Vol. 7 No. 1 (2007)
Articles
Abstract: Stratigraphy and lithology of the Avroman Formation (Triassic) were studied in Iraq and Iran. The study introduced new documentations about stratigraphy, lithology, fossil content and environment of deposition. Stratigraphically, it is very difficult to study the formation due to intense deformation, imbrication and even thrusting. However, it overlain by Qulqula Radiolarite Formation and Merga Red Beds in Iraq and Iran respectively while the underlying formation is not known as the lower boundary is not exposed. Lithologically, the formation consists mainly of pure limestone and no dolomite and marly limestone as previously mentioned. Microfacies include; grainstone, packstone and wackestone with association of oncoids, pelets, oolith and bioclasts. The fossils are relatively rare (except stromatolite or oncoids) and include gastropods, pelecypod green algae, echinoderms and forams. Environmentally, the formation was deposited in shallow isolated platform which was characterized by agitating warm normal marine water.
Abstract: Remotely sensed data especially satellite images contain noise in some cases for both types systematic and non-systematic. These noise represent by forms working to create problems in interpretation and analysis of remote sensing data. The non-systematic noise considered one of these problems because it appears by an random points in all parts of images and with different intensity of it surrounding areas. Therefore, the Non-systematic noise must be use active processing software to remove it, in order to avoid the effect on the other pixels which are not contain noise in the image. Oppositely, the systematic noise is shown by systematic frequently lines patterns, therefore it can been recognize and processing. The present study shows an active method for removing the non-systematic noise without change the other pixels. The suggested method is represented by a design of decision function depending on mixed filter, which is formed by merging the median filter and average filter depending on the thresholds value which used in comparism. The suggested method provided a good accuracy comparing with the classical methods, by removing the non-systematic noise without any pixel distortions of the original image.
Abstract: This study concentrates on two serpentinite bodies (Mawat and Penjwin) within Zagros Thrust Zone, North East Iraq. The Mawat Serpentinite which represents lherzolite protolith show δ18O of 6.77 – 8.33 %o and δD values of (-65) - (-61) %o. The Penjwin serpentinite (harzburgite protolith) show δ18O values of 10.90 – 13.29 %o and δD values of (-74) – (-69) %o. Mawat serpentinization occurred by hydration of mantle wedge rocks along intraoceanic supra-subduction zone at temperature of 150 – 200 oC. On the other hand Penjwin serpentinization occurred during and after emplacement of Penjwin ophiolite suite at temperature of 50 – 100 oC. Emplacement of Mawat serpentinite as an isolated body into Walash volcano-sedimentary sequence took place by diapiric process. Penjwin serpentinite was emplaced due to tectono-metamorphic event.
Abstract: At Beiji Refinery the level of ground water raised from 13m below ground surface to less than 1m within fifteen years. Number of boreholes was drilled to monitor the level and movement of ground water. Geophysical techniques (Seismic refraction and resistivity) have been used to detect subsurface cavities and channels in the refinery. It has been found number of subsurface cavities and holes most of them related to the presence of manholes and subsurface pipes and cables. The cavities are shallow (less than 5m deep) and had been formed due to the leakage water from these manholes and pipes which lead subsequently to the leaching of soil that is contain secondary gypsum. The most important result, however, which is not known before and lead to the clarification of ground water movement in the refinery is that the refinery had been built over a subsurface channel (old meander of Tigris river). This channel had been filled with river sediments (Pebbles, Sand, silt and clay). These sediments are presents as lentils. The direction of the subsurface channel is from east towards the west bending southwards, where the refinery had been built at the bending area where the thickness of the river sediments in this part is over 20m. It has been found that the water leakage from manholes and pipes are accumulating in the bending area where it forms as subsurface lake since it is the lowest part in the channel. From this area the water discharges to the southern refinery. The subsurface channel has been followed outside the refinery where it has been observed number of springs, cross-bedding and imbricate structures. An advice has been forward to the refinery to dig channels in the spring’s area to help discharging subsurface water.
Abstract: The biometric analysis on Miogypsina from bioclastic limestone (Azkand Formation) in Kirkuk area, Iraq reveals that the evolutionary trend based on a distinct overall change in morphology of the nepiont, which change is in agreement with the principle of nepionic acceleration as defined by Tan Sin Hok,1936. The oldest species of Miogypsinoides represented by Miogypsinoides complanata and Miogypsinoides formosensis accompanied by the association Miogypsina gunteri which exhibit in the lower part of Azkand Formation of Late Oligocene age (Chattian). The early Miocene association of Miogypsina s.s. represented by Miogypsina gunteri-tani are often accompanied by Miogypsinoides. Most of these are close to Miogypsinoides bantamensis
Abstract: Bulfat mafic intrusion was studied at Noba and Benas peaks at southeastern Hero at Qaladizeh area is located at the Zagros thrust fault. The studied rocks consist of troctolite, olivine gabbro, gabbro, amphibole pyroxene gabbro. In Noba peak the olivine gabbro is dominant rock while in Benas peak amphibole pyroxene gabbro is a dominant. Textural study reflected that Noba peak rocks had suffered tectonic deformation more than Benas peak rocks. The chemical composition of minerals changes from bottom to top as plagioclase from An60 to An57, olivine from Fo79 to Fo75 clinopyroxene from Wo46 En46 Fs8 to Wo47 En44 Fs9 of diopside type and amphibole Mg+2/(Mg+2 + Fe+2)x100 from 84 to 75. Benas peak plagioclase are An57, olivine changes from Fo59 to Fo53, clinopyroxene from Wo43 En42 Fs15 to Wo45 En39 Fs16 of (augite) type, amphibole Mg+2/(Mg+2 + Fe+2)x100 changes from 72 to 65. These changes reflected the control of crystal fractionation in creation of different rocks. In addition the Benas rocks represent more progressive stage of crystal fractionation. Benas rocks are rich in iron, titanium and vanadium and poor in chromium and nickel because of the governing of crystallization of olivine, Cr-spinel and clinopyroxene at earlier stages. Low ratios of strontium isotopes in Bulfat rocks indicate that it had been formed from magmas derived from upper mantle. Geochemical indication of elements and isotopes revel the variation in the degree of partial melting for source rocks. As Benas rocks formed from depleted source with a partial melting of more than 30% while Noba rocks formed from sources with partial melting of about 15%. Depending on the magmatic affinity, the studied rocks are classified to low-K calc-alkaline type associated with magma of Island arcs.
Abstract: Th age of the thick succession of 500m conglomerate and red claystone layers in the incised valleys at the lower part of Tanjero Formation at Chwarta area is estimated to be (1.23 m.y) duration. The age determination is achieved by Planktonic Foraminiferal biostratigraphic zonation which included the following Zones: Globotruncana aegyptiaca Interval Zone (CF8), Gansserina gansseri Interval Zone (CF7) Racemiguemblina fructicosa Interval Zone (CF4), Pseudoguembelina hariaensis Interval Zone (CF3) with missing zones of Contusotruncana contusa Interval zone (CF6) and Pseudotextularia intermedia Interval zone (CF5). Twenty six planktonic foraminiferal species and thirty benthonic foraminiferal species assigned to 33 genera have been recorded. The zonal scheme developed here is correlated with other sequences of Li and Keller (1998a) and d iscussed. e
Abstract: Previous studies considered Qulqula Conglomerate Formation and Qulqula Radiolarian Formation as two units that comprise Qulqula Group. They mentioned that the former formation overlies the later gradationally. The type sections of both formations occur at Kulkula Gorge, about 25 km to the northeast of Ranyia Town. These studies indicated the age Qulqula Conglomerate Formation as Albian-Cenomanian and referred to deposition in deep basin of high tectonic activity. This tectonic is punctuated by deposition of the wildflysch which is represented by 1200 m of conglomerate, sandstone and shale. However, during restudy of the lithology, stratigraphy and facies of Qulqula Conglomerate Formation at type section, any of the above characteristics are not observed. Conversely, many new data are recorded for the first time that revised lithology; stratigraphic position and age of the formation as concerned to previous ones. As it is shown the lithology of the formation is similar to the lithology of unit three of the Red Bed Series. This is proved by the following lines of evidence: Lateral tracing of the formation to the type locality of the Red Bed Series (Suwais village), indicating of their mergence with each other in a depositional condition near the village. Several species of Alveolina and Nummulite large forams are found in the gravels and boulders of the formation at the type locality. The age of these forams are Eocene; therefore the age of Qulqula Conglomerate Formation is changed to yonger than Eocene. The wildflysch facies as cited before is nothing except the molasse of Red Bed Series as it contains same alternation of lensoidal conglomerate and sandstone with some shale and claystone. This study suggests modification stratigraphical position of the formation in the type area so that it must be included in the Red Bed Series and Qulqulq Conglomerate Formation must be abandoned.
Abstract: Remote sensing data were employed to study the soil distribution of Late Quaternary deposits in Bashiqa Structure, north of Mosul City. The outcome of this study distinguished three primary classes of soils depending on their morphogenetic origin. Furthermore, the first two classes encompass five subclasses related to its particular site within the study area, and in which the geomorphological factor plays an important role in the spatial distribution of soil forms; thus providings the tools of soil classification distribution map at the scale of 1/50,000. The map produced is commensurable with the analysis of Landsat imagery at 1/100,000 scale, which resulted in the development of thematic image classified according to the relevant available computer programs. The separation of these classes accomplished through comparison of reflected spectrum of the optical pixels of the images with the spectral signature of each image pixels related to individual class. The integration and discussion of the results and documentation of the above mentioned classification were ascertained by field and laboratory examinations in order to verify the differences among these classes and to enhance the variability of spectral reflectance from one site to another.