1
ANDEEP II - Targets 6, 4, 3, 2, with 7 as an alternative to 6
Particle Size Analysis
Adresslist
Taxonlist
Cruise Report.pdf

The ANDEEP project will:

• conduct the first base-line survey of the deep-water benthic faunas of the Scotia and Weddell seas, and
• document the variety of sea-floor habitats present within their submarine geographical settings.

The scientific objectives of ANDEEP are:

• to investigate the evolutionary processes and oceanographic changes which have resulted in the present biodiversity and distributional patterns in the Antarctic deep seas
• to investigate the influence of sea-floor habitat diversity on species and genetic diversity in the Antarctic deep sea
• to investigate the colonisation and exchange processes of the deep sea fauna in relation to changes in sea-bed geography over geological time
• to assess the importance of the Antarctic region as a possible source for many of the deep sea benthic taxa in other oceans.

The deeper waters of the Scotia and Weddell seas are some of the least explored parts of the world¹s oceans and we know almost nothing about the bottom-dwelling (benthic) animals that inhabit them. By contrast, we know that the present-day benthic animals of the Antarctic continental shelf exhibit many striking and unusual features, including gigantism, longevity, an extraordinarily high degree of endemism, and absence of taxa which are abundant in similar environments elsewhere. Such attributes are believed to reflect the geographical and hydrographical isolation of the shelves and their special environmental characteristics, particularly the persistently cold climate combined with high and markedly seasonal primary production. Periodic extensions of the ice sheet may have enhanced speciation processes on the continental shelf - the Antarctic "diversity pump".

Waters deeper than 1000 m, however, have broad connections with the Pacific, South Atlantic and Indian oceans and might therefore be expected to be much less isolated. If so, might the faunas of the bathyal and abyssal areas around Antarctica be similar to those of comparable depths elsewhere?

It is possible that the deep bottom water production in the Weddell Sea acts as a distribution mechanism, driving Antarctic deep-water faunas northwards into the Atlantic Ocean over evolutionary time-scales. Thus the Weddell Sea may be an important source for taxa presently living in the Atlantic and other neighbouring parts of the deep oceans.

Furthermore, the more-or-less isothermal water column of the Weddell Sea and the surroundings of the Antarctic continent provides an obvious conduit for the migration of shallow-water species into the deeper waters.

The Scotia-Weddell sea region has a long and complicated plate tectonic history, which has provided a rich and changing variety of habitats and environmental conditions for marine life over geological time. Whereas the formation of the Weddell Sea began during Jurassic time (165 million years ago), a continental link between South America and Antarctica persisted until a little more than 20 million years ago. The disruption of this link and the dispersal of its continental fragments allowed the inception of the Circum-Polar Current and caused the geographical and climatic isolation of Antarctica. These geographical and climatic changes, including intermittent periods of global warming and global sea-level rise and fall, are likely to have influenced migration in and out of the Antarctic region.

The continental remnants of the old land link now form many of the islands within the Scotia arc, whereas others are submarine islands, 1000 m below sea level, and possible refuges for animals exiled from the Antarctic continental shelf by advancing ice sheets. A chain of volcanoes, the South Sandwich Islands, and their associated subduction trench (> 7000 m) to the west represent a highly active tectonic environment that contrasts with the weakly active trench off the South Shetland Islands.

To address these issues, seven areas of the deep sea, and of submerged continental blocks which might be faunal refuges, have been selected for investigation.

1. Name: Prof. Dr. Angelika Brandt

   Institute: Zoological Institute and Zoological Museum
   Address: Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
   Phone: +40-40-4123-2278
   Fax: +40-40-4123-3937
   Email: abrandt@zoologie.uni-hamburg.de

2. Title of Proposal

   Antarctic benthic deep-sea biodiversity (ANDEEP):
   colonization history and recent community patterns
   
   

3. Required Ship Time

   • calculation of required time on station or along transects (in hours), based on clearly understandable, detailed work plan

? For reasons of shiptime only a selected set of gears can be employed at the different transects proposed. These are summarized in the following table (time frame only covers pure wire time, without wire change or shiptime)

LEG 1 (Punta Arenas - Punta Arenas) (five weeks)

the Drake Passage transect of 2x 1000 m, 1500 m, and 3500-4000 m stations (compare 4) will require 58 h @ 2.4 days

the other two planned transects with stations at 750, 1000, 1500, 2500, and 3500-4000 m depth will require 2x 82.9 hours @ 7.0 days

time allowance for wire change, winch problems, etc. is @ 4.0 days

the steaming time needed is roughly 14 days, calculated as follows:

• 3 days of steaming time between stations
• 2days of steaming time from Punta Areas to first Drake Passage station (@ 300 miles)
• 1 day of steaming time to last Drake Passage station (@ 180 miles)
• 2 days of steaming time to South Orkney Islands (@ 350 miles)
• 2 days of steaming time to east of the Antarctic Peninsula (@ 300 miles)
• 4 days of steaming time from the Antarctic Peninsula to Punta Arenas

? flexibility in calculation left for leg 1 approximatelly 1 week (for a leg of five weeks)

? This shiptime could potentially be used for an additional transect on the north side of the Drake Passage at about 57°S 67°W, at similar depths, which would require another 4-5 days of shiptime (including steaming and wire time).

1. Name: Prof. Dr. Angelika Brandt

   Institute: Zoological Institute and Zoological Museum
   Address: Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
   Phone: +40-40-4123-2278
   Fax: +40-40-4123-3937
   Email: abrandt@zoologie.uni-hamburg.de

2. Title of Proposal

   Antarctic benthic deep-sea biodiversity (ANDEEP):
   colonization history and recent community patterns
   
   

3. Required Ship Time

   • calculation of required time on station or along transects (in hours), based on clearly understandable, detailed work plan

? For reasons of shiptime only a selected set of gears can be employed at the different transects proposed. These are summarized in the following table (time frame only covers pure wire time, without wire change or shiptime)

LEG 2 (Punta Arenas - Punta Arenas) (seven weeks)

? the deep Weddell Sea transect will consist of three stations at 4000 m depth = 85.3 h @ 3.6 days

? the other three planned transects will require 3 x 82.9 hours @ 10.4 days

? time allowance for wire change, winch problems, etc. is @ 4.0 days

? the steaming time needed is roughly 24 days, calculated as follows:

• 3 days of steaming time between stations
• 7 days of steaming time from Punta Arenas to the first deep central Weddell Sea station
• 4 days of steaming time across the Weddell Sea to Kapp Norvegia (KN)
• 3 days of steaming time from KN to the South Sandwich Islands
• 2 day of steaming time to South Georgia
• 5 days of steaming time back to Punta Arenas

? flexibility in calculation left approximately 1 week (for a seven weeks leg)

The alternative to this proposed Antarctic deep-sea expedition consisting of two legs would be a 12 week expedition of one leg only. The advantage of two shorter legs would be to allow a higher number of scientists to participate. Some scientists may otherwise not be able to join the expedition because of time constraints.

Particle Size Analysis of ANDEEP II Stations. Raw, wet sediment samples run by JAHowe using a Coulter LS230 laser at the Scottish Association for Marine Science, Dunstaffnage Marine Laboratory. When quoting this dataset please acknowledge J.A. Howe, L. W. Carpenter and B. Diaz "Deep-water sedimentary environments of the northwestern Weddell Sea and South Sandwich Trench, Antarctica" Deep-Sea Research (In Prep). Further information is available from JAHowe, jaho@dml.ac.uk

ANDEEP_Stations_PSA.pdf