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The Late Maastrichtian–Danian phosphatic succession prevails as a deposit to the west of Rutbah region, Western Iraq. This is manifested through the lithostratigraphic sections of boreholes (K.H5\6 and K.H 5\8) drilled previously in the area. The succession is mainly composed of phosphate, shale, porcelanite, oyster and foraminiferal carbonate lithofacies belonging to Digma and Akashat formations. Three facies associations are distinguished during the study: the phosclast planktonic (FA1) that dominates the outer ramp, the phosclast foraminiferal (FA2) that dominates the mid ramp, and the quartz dolomitic phosclast (FA3) present in the inner ramp. These facies’ associations are differentiated into seventeen microfacies types. Microfacies analysis and fauna contents have shown gradual facies variation grading from a high energy inner ramp environment in the east to a low energy deep water ramp environment in the west.

The core interval at the K.H5\6 and K.H5\8 wells in the west of Rutba province reveals a significant succession across the Late Cretaceous-Early Paleocene transition. The sampled interval encompasses a series of carbonates belong to Digma Formation of Latest Cretaceous age, which underlies the Akashat Formation of Danian age. Fifty-five species belong to thirty-five genera were recognized. Based on the distribution of these species, eight biozones were distinguished, three biozones are recorded from the K.H 5\6 studied section and two biozones are documented from the K.H 5\8 studied section which refers to Late Maastrichtian age of Digma Formation. Five biozones are recorded from Akashat Formation in the K.H 5\6 studied section and only one biozone is documented from the K.H 5\8 studied section which refers to Danian age. The depositional environment of the studied successions proposed it accumulated in the outer ramp environments.

In this research, the frequency-frequency interactions in chaotic systems has been experimentally and numerically studied. We have injected two frequencies on chaotic system where one of these frequencies is modulated with chaotic waveform and the other is untiled as a scanning frequency to find modulating frequency. It is observed that the Fast Fourier Transformation (FFT) peaks amplitude increased when the value of the two frequencies are matched. Thus, the modulating frequency could be observed, this leads to discover a new method to detect the modulating frequency without synchronization.

An integrated lithofacies and mineralogical assemblage was used to describe a depositional model and sequence stratigraphic framework of the Maastrichtian–Danian succession in the Western Desert of Iraq and eastern Jordan. Fifteen lithofacies types were grouped into three associations recognized in a distally steepened ramp characterized by an apparent, distinct increase in a gradient paleobathymetric deepening westward. The clay and nonclay minerals are dominated by smectite and palygorskite, with trace amounts of kaolinite, sepiolite, illite and chlorite. Meanwhile, quartz, calcite, dolomite, opal CT (Cristobalite - Tridymite), and apatite are the main nonclay minerals. The widely dominated smectite in the Western Phosphatic Basin of Iraq (WPB) refers to warm, subhumid climates and low topographic relief in the source area, which increased significantly with transgressive cycles. In contrast, the palygorskite was generated under seasonal semiarid/arid climates associated dominantly with regressive cycles. Five sequence boundaries are documented in the present study according to hiatus, erosional surfaces, Thalassinioides burrows, reworked fauna, and extensively bored hardground. These sequence boundaries separate the studied sequences into four third-order depositional sequences correlated to their regional and global counterparts. The combined effects of the local tectonic activity of the Rutbah High and sea-level drops are amalgamated inside the Western Desert of Iraq and eastern Jordan because of a long-time gap, particularly across the Cretaceous/Paleogene (K/Pg) and Danian/Selandian (Da/Se) transitions.

This petrographic and petrophysical study constrains parameters controlling porosity-permeability heterogeneity in unconventional microporous lime mudstones reservoir of the Lower Bab Member (Aptian) deposited in intrashelf Bab basin, Abu Dhabi, United Arab Emirates. Depositional texture and diagenetic processes control the petrophysical properties of the mudstones. The high concentration of coccoliths with relatively large intragranular pores causes increase in porosity and permeability. Diagenetic control on reservoir quality includes the degree of development and thickness of syntaxial micro-overgrowths around the micrite particles. Mudstones with well-developed and coalesced overgrowths, which are most common in the vicinity of stylolites, have the lowest porosity (5–8%) and permeability (0.01–0.1 mD) and narrowest pore throats (around 0.05 μm). Conversely, mudstones with relatively poorly developed syntaxial calcite micro-overgrowths have greater porosity (20–24%), permeability (0.3–2 mD) and pore-throat size (0.5 μm). Scattered moldic pores formed by the dissolution of aragonitic bivalves caused increase in porosity but not permeability of the wackestones. Combining petrographic and petrophysical properties revealed that depositional parameters and diagenetic processes resulted in three distinct unconventional microporous lime mudstone reservoir types.

The Ordovician-Silurian hot shales are proved to be source for hydrocarbon in Akkas Field. New set of core samples of these important strata from Khabour and Akkas formations were examined from Akkas-1 well by organic petrography. The core samples of the Ordovician were found to be enriched in the liptinitic macerals that are mostly telalginite and lamalginite with lower abundances of vitrinite-like, inertinite and non-fluorescing network-forming matrix bituminite macerals. The studied Ordovician samples showed organic matter composition with large liquid hydrocarbon generation potentiality. The telalginite grains belong to the mat-forming algae that are found mostly in clusters and colonies. The early colonies are assigned to the Ordovician cosmopolitan Gloeocapsomorpha cyanobacterium. Several morphological variations in the telalginite particles are noticed through time that verifies their evolution. This is first record of this important oil prone organic matter in this region. In addition, unique micro-laminae are identified and attributed to the record of seasonal changes or varves. These varves indicate the summer/winter cyclic changes accompanied the Late Ordovician glaciation at western part of Arabian Peninsula and its influence on sedimentation in nearby basins. This cyclic pattern is also recorded for the first time as glaciation evidence in the Akkas-1 well. The seasonal changes of the summer/winter cycle are accompanied with some distinctions in the quantity and quality of the telalginite particles. The summer micro-laminae have large abundance of both organic matter and liptinite maceral. The Silurian hot shale has abundant liptinite maceral that are mostly bituminite and lamalginite. In addition, they are rich in redox sensitive trace elements that reveal anoxic depositional conditions. Ultralaminar structures are documented for the time in the bituminite of Silurian shale, which suggest a micro-algal origin. The source rock in the Silurian shale has a large potentiality to generate liquid hydrocarbon.

With the long-term aim of enhancing the binding properties of dinuclear RuII-based DNA light-switch complexes, a series of eight structurally related mono- and dinuclear systems are reported in which the linker of the bridging ligand has been modulated. These tethered systems have been designed to explore issues of steric demand at the binding site and the thermodynamic cost of entropy loss upon binding. An analysis of detailed spectroscopic and isothermal titration calorimetry (ITC) studies on the new complexes reveal that one of the linkers produces a dinuclear systems that binds to duplex DNA with an affinity (Kb > 107 M-1) that is higher than its corresponding monometallic complex and is the highest affinity for a non-threading bis-intercalating metal complex. These studies confirm that the tether has a major effect on the binding properties of dinuclear complexes containing nintercalating units and establishes key design rules for the construction of dinuclear complexes with enhanced

In this work we try to clarify, and correlate between two Maastrichtian aged units, namely Digma and Safra Units from selected sections in western desert of Iraq. Taking in consideration the stratigraphic code of NASCENT (2005), and the results of previous studies, nine criteria have been used for the correlation, as follow: 1- From lithostratigraphic point of view, Digma Formation (Fm.) mostly composed of dark grey to blackish gray, uniform Carbonates-dominated facies, while Safra unit is characterized by light yellowish brown mixed phosphatic- siliceous-siliciclastics and carbonates facies. 2- Digma Fm. is characterized by Benthonic foraminifera assemblages (Bulimmina sp., Siphogerinoides sp. & Bolivinoides sp. ), while Safra phosphatic unit is flourished by macrofossils assemblages and vertebrates (Oyster, fish teeth’s and bones). 3- The upper and lower boundaries of the Digma Fm. are conformable, and vice versa for Safra Unit. 4- Illite/Semctite mixed layers-Illite clays assemblage and Glauconitic are predominates in Digma Fm., while Sepiolite-palygorskite-Montmorillonite, are common in Safra Unit, without any Glauconitic mineralization. 5- Digma Fm. slightly influenced by neomorphism and micritization. On other hand, Safra facies extremely influenced by phosphatization, silicification, dolomitization, and neomorphism and carbonate-silica replacement of the original evaporate minerals. 6- The predominated foraminiferal wackestone and mudstone microfacies, within Digma facies associations, mostly indicate deep trough marine condition (Anah Graben). The mixed phosphatic-carbonates (Oyster coquina band) and siliciclastics facies, (occasionally cross laminated), mostly deposited in shallower water depth, on the Arabian platform and distal steepened ramp towards Rutba flanks. 7- Sequence boundary of type one and three is bounded the Safra Unit respectively from upper and lower parts. 8- Continuously deposited Sequence was detected from the parasequences of the Safra facies, and across Maastrichtian/Danian boundary (Trafawi Unit). 9- The paleo-configuration of the basin almost influenced by the reactivity of the Anah basement faults started in the Late Campanian, and combined by shallowing upwards sequences. The conclusion is that, Digma facies can be considered as local facial changes of the Shiranish Formation, while Safra unit can be considered as a lower Member of (L. Maastrichtian-Danian) Jeed Formation, which is coincides with the whole stratigraphic frame work of the Mediterranean segments of the Tethyan phosphatic realm.

I2CITC allows the analysis of isothermal titration calorimetry (ITC) data for complex coupled equilibria. Here we describe how, using I2CITC, ITC data for systems involving a self-aggregating ligand and a host offering one or two binding sites can be analyzed, how interaction models can be tested, and how confidence intervals for the optimized parameters can be determined.

I2CITC allows the analysis of isothermal titration calorimetry (ITC) data for complex coupled equilibria. Here we describe how, using I2CITC, ITC data for systems involving a self-aggregating ligand and a host offering one or two binding sites can be analyzed, how interaction models can be tested, and how confidence intervals for the optimized parameters can be determined.

Carbonaceous calcitic chalk from a 50-m stratigraphic sample interval (n = 35) of the Maastrichtian-Danian Muwaqqar Chalk Marl (MCM) Formation, Jordan, has elevated concentrations of biophile and/or redox-sensitive trace metals (Mo, Ni, V, U, Cr, Cd, Ag, Se, and P) which indicate enhanced paleo-bioproductivity, biodegradation and remineralization under reducing conditions. Very low concentrations in Mn and Ba suggest a relatively open system for components mobile under reducing conditions. The last 800,000 years to the K/Pg boundary are not exposed in Jordan, but the stratigraphic 20-m-interval below and above the hiatus of the K/Pg transition (n = 8) with 2.6 ± 1.8 wt% organic C is particularly metal-enriched with average bulk-rock contents of 132 ppm Mo, 177 ppm Ni, 363 ppm V, 576 ppm Zn, 39 ppm Se, 1.4 ppm Ag, 106 ppm Cd, 474 ppm Cr. These concentrations are dominantly of authigenous origin, when normalized to PAAS, i.e. 100 % Mo, 100% Ag, 100% Cd, 96% Cr, 95% Ni, 95% Zn, 80% V authigenous, and testify to ≥90% of biodegradation of planktonic debris by anaerobic bacterial activity at or near the seafloor. The depositional environment is euxinic, and Mo/TOC ratios from

Ordovician-Silurian black shales are the source rocks in the Palaeozoic petroleum system in Iraq. However, their source and depositional conditions from their mineralogy and inorganic geochemistry are quite lacking in previous works. These shales also provide an opportunity to examine the changes in paleoenvironment, paleoclimate and paleoredox conditions across the Ordovician-Silurian transition. The Ordovician black shales comprise of kaolinite, illite, chlorite, quartz, dolomite, calcite, and traces of feldspars and siderite, while the Silurian black shales comprise of illite, quartz, calcite, dolomite and pyrite. Calculated SiO2 (wt %) and Al2O3/TiO2 ratios suggest felsic source rocks for the Ordovician black shales and intermediate source rocks for Silurian hot shales. The shallow marine setting for the Ordovician black shales that changed to a deeper environment during the Silurian time was interpreted from the V, P2O5, and Al2O3 diagrams is consistent with the abundance of trace fossils Monocraterion sp., Cruziana problematica, Diplichnites sp., and Skolithos sp. which refer to proximal shallow marine conditions and abundance of graptolites monograptus in the Silurian black shales, which refer to an open-marine environment. Paleoredox indicators such as TOC and Mn contents as well as Ni/Co, V/Ni, U/Th, and V/Cr ratios prove fluctuation of redox conditions from oxic in the Ordovician shales to anoxic in the Silurian black shales. Late Ordovician glaciation in Iraq can be indicated from the low values of chemical index of weathering (CIA = 52-58) in the samples from the upper part of the upper part of the Khabour Formation that refer to cold and arid climate conditions that prevailed during the late Ordovician time. Abundance of extrabasinal and poor-sorted mud clasts in this interval might support the glaciogenic origin of this part. The black shales in the Khabour Formation is considered as fair source rock (average TOC = 0.9 wt%), while that in the Akkas Formation is an excellent source rock (average TOC = 13.2 wt%) for hydrocarbon generation. Kerogen in the Ordovician and Silurian black shales were derived from marine organic matter as indicated by the binary plot and total C1-C15-n-C6-n-C14-n-C15+ ternary diagram. Organic matter in the Ordovician black shales is highly matured compared to that in the Silurian black shales due to higher illite crystallinity (IC) values in the Ordovician (0.61–0.75° D2θ) relative to that in the Silurian (0.45–0.55° D2θ) black shales.

Using a new mononuclear “building block,” for the first time, a dinuclear RuII(dppn) complex and a heteroleptic system containing both RuII(dppz) and RuII(dppn) moieties are reported. The complexes, including the mixed dppz/dppn system, are 1O2 sensitizers. However, unlike the homoleptic dppn systems, the mixed dppz/dppn complex also displays a luminescence “switch on” DNA light-switch effect. In both cisplatin sensitive and resistant human ovarian carcinoma lines the dinuclear complexes show enhanced uptake compared to their mononuclear analogue. Thanks to a favorable combination of singlet oxygen generation and cellular uptake properties all three of the new complexes are phototoxic and display potent activity against chemotherapeutically resistant cells.