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| Titel |
Climate variability during MIS 7, MIS 5 and the Holocene recorded in a stalagmite from western Germany |
| VerfasserIn |
D. Scholz, D. Hoffmann, Christoph Spötl, A. Mangini, D. K. Richter, S. Niggemann |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250028258
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| Zusammenfassung |
| We present high-resolution stable isotope (i.e., δ18O and δ13C) and trace element
profiles for stalagmite HBSH-1 from Hüttenbläserschachthöhle, western Germany.
The cave was discovered in 1993 and is one of the biggest caves of the giant cave
system of Iserlohn with a length of 4360Â m. Other caves of this system are the
nearby Dechen-, Bunker- and B7-Höhle, and stalagmites from these caves already
provided important insights into past climate variability in Germany (Niggemann et
al., 2003a; Niggemann et al., 2003b; Kluge et al., 2008). Stalagmite HBSH-1 was
collected deep inside the cave, is about 55Â cm long and shows a clearly visible
lamination.
The U-content of the stalagmite is rather high (i.e., between 4 and 12 μg/g), which allows
both determination of very precise 230Th/U-ages and analysis of very small sample
sizes (i.e., between 1 and 2Â mg of calcite) with the MC ICPMS technique. Thus, it
is possible to determine the beginning and end of individual growth phases very
precisely.
Our stalagmite record covers the important climate phases of Marine Isotope Stage (MIS)
7 and 5 as well as the Holocene. 230Th/U-dating shows so far that HBSH-1 started growing at
~215Â ka, which is in agreement with the beginning of (MIS) 7.3 in the Austrian Alps (Spötl
et al., 2008). During the remainder of MISÂ 7 the stalagmite shows intermittent growth until
~189Â ka, in agreement with the timing of the end of MISÂ 7.1 (Spötl et al., 2008). Stalagmite
growth reinitiated after a long-lasting hiatus at ~131Â ka, which marks the beginning of
MISÂ 5.5. The corresponding growth phase has a length of approx. 25Â cm and, thus,
represents the largest part of the sample. It also exhibits the highest growth rate
of ~12 μm/a and, thus, has a very high resolution. At ~113 ka the stalagmite
shows a short hiatus of approx. 4Â ka. Growth reinitiated at ~109Â ka and continued
uninterruptedly (i.e., also during the cold interstadial MISÂ 5.2) until ~78Â ka, albeit with
a slower growth rate of 5.6 μm/a. The top 5 cm of the stalagmite grew during
the Holocene. The timing of this growth phase has not been precisely determined
yet.
The high U-content of our sample and the fact that it also grew during relatively cold
phases will allow a precise determination of the timing and duration of the climate
phases recorded in HBSH-1. We compare our stalagmite record with local and
European proxy records as well as with precisely dated climate records on a global
scale.
References
Kluge, T., Marx, T., Scholz, D., Niggemann, S., Mangini, A., and Aeschbach-Hertig,
W., 2008. A new tool for palaeoclimate reconstruction: Noble gas temperatures
from fluid inclusions in speleothems. Earth and Planetary Science Letters 269,
407-414.
Niggemann, S., Mangini, A., Richter, D. K., and Wurth, G., 2003a. A paleoclimate record
of the last 17,600 years in stalagmites from the B7-cave, Sauerland, Germany. Quaternary
Science Reviews 22, 555-567.
Niggemann, S., Mangini, A., Mudelsee, M., Richter, D. K., and Wurth, G., 2003b.
Sub-Milankovitch climatic cycles in Holocene stalagmites from Sauerland, Germany. Earth
and Planetary Science Letters 216, 539-547.
Spötl, C., Scholz, D., and Mangini, A., 2008. A terrestrial U/Th-dated stable isotope
record of the Penultimate Interglacial. Earth and Planetary Science Letters 276, 283-292. |
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