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Paleoclimate Records
The key to understanding the origins and evolution of subglacial lake environments is likely in subglacial sedimentary sequences.
These lakes are thought to contain sedimentary records that document how they and life evolved through time, and possibly the only records of glacial and paleoclimatic Cenozoic history of the interior of Antarctica.
Too little is known about ice sheet history to fully assess its role and significance in global Cenozoic climate. The history of the Antarctic interior is unknown for times beyond ice cores and it is these interior environments that may contain the key to understanding critical thresholds of ice sheet initiation, growth, and decay rates, and volume change.
Proxies need to be identified that are indicators of subglacial sedimentation processes. Proper interpretation of the geological record requires an understanding of the mechanisms that disrupt or destroy stratigraphic chronologies. Methods need to be developed to estimate the maximum age of subglacial lakes. Chronological tools must be developed for dating subglacial lake records.
The key to understanding the origins of subglacial lake environments may well be at the bottom of sedimentary sequences. The information recorded in cores is the best way to constrain the nature of the pre-glacial to subglacial transition. If subglacial lakes persist during glacial/interglacial transitions, subglacial lacustrine and hiatus-free deposition may have occurred over several million or even tens of millions of years. If subglacial lakes are unstable they may cease to exist for a period of time and such cessation events should leave distinct sedimentary records. Recognizing subglacial lake cessation events is important because these events affect how life is expressed over time.
If substantial sedimentary records can be recovered and decoded, paleoclimate records will be an invaluable aid in reconstructing the development of the Antarctic ice sheet and the paleoenvironmental history of the Antarctic interior.
Paleo-Records....The Long Version
Scientific questions related to paleoclimate:
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Do subglacial lakes contain decipherable records of past climate?
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Do subglacial sedimentary records fill gaps in the history of Antarctica’s interior and the evolution of ice sheets?
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What biological, chemical, and geological proxies can be used to interpret the timing of paleoenvironmental and climatic change and their timing from sedimentary records in subglacial environments?
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What role has Antarctica’s interior played in the glacial and paleoclimatic history of its margins and globally through the Cenozoic?
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What does the history of subglacial lakes tell us about the response of microbiological systems to climate change?
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What are the tell-tale signs of life’s evolution in icy environments that would inform the search for life elsewhere in our solar system?
For more details go to ... PALEORECORDS IN SALE SEDIMENTARY SEQUENCES
Related topics:
Selected Publications: to be added