Tectonic and climatic forcing on the Panj river system during the Quaternary

Abstract HKT-ISTP 2013 B

Anomalous luminescence of subglacial sediment at Haut glacier d'Arolla, Switzerland - a consequence of resetting at the glacier bed?

<p>Luminescence has the potential to elucidate glacial geomorphic processes because primary glacial sediment sources and transport pathways are associated with contrasting degrees of exposure to light. Most notably, sediment entrained from extraglacial sources should be at least partially reset, whereas sediment produced by glacial erosion of subglacial bedrock should retain substantial luminescence commensurate with a geological irradiation history.</p> <p>We set out to test the validity of this assumption at Haut Glacier d’Arolla, Switzerland using sediment sampled extraglacially and from the glacier bed. Contrary to our expectations, the subglacial samples exhibited natural signals that were substantially lower than those of other sample groups, and further (albeit limited) analyses have indicated no obvious differences in sample group luminescence characteristics or behaviour that could account for this observation. For glaciological reasons, we can eliminate both the possibility that the subglacial sediment has been extraglacially-reset or exposed in situ to heat or light. We therefore advocate investigation of possible resetting processes related to subglacial crushing and grinding, and speculate that such processes, if more generally present, may enable the dating of subglacially-deposited tills using luminescence-based techniques.</p&gt

Deformationsanalyse und mechanische Kopplung eines aktiven fore-arcs in Raum und Zeit, Kamtschatka, Russische Föderation

Seit dem Mesozoikum wächst die kontinentale Kruste am aktiven Plattenrand von Kamtschatka durch Akkretion allochthoner Terrane. Dieses Wachstum manifestiert sich in der differenziellen Exhumierung und Hebung tektonischer Blöcke innerhalb des Akkretionskeils, parallel zum Kamtschatka- Graben. Die Kinematik der Exhumierung soll mittels strukturgeologischer und neotektonischer Deformationsanalyse erfasst und mit thermochronologischen Untersuchungen an Apatiten bis etwa ins Untere Pliozän quantifiziert werden.conferenc

Geologie, Paläontologie und Geochronologie des Eem-Beckens Neumark-Nord 2 und Vergleich mit dem Becken Neumark-Nord 1 (Geiseltal, Sachsen-Anhalt)

Den Schwerpunkt dieser Arbeit bilden die Ergebnisse sedimentologischer, palynologischer, malakologischer und chronometrischer Untersuchungen an Sedimenten aus dem Zentralbereich des Paläoseebeckens Neumark-Nord 2. Die interdisziplinären Untersuchungen an dem 11 m mächtigen Hauptprofil A und benachbarten Profilen zeigen übereinstimmend, dass die limnische Sedimentation vom Ende des Saale-Komplexes über die Eem-Warmzeit bis in die Weichsel-Kaltzeit erfolgte. Das Profil lässt Seespiegelschwankungen mit einer generellen Tendenz der Verflachung und Verlandung sowie wechselnde Sedimentationsraten erkennen. Durch die palynologischen Untersuchungen sind außerdem mit Erosion und Sedimentumlagerungen verbundene Hiaten festgestellt worden. Eine von Laurat et al. (2006) und Mania et al. (2008, 2010) im Profil ausgewiesene zusätzliche Warmzeit, die durch eine Kaltphase von der Eem-Warmzeit separiert und zudem jünger als das Interglazial von NN1 sein soll, existiert nicht. Vor allem die palynostratigraphische, aber auch die malakologische Koinzidenz der Becken NN1 und NN2 belegt die Gleichaltrigkeit der Ablagerungen. Somit ist in Neumark-Nord zwischen der Saale-Grundmoräne der Zeitz-Phase und den periglaziären Bildungen der Weichsel-Kaltzeit nur eine Warmzeit nachweisbar, das Eem. Dies wird durch neue geochronologische Daten eindeutig verifiziert. Daher können die zuletzt von Mania et al. (2010) dokumentierten Lagerungsbeziehungen, nach denen die Beckenfolge von NN2 über der von NN1 liegen soll, nicht bestätigt werden. In Neumark-Nord werden die klimatischen Besonderheiten des Mitteldeutschen Trockengebietes während der Eem-Warmzeit deutlich. Insofern bietet der Vergleich der Eem-Vorkommen von Neumark-Nord, Gröbern und Grabschütz ein Lehrbeispiel für die standortspezifische Variabilität benachbarter synchroner Warmzeitprofile.researc

Muscle damage response in female collegiate athletes following repeated sprint activity

Exercise induced muscle damage (EIMD) is a well-investigated area, however there is a paucity of data surrounding the damage response in females. The aim of this study was to examine the damage responses from a sport-specific bout of repeated sprints in female athletes. Eleven well-trained females (mean ± SD; age 22 ± 3 y, height 166.6 ± 5.7 cm, mass 62.7 ± 4.5 kg) in the luteal phase of the menstrual cycle completed a repeated sprint protocol designed to induce EIMD (15 × 30 m sprints). Creatine kinase (CK), countermovement jump height (CMJ), knee extensor maximum voluntary contraction force (MVIC), muscle soreness (DOMS), 30 m sprint time and limb girth were recorded pre, post, 24 h, 48 h and 72 h post exercise. CK was elevated at 24, 48 and 72 h (p < 0.05), peaking at 24 h (+418%) and returning towards baseline at 72 h. CMJ height was reduced immediately post, 24 and 48 h (p < 0.05). Sprint performance was also negatively affected immediately post, 24 h, 48 h and 72 h post exercise. Muscle soreness peaked at 48 h (p<0.01) and remained significantly elevated at 72 h post exercise (p<0.01). Limb girth and MVIC did not alter over time. The current study provides new information on the EIMD response in trained females following a sport specific bout of repeated sprints. Importantly, this damage response has the potential to negatively affect performance for several days post-exercise

Rates of river incision across the main tectonic units of the Pamir identified using optically stimulated luminescence dating of fluvial terraces

Calculated incision rates along the Panj, the main river of the Pamir, are used to investigate any influence by tectonics or climate on the architecture of the river. The depositional ages of Panj River terraces were calculated using optically stimulated luminescence (OSL) dating of terrace sand. Fluvial incision rates were generated by integrating the terrace depositional ages with accurate kinematic GPS measurements of terrace heights above the modern Panj. We investigated 16 terraces along the Panj at the western Pamir margin and one terrace from the Vakhsh River to the north of the Pamir. The results reveal brief periods of fluvial deposition over the past 26 kyr. The oldest Panj terrace depositional ages coincide with early MIS 2 and MIS 2/1 glaciations on the Pamir Plateau. Younger terrace ages have no apparent link with glacial cycles. Terraces with varying heights above the modern Panj at different localities yielded similar depositional ages. This suggests that local conditions have determined fluvial incision rates. Combining all of the terrace measurements, the average incision rate of the Panj over the last 26 kyr has been ~ 5.6 mm/yr. A high mean incision rate of ~ 7.3 mm/yr was calculated from terraces where the Panj has cut a steep-sided valley through the Shakhdara dome. Significantly lower incision rates (~ 2–3 mm/yr) were calculated from terraces where the Panj flows along the southern boundaries of the Shakhdara and Yazgulom domes. At those localities, graded segments of the Panj River profile and increased valley widths are indicative of local base levels. Downstream of the Yazgulom dome, river incision rates are generally lower (~ 4–5 mm/yr) than the Panj average. However, there is one exception where higher incision rates (~ 6 mm/yr) were calculated upstream of the Darvaz Fault Zone, a major tectonic feature that forms the western boundary of the Pamir. The Vakhsh River terrace to the north of the Pamir yielded a lower incision rate (~ 3 mm/yr) compared to the Panj average. Variation in incision rates along the Panj does not correspond to changes in rock type or river catchment area. Instead, incision rates appear to have been primarily influenced by river capture across the southern and central metamorphic domes of the Pamir. Wherever the Panj cuts these domes it displays a convex river profile. The combination of localized river profile convexity and changes in incision rates across the Pamir domes indicates that the dome boundaries have been active recently

The raised bogs of Mecklenburg-Vorpommern - First analysis of the investigations for the raised bog conservation programme in Mecklenburg-Vorpommern, FRG

Der gegenwärtige Arbeitsstand am Regenmoor-Schutzprogramm des Bundeslandes Mecklenburg-Vorpommern wird vorgestellt. Im Rahmen der für das Schutzprogramm notwendigen Untersuchungen wurden die Moore vegetationskundlich und hydrologisch kartiert. Zahlreiche lithostratigraphische und geochronologische Untersuchungen trugen dazu bei, die ökologische und geologische Entwicklung der Moore zu klären. Die Ergebnisse zeigen, daß eine erfolgreiche Renaturierung nur dann erfolgen kann, wenn die Moore zusammenhängend, in ihrem gesamten ehemaligen Ausmaß, d.h. auch mit den umgebenden Niedermoorbereichen vernäßt werden. Die Ergebnisse von 3 Jahren werden zusammengefaßt dargestellt.The state of a research project on preparing a raised bog conservation programme in the Mecklenburg-Vorpommem region (NE-Germany) is presented. Mapping of the vegetation and hydrological conditions of the bogs has been carried out. By the help of lithostratigraphic and geochronologic research the ecological and geological evolution of the raised bogs could be reconstructed in that region. The results show, that a successful renaturalization is only possible by rewetting the bogs over the entire former area, which includes the fen area too. The results of 3 years of research study are presented in summarized form.researchDFG, SUB Göttingen, DGM