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The main aim of this research is to define the mineralogical composition of recent sediments deposited around the Al-Teeb river basin in eastern Missan, trying to determine the provenance or the source of these sediments. The study area represents the southeastern edge of the Mesopotamian Plain and is part of it. Quaternary deposits cover most of the area. It is clayey with old sea and river deposits and part of aeolian deposits. These sediments cover 95% of the study area, while the older rocks, which date back to the Tertiary (Late Miocene – Pliocene), exposed in the area east and northeast of the Al-Teeb area, made up hills which back to the undifferentiated Pliocene Mukdadiya and Bai-Hassan formations. The light components of these sediments consist mainly of quartz, feldspars (potash and plagioclase feldspar), sedimentary rock fragments (carbonate rock fragments, chert rock fragments, evaporates fragments), igneous rock fragments, and metamorphic rock fragments The heaviest minerals are opaque, amphiboles, pyroxenes, chlorite, epidotes, biotite, garnet, muscovite, zircon, kyanite, staurolite, and rutile. These sediments are typically formed by sedimentary rocks (single or many cycles), low and high-rank metamorphic rocks, acidic and basic igneous rocks, and pegmatite rocks. The high percentage of opaque heavy minerals in clastic sediment refers to unstable clastic sediments. The stability issue to the areas during the study shows that there are significant variances over the several places, indicating dissimilar sources and types of source rocks

The superior thermal and optical properties of transparent polycrystalline ceramics make them attractive alternatives to glass-based materials for laser gain media. Fibers have other advantages of compactness, vibration-resistance, and reduced cooling requirements. Recently it was found that surface roughness caused by grain boundary grooving dominated optical scattering even though there were other scattering sources in the fiber. Therefore, a lot of effort went to fabrication of fibers with smooth surfaces. A mechanical polishing method for polycrystalline YAG fibers was developed. The fiber surface roughness was reduced, while maintaining a circular cross-section. Surface-polished 1.5% Ho-doped polycrystalline YAG fiber, 62 mm long with 31 μm diameter, was fabricated, and lasing was demonstrated from this fiber. Effects of surface-polishing on the surface roughness and scattering coefficient are presented, and lasing characteristics are discussed.

A polycrystalline 1.5% Ho: YAG fiber with a diameter of 31 µm was prepared. Surface roughness from grain boundary grooving was reduced by polishing, which decreased the fiber scattering coefficient from 76 msup-1/supto 35 msup-1/sup. Lasing tests were done on this fiber with a SF57 Schott glass cladding. Lasing was confirmed by spectrum narrowing with threshold pump power lower than 500 mW and a slope efficiency of 7%. To our knowledge, this is the first lasing demonstration from a small diameter polycrystalline ceramic fiber.