Stratigraphic organisation,spatial distribution,palaeoenvironmental reconstruction,and demise of Lower Cretaceous (Barremian-lower Aptian) carbonate platforms of the Western Pontides (Black Sea region,Turkey)

Barremian-Lower Aptian platform carbonates (“Urgonian limestones”) of the northern margin of the Istanbul zone extend from Zonguldak to the Kurucasile area along the Black Sea coast. New stratigraphic data on the “Inpiri” Formation of the Inpiri-Kurucasile area are based on the identification of calcareous algae, foraminifera, and rudists. They show that this lithostratigraphic unit is stratigraphically and lithologically equivalent to the Ökü?medere Formation from Zonguldak. Some of the biostratigraphic markers are reported for the first time in Anatolia. Foraminifera are represented by several forms with a significant biostratigraphic potential used to distinguish the Barremian from the lower Aptian. Lower Aptian beds also yield relatively advanced caprinid rudists.The Ökü?medere Formation is relatively thin, terrigeneous-rich, and rudist-free or rudist-poor in the Kurucasile sector, and thick, terrigeneous-poor, and rudist-rich from Amasra to Zonguldak, with a set of marker beds including either charophytes or Palorbitolina and capped by a coral unit underlying ammonite bearing marls. Terrigeneous-rich carbonates from the eastern sector are interpreted as marginal marine coastal, infralittoral environments and grade distally, northward, to marly basinal sediments. By contrast “Urgonian type” limestones from the Zonguldak-Amasra region possess a wide extent and no transition to coastal or basinal sediments has been observed. A transition from a typical platform westward to a mixed siliciclastic-carbonate ramp eastward was controlled by both the nature of the adjacent exposed area and tectonic factors affecting the overall continental margin that is a northward downwarping. The exposed area was flanked southward by a belt of coastal siliciclastics grading southward and eastward to deep water sediments of the Ulus basin. In mid-Bedoulian time, carbonate platform demise from the western region was drowned below deeper marly sediments whereas the eastern siliscilastic-carbonate ramp was buried below coastal clastics.     

Spatial distribution and assemblage structure of macrobenthos in a tidal creek in relation to industrial activities

The impact of petrochemical special economic zone activities on the health status of Jafari Creek was studied by assessing the changes in macroinvertebrate assemblages in nine sites during September 2006–January 2008. The relationship between spatial pattern of macroinvertebrate assemblages and ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, heavy metals contents) was measured. Background enrichment indices, contamination factor and contamination degree, were used to assess the health status in the study area based on nickel, lead, cadmium and mercury contents of the sediments. The macrobenthic communities had a low diversity and were dominated by opportunistic taxa. The BIO-ENV analysis identified salinity, dissolved oxygen, pH and silt/clay content of sediments as the major environmental variables influencing the infaunal pattern. This suggests that management should attempt to ensure minimal disturbance to environmental variables underlying the spatial variation in macroinvertebrate assemblages. Background enrichment indices showed that the health of Jafari Creek has declined over time due to the constant discharge of heavy metals to the Creek system. These indices also identified a significant degree of pollution in the study area. The decrease in the ecological potential of Jafari Creek was best highlighted by the alteration in macrobenthic assemblages.     

Reinterpretation of an archaeological pebble culture from the Middle Mekong River valley,Cambodia

In 1963, E. Saurin and J.‐P. Carbonnel discovered the Sre Sbov site on an alluvial terrace of the Mekong River in central Cambodia. Saurin described a lithic typology dating to the Lower/Middle Pleistocene from this site. Although the original lithic assemblage has been lost, this typology has been used continuously as a reference by Southeast Asian prehistorians. In 2007, a Khmer–French team conducted excavations at Sre Sbov that yielded numerous pebbles and cobbles showing apparently convincing handmade removals, as Saurin had previously described. However, an in‐depth study of this assemblage, combined with a geological survey of the area, led to the conclusion that the stones were, in fact, of natural origin, and that for this reason their typology should be disregarded. Using satellite imagery and geological surveys, we explain how such a misinterpretation may have occurred and define a “buffer zone,” corresponding to the maximal extent of the proto‐Mekong River, where fluvially reworked pebbles and cobbles resembling artifacts may be recovered. © 2009 Wiley Periodicals, Inc.     

Stochastic Modeling Approach for the Evaluation of Backbreak due to Blasting Operations in Open Pit Mines

Backbreak is an undesirable side effect of bench blasting operations in open pit mines. A large number of parameters affect backbreak, including controllable parameters (such as blast design parameters and explosive characteristics) and uncontrollable parameters (such as rock and discontinuities properties). The complexity of the backbreak phenomenon and the uncertainty in terms of the impact of various parameters makes its prediction very difficult. The aim of this paper is to determine the suitability of the stochastic modeling approach for the prediction of backbreak and to assess the influence of controllable parameters on the phenomenon. To achieve this, a database containing actual measured backbreak occurrences and the major effective controllable parameters on backbreak (i.e., burden, spacing, stemming length, powder factor, and geometric stiffness ratio) was created from 175 blasting events in the Sungun copper mine, Iran. From this database, first, a new site-specific empirical equation for predicting backbreak was developed using multiple regression analysis. Then, the backbreak phenomenon was simulated by the Monte Carlo (MC) method. The results reveal that stochastic modeling is a good means of modeling and evaluating the effects of the variability of blasting parameters on backbreak. Thus, the developed model is suitable for practical use in the Sungun copper mine. Finally, a sensitivity analysis showed that stemming length is the most important parameter in controlling backbreak.     

Shaping the Kuiper belt size distribution by shattering large but strengthless bodies

The observed size distribution of Kuiper belt objects (KBOs)—small icy and rocky Solar System bodies orbiting beyond Neptune—is well described by a power law at large KBO sizes. However, recent work by Bernstein et al. (2004, Astron. J. 128, 1364-1390) indicates that the size distribution breaks and becomes shallower for KBOs smaller than about 70 km in size. Here we show that we expect such a break at KBO radius ∼40 km since destructive collisions are frequent for smaller KBOs. Specifically, we assume that KBOs are gravity-dominated bodies with negligible material strength. This gives a power-law slope q?3 where the number N>r of KBOs larger than a size r is given by N>r∝r1−q; the break location follows from this slope through a self-consistent calculation. The existence of this break, the break's location, and the power-law slope we expect below the break are consistent with the findings of Bernstein et al. (2004, Astron. J. 128, 1364-1390). The agreement with observations indicates that KBOs as small as ∼40 km are effectively strengthless.     

Fate and biodegradability potential of an emerging micropollutant diclofenac in subsurface environment

The present study deals with the assessment of the fate of an emerging contaminant (diclofenac), present in the subsurface environment at specific concentration levels, and its biodegradation potential under different environmental configurations. Diclofenac is a widely consumed nonsteroidal anti-inflammatory drug used as a painkiller prescribed as pills or ointments and among the most frequently detected pharmaceuticals in wastewater treatment plants’ effluents. Fermentative/methanogenic cultures were enriched from previously contaminated sediment samples. Although partial biodegradation was achieved in all enrichment cultures, complete degradation was not observed. The results reflected that less than 6% of the diclofenac sorbed on the solid phase and the rest was either biotransformed (25–40%) or remained in the liquid phase (55–70%) at the end of 45-day incubation period. Although partial cometabolic degradation of diclofenac occurred in the presence of glucose, biodegradation was not observed in the presence of readily biodegradable carbon source (i.e., acetate). Diclofenac concentration up to 1000 µg/L did not affect the methanogenic activity of the enriched culture. The results of this study will have a significant impact in the designation of the permitted concentration limits of diclofenac before the discharge through wastewater treatment plants.     

USE OF REPLICATION AND SIGNAL-TO-NOISE RATIOS IN THE IDENTIFICATION AND ESTIMATION OF THE COMPOSITION OF LUBRICANT BASESTOCK MIXTURES USING ~(13)C NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY AND PROJECTION INTO PRINCIPAL COMPONENT/CANONICAL VARIATES SPACE

The theory of experimental error in analysis of mixture experiments by abstract factor analysis or targettransformation factor analysis is considered. The theoretical implications of using signal-to-noise ratios(as weights) or canonical variates analysis to reduce the level of imbedded error in the factor model areexamined. The approach is illustrated by application to ~(13)C NMR spectra of lubricant basestockmixtures.     

Why do we see the man in the Moon?

Numerical simulations and analysis show that the Moon locks into resonance with a statistical preference of facing either the current near-side or far-side toward Earth. The near-side is largely covered by dense, topographically low, dark mare basalts, the pattern of which to some, resembles the image of a man’s face. Although the Moon is locked in this configuration at present, the opposite one, with the current far-side facing Earth, is of lower potential energy and hence might be naively expected. Instead, we find that the probability of selecting each configuration depends upon the ratio of the asymmetry of the potential energy maxima, dominated by the octupole moment of the Moon, to the energy dissipated per tidal cycle within the Moon. If this ratio is small, the two configurations are equally likely. Otherwise, interesting dynamical behavior ensues. In the Moon’s present orbit, with the best-estimated geophysical parameters and dissipation parameter Q = 35, trapping into the current higher-energy configuration is preferred. With Q = 100 in analogy with the solid Earth, the current configuration is nearly certain. The ratio of energies and corresponding probabilities were different in the past. Relative crater counts on the leading and trailing faces indicate an impact may have unlocked the Moon before it settled into the present configuration. Our analysis constrains the geophysical parameters at the time of the last such event.     

Stratigraphy of Upper Cretaceous–Palaeogene sequences in the southern and eastern Menderes Massif (western Turkey)

The stratigraphy of the uppermost levels of the Menderes Massif is controversial and within its details lie vital constraints to the tectonic evolution of south-western Turkey. Our primary study was carried out in four reference areas along the southern and eastern Menderes Massif. These areas lie in the upper part of the Menderes metamorphic cover and have a clear stratigraphic relationship and contain datable fossils. The first one, in the Akbük-Milas area, is located south-east of Bafa Lake where the Milas, then KLzLla<aç and KazLklL formations are well exposed. There, the Milas formation grades upwards into the KLzLla<aç formation. The contact between the KLzLla<aç and the overlying KazLklL formation is not clearly seen but is interpreted as an unconformity. The Milas and KLzLla<aç formations are also found north of Mu<la, in the region of Yata<an and KavaklLdere. In these areas, the Milas formation consists of schists and conformably overlying platform-type, emery and rudist-bearing marbles. Rudists form the main palaeontological data from which a Santonian-Campanian age is indicated. The KLzLla<aç formation is characterized by reddish-greyish pelagic marbles with marly-pelitic interlayers and coarsening up debris flow deposits. Pelagic marbles within the formation contain planktonic foraminifera and nanoplankton of late Campanian to late Maastrichtian age. The KazLklL formation is of flysch type and includes carbonate blocks. Planktonic foraminifera of Middle Palaeocene age are present in carbonate lenses within the formation. In the Serinhisar-Tavas area, Mesozoic platform-type marbles (YLlanlL formation) belonging to the cover series of the Menderes Massif exhibit an imbricated internal structure. Two rudist levels can be distinguished in the uppermost part of the formation: the first indicates a middle-late Cenomanian age and the upper one is Santonian to Campanian in age. These marbles are unconformably covered by the Palaeocene-Early Eocene Zeybekölentepe formation with polygenetic breccias. In the Çal-Denizli area, the Menderes massif succession consists of cherty marbles and clastic rocks with metavolcanic lenses. The Lower-Middle Eocene zalvan formation lies unconformably on this sequence and is interpreted as equivalent to the marble horizons at Serinhisar but with pelagic facies. The zalvan formation consists of shale, mafic volcanic rock, lenses of limestone and blocks of recrystallized limestone. The zalvan formation is dated here for the first time by Early-Middle Eocene foraminifera and nanoplankton from the matrix of the formation. An angular unconformity exists between the Upper Cretaceous and Lower Tertiary sequences, suggesting that a phase of deformation affected the southern and eastern part of the Menderes Massif at this time. This deformation may be caused by initial obduction of the Lycian ophiolite onto the passive margin to the north of the Menderes carbonate platform during the latest Cretaceous. Drowning of the platform led to termination of carbonate deposition and deposition of deep water flysch-like clastic sediments.