Scientific drilling of the Boltysh impact crater, Ukraine

Introduction: The Boltysh crater has been known for several decades and was first drilled in the 1960s as part of a study of economic oil shale deposits. Unfortunately, the cores were not curated and have been lost. We have re-drilled the impact crater and have recovered a near continuous record of ~400 m of organicrich sediments together with 15 m of suevite

Organic geochemistry of the Boltysh impact crater, Ukraine

The Boltysh crater has been know for several decades and was originally drilled in the 1960s - 1980s in a study of economic oil shale deposits. Unfortunately, the cores were not curated and have been lost. However we have recently re-drilled the impact crater and have recovered a near continuous record of ~400m of organic rich sediments deposited in a deep isolated lake which overly the basement rocks spanning a period ~10 Ma. The Boltysh impact crater, centred at 48°54–N and 32°15–E is a complex impact structure formed on the basement rocks of the Ukrainian shield. The age of the impact is 65.17±0.64 Ma [1]. At 24km diameter, the impact is unlikely to have contributed substantially to the worldwide devastation at the end of the Cretaceous. However, the precise age of the Boltysh impact relative to the Chicxulub impact and its location on a stable low lying coastal plain which allowed formation of the postimpact crater lake make it a particularly important locality. After the impact, the crater quickly filled with water, and the crater lake received sediment input from the surrounding land surface for a period >10 Ma [2]. These strata contain a valuable record of Paleogene environmental change in central Europe, and one of very few terrestrial records of the KT event. This preeminent record of the Paleogene of central Europe can help us to answer several related scientific questions. What is the relative age of Boltysh compared with Chicxulub? How long was the hydrothermal system active for after the impact event? How did the devastated area surrounding the crater recover, and how rapid was the recovery? The first sediments to be deposited in the crater lake were a series of relatively thin turbidites, the sediments then become organic rich shales and oil shales. Within the core there is ~400 m of organic rich shales/oil shales spanning a period of ~10 Ma some of which contain macrofossils such as ostracods, fish and plant fossils. Preliminary palynological studies suggest initial sedimentation was slow after the impact followed by more rapid sedimentation through the Late Paleocene. Hydrocarbons extracted from these samples are commonly dominated by terrestrial n-alkanes (Fig 1), Hopanes (including 3-methylhopanes) and steranes are also abundant and indicate the immaturity of the samples. The immaturity of samples is also evident from the abundance of hopenes, sterenes and oleanenes especially in the upper section of the core. In some of the oil shales the hopenes and sterenes are the most abundant hydrocarbons present. There is variation in the distribution of hydrocarbons/biomarkers and palynology throughout the core caused by changing inputs and environmental conditions

Organic geochemistry of the crater-fill sediments from Boltysh impact crater, Ukraine

The Boltysh impact crater, is a complex structure formed on the basement rocks of the Ukrainian shield which has been dated at 65.17±0.64 Ma [1]. The Boltysh crater has been know for several decades and was originally drilled in the 1960s-1980s in a study of economic oil shale deposits. Unfortunately, the cores were not curated and have been lost. However we have recently re-drilled the impact crater and have recovered a near continuous record of ~400 m of organic rich sediments deposited in a deep isolated lake which overlie the basement rocks spanning a period ~10 Ma. At 24km diameter, Boltysh will not have contributed substantially to the worldwide devastation at the end of the Cretaceous. However, the precise age of the Boltysh impact relative to the Chicxulub impact and its location on a stable low lying coastal plain which allowed formation of the postimpact crater lake make it a particularly important locality. After the impact, the crater quickly filled with water in a short marine phase but returned to fresh water which persisted for >10Ma [2]. These strata contain a valuable record of Paleogene environmental change in central Europe, and one of very few terrestrial records of the KT event. This pre-eminent record of the Paleogene can help us to answer several related scientific questions including the relative age of Boltysh compared with Chicxulub, recovery from the impact, and later climate signals. The organic geochemistry and playnology indicate main inputs to be algal and higher plant within most of the core although there are some marked changes in inputs in some sections. A number of carbon isotope excursions are also present within the core which are currently being further investigated

MOXE: An X-ray all-sky monitor for Soviet Spectrum-X-Gamma Mission

A Monitoring Monitoring X-Ray Equipment (MOXE) is being developed for the Soviet Spectrum-X-Gamma Mission. MOXE is an X-ray all-sky monitor based on array of pinhole cameras, to be provided via a collaboration between Goddard Space Flight Center and Los Alamos National Laboratory. The objectives are to alert other observers on Spectrum-X-Gamma and other platforms of interesting transient activity, and to synoptically monitor the X-ray sky and study long-term changes in X-ray binaries. MOXE will be sensitive to sources as faint as 2 milliCrab (5 sigma) in 1 day, and cover the 2 to 20 KeV band

Boulder trains in western Massachusetts

Guidebook for field trips in western Massachusetts, northern Connecticut and adjacent areas of New York: 67th annual meeting October 10, 11, and 12, 1975: Trip C-

Permanent Draft Genome Sequence of Frankia sp. Strain ACN1ag, a Nitrogen-Fixing Actinobacterium Isolated from the Root Nodules of Alnus glutinosa

Frankia strain ACN1ag is a member of Frankia lineage Ia, which are able to re-infect plants of the Betulaceae and Myricaceae families. Here, we report a 7.5-Mbp draft genome sequence with a G+C content of 72.35% and 5,687 candidate protein-encoding genes

Satellite power system: Concept development and evaluation program. Volume 3: Power transmission and reception. Technical summary and assessment

Efforts in the DOE/NASA concept development and evaluation program are discussed for the solar power satellite power transmission and reception system. A technical summary is provided together with a summary of system assessment activities. System options and system definition drivers are described. Major system assessment activities were in support of the reference system definition, solid state system studies, critical technology supporting investigations, and various system and subsystem tradeoffs. These activities are described together with reference system updates and alternative concepts for each of the subsystem areas. Conclusions reached as a result of the numerous analytical and experimental evaluations are presented. Remaining issues for a possible follow-on program are identified

Permanent Draft Genome Sequence of Frankia sp. Strain AvcI1, a Nitrogen-Fixing Actinobacterium Isolated from the Root Nodules of Alnus viridis subsp. crispa Grown in Canada

Frankia strain AvcI1, isolated from root nodules of Alnus viridis subsp. crispa, is a member of Frankia lineage Ia, which is able to reinfect plants of the Betulaceae and Myricaceae families. Here, we report a 7.7-Mbp draft genome sequence with a G+C content of 72.41% and 6,470 candidate protein-encoding genes

Density of bulk trap states in organic semiconductor crystals: discrete levels induced by oxygen in rubrene

The density of trap states in the bandgap of semiconducting organic single crystals has been measured quantitatively and with high energy resolution by means of the experimental method of temperature-dependent space-charge-limited-current spectroscopy (TD-SCLC). This spectroscopy has been applied to study bulk rubrene single crystals, which are shown by this technique to be of high chemical and structural quality. A density of deep trap states as low as ~ 10^{15} cm^{-3} is measured in the purest crystals, and the exponentially varying shallow trap density near the band edge could be identified (1 decade in the density of states per ~25 meV). Furthermore, we have induced and spectroscopically identified an oxygen related sharp hole bulk trap state at 0.27 eV above the valence band.Comment: published in Phys. Rev. B, high quality figures: http://www.cpfs.mpg.de/~krellner