391 documents found in 250ms
# 381
Kamm, H • Machon, L • Donner, S
Abstract: The main objective of this drilling fluid analysis was the detection of inflows of formation fluids. Therefore different gases dissolved in the drilling mud were measured continuously and automatically at drill site with three different methods (Fig.: KTB-Report 92-2 page C13). The operation principles of the mass spectrometer and the gaschromatograph have been explained by STROH et al. (1988) and FIGGEMEIER et al. (1991). The principle of radon determination is published by ERZINGER et al. (1992). In the complete KTB-VB and in in the KTB-HB down to a depth of 3003 m the gas phase was released and collected by twirl degassers attached in front of the mud shakers. This open system led to gas losses as well as air contamination. Therefore results obtained down to this depth have only qualitative character. After casing the KTB-HB to a depth of 3003 m a bypass system was installed at the BOP (blow-out preventer) 50 cm below the flow line.
# 382
Fietz, Susanne • Sturm, Michael • Nicklisch, Andreas
Abstract: Calculations were based on factors established for 89 water samples across Lake Baikal in July 2001 (see text). The traps were deployed for about 16 months and the core top spanned c. 7 years (see text).According to the contribution to the chlorophyll a-model shown in Eq. (1), the chlorophyll a content in the water of the south basin in July 2001 was composed of 30% Bacillariophyceae plus Chrysophyceae, 44% Chlorophyta, and 26% cyanobacterial picoplankton. In the 40-m trap, in contrast, 87% of the chlorophyll a originated from Bacillariophyceae plus Chrysophyceae, 11% from Chlorophyta, and 2% from cyanobacterial picoplankton (Fig. 5). The percentage contribution did not change with the water depth, as the same composition was found in the deepest traps (Fig. 5).
# 383
Fietz, Susanne • Sturm, Michael • Nicklisch, Andreas
Abstract: Fig. 4 visualises differences in the degradation between the organic compounds, chlorophylls, and carbon. The chlorophyll a/carbon ratio decreased with depth, indicating that organic carbon is more slowly degraded than chlorophyll a (Table 6 and Fig. 4), whereas the pheophytin a/carbon ratio and the pyropheophytin a/carbon ratio increased with the depth, indicating the formation of pheophytin and pyropheophytin with depth (Table 6 and Fig. 4). Best fits for the chlorophyllide a/carbon ratio and pheophorbide a/carbon ratio vs. depth were also linear regression models, but they were not significant (Fig. 4).
# 384
Fietz, Susanne • Sturm, Michael • Nicklisch, Andreas
Abstract: The traps were deployed for about 16 months. The respective regression equations and its coefficients of determination (r2) are reported in Table 5.In the 40-m trap, fucoxanthin was the dominant carotenoid (Table 1 and Fig. 3). Other pigments of Bacillariophyceae plus Chrysophyceae (chlorophyll c, diadinoxanthin, and diatoxanthin) as well as the cyanobacterial zeaxanthin also showed high sedimentation rates, whereas the chlorophyte chlorophyll b and lutein, as well as the cryptophyte alloxanthin, sedimented only in low amounts (Table 1 and Fig. 3). Abbreviations: Chl—chlorophyll, Fuco—fucoxanthin, Zea—zeaxanthin, β-car—β-carotene, Allo—alloxan
# 385
Fietz, Susanne • Sturm, Michael • Nicklisch, Andreas
Abstract: During 16 months of deployment, 239 g m−2 dry matter settled in the 40-m trap, with an average flux of 14.9 g m−2 month−1 (Table 2 and Fig. 2). The content of organic carbon was 21.9% at that depth and that of total nitrogen 1.6% (Table 2 and Fig. 2). The resulting atomic C/N ratio of 15 indicated that the sedimented material resulted from the autochthonous production by suspended phytoplankton and that terrigenous input is likely to be negligible at that site. The amount of pigments gathered during the 16 months deployment in the 40-m trap was 193.1 μmol m−2 for chlorophyll a and 797 μmol m−2 for chlorophyllide a+pheopigment a. The average flux was hence 61.8 μmol m−2 month−1 settled chlorophyll a+chlorophyllide a+pheopigment a (Table 1). It is worth noting that the replicate samples of the 40-m trap deviated strongly (coefficient of variation: 60.5%), whereas the coefficients of variation for the replicate samples in the traps
# 386
Fagel, Natalie • Alleman, Laurent • Granina, L • Hatert, F • Thamo-Boszo, Edit • (et. al.)
Abstract: The unit-cell parameters (Table 4) were calculated with the least-squares refinement program LCLSQ 8.4 (Burnham, 1991), from the d-spacings corrected with an internal standard of Pb(NO3)2.
# 387
Demory, Francois • Oberhänsli, Hedi • Nowaczyk, Norbert • Gottschalk, Matthias • Wirth, Richard • (et. al.)
Abstract: Higher abundance of greigite during glacial intervals coincides with small increases of the S content (Fig. 11B). Greigite levels in glacial sediments cannot be correlated between cores (Fig. 12), which suggests that greigite concentrations are driven by local processes. We suggest that faecal pellets could be a suitable microenvironment for sulphate reduction. And while greigite could potentially act as proxy for faecal pellets in glacial sediments, unfortunately, we cannot rely on this possible indicator since the greigite is very sensitive to onshore alterations after sampling (Snowball and Thompson, 1990).
# 388
Demory, Francois • Oberhänsli, Hedi • Nowaczyk, Norbert • Gottschalk, Matthias • Wirth, Richard • (et. al.)
Abstract: Increased presence of greigite (high SIRM/κLF) coincides with maximum sulphur contents observed at the beginning of interglacial stages (Fig. 11A). At similar levels in another sediment core of Lake Baikal, Watanabe et al. (2004) observed pyrite mineralization. They attributed these pyrite-rich levels to mineralization at sediment/water interface under anoxic bottom water conditions. However, we prefer to interpret the greigite as a result of magnetite transformation when sulphate reduction occurs in the interglacial sediments. Peak sulphur contents would therefore be due to sulphur mineralization within the sediment and would not result from an enrichment of the sediment in sulphur at the sediment/water interface.
# 389
Demory, Francois • Oberhänsli, Hedi • Nowaczyk, Norbert • Gottschalk, Matthias • Wirth, Richard • (et. al.)
Abstract: In selected intervals, we measured titanium and iron contents in parallel to rock magnetic parameters (Fig. 9). Titanium content is a good reflection of detrital input since minerals containing titanium are not very sensitive to dissolution. Iron, however, is rather mobile and involved in the redox history of highly porous sediments: the spike of iron observed on top of the sedimentary column (Fig. 9A) marks the redox front. We observed a strong similarity between the titanium and HIRM curves: the detrital input decreases from the late glacial to the Holocene. In ancient sediments, HIRM and titanium display similar variations with high values in glacials and low values in interglacials (Fig. 9B).
# 390
Grünthal, Gottfried • Wahlström, Rutger
Abstract: The EMEC earthquake catalogue is an extension in time and space of the CENEC catalogue (Grünthal et al., 2009, http://doi.org/10.1007/s10950-008-9144-9). It consists of some 45,000 entries in Europe and the Mediterranean area and extends to the west to encompass the North Atlantic Ridge. The criteria are Mw ≥ 3.5 for events with latitude ≥ 44°N and Mw ≥ 4.0 for events with latitude < 44°N, in the time period 1000-2006. Data within the catalogue area can be obtained as ASCII-file through the EMEC Earthquake Catalogue Web Service. This webservice also enables the creation of seismicity maps according to user's specifications. In addition, a list of earthquakes in the time period 300-999 for Mw ≥ 6.0 in the catalogue area with latitude ≤ 40°N and longitude ≥ 10°E is given and a list of fake events in the time period 1000-1799.
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