Thesis (M.A.)--al-Maʻhad al-ʻĀlī lil-Dirāsāt al-Islāmīyah, Bayrūt, 1984. / Includes bibliographical references (p. 407-416).

Five outcrop sections (Wadi Mi'aidin, Wadi Bani Kharus, Jebel Madar, Jebel Madamar and Jebel Salak), exposing Thamama and Wasia Group sediments were sedimentologically logged and sampled. Thin sections of each of the Thamama Group samples were prepared for micropalaeontological and microfacies analysis. The foraminifera, calcareous algae and calpionellids in each sample were recorded in order to provide a means of biostratigraphic subdivision, and together with microfacies analysis and sedimentological observations made in the field, provide a means of elucidating the depositional environments of the Thamama Group in the study area. Correlation between outcrop sections has been attempted using a biozonation scheme developed in the course of this project, and also by graphic correlation techniques. The taxonomy of 39 genera including 56 species of key foraminifera, calcareous algae and calpionellids is reviewed in detail. A complete revision of Cretaceous Middle Eastern lithostratigraphic nomenclature is required. Some recommendations for such a revision are proposed. Within the Thamama Group, 13 biozones/subzones are recognised using the extinction and inception events for key taxa. Both biozonal correlation and graphic correlation demonstrate that most Thamama Group formations are diachronous and may also be condensed at some localities. Biostratigraphic studies demonstrate that in the Central Oman Mountains region the Thamama Group formations are of the following ages: The Rayda Formation is of Early Berriasian age. It possibly extends into the earliest Valanginian at some localities (eg. Wadi Bani Kharus). The Salil Formation is of Berriasian - Valanginian age, possibly Hauterivian in age in its upper part at some localities. The Habshan Formation is of Hauterivian age everywhere, with possible extension into the Late Valanginian in its IOWCT part The Lekhwair Formation is essentially of Hauterivian - Barremian age (often largely Hauterivian). The Kharaib Formation is of typically Late Barremian - Early Aptian age, whilst the Shuaiba Formation is of Early Aptian age. Thamama Group deposition took place on an initially downwarped carbonate ramp, prograding towards the Tethyan Ocean (towards the north and east). Offshore palaeowinds precluded the development of reefs, but an oolitic shoal was located at the margin of the ramp, at least during Hauterivian times.

Zugl.: Kassel, Univ., Diss., 2007

Thesis (M.A.)--al-Maʻhad al-ʻĀlī lil-Dirāsāt al-Islāmīyah, Bayrūt, 1984. / Includes bibliographical references (p. 407-416).

Zugl.: Tübingen, Univ., Diss.

Northern Oman is an arid area almost entirely dependent upon groundwater recharged by highly sporadic rainfall. Precipitation estimates are hampered by a lack of any reliable altitude-rainfall relationship. Below 700 m there is no statistically significant relationship. The isotopic composition of groundwater is strongly influenced by the rainfall amount (related to storm frequency), and not just by altitude/temperature. Storm events with long return periods are of disproportionate importance to recharge. Despite the huge volume of carbonate formations, holokarstic development is generally immature, and groundwater storage is greatest in alluvial piedmont surrounding main limestone massifs. Isotopes, chemistry and hydrologic measurements show that post-storm evaporative losses are very large. The origin of limestone springs and their chemical and physical anomalies are described. Structure rather than petrology controls groundwater flow in the limestones, hence regional differences in structural style produce contrasting hydrologic regimes between the various massifs. The Semail nappe mantle sequence is the only other hard-rock formation of groundwater significance. Though much less productive than the carbonates, these ultramafics display extraordinary chemical activity, yielding bicarbonate waters from the weathered zone, whilst more deeply circulating groundwaters produce hyperalkaline springs by low-temperature serpentinisation. Associated processes include solute reduction, hydrogen evolution, hydroxide and carbonate precipitation, hydroxide-basic rock reaction, salt enrichment and water-rock isotopic exchange. Throughout the interior catchments, groundwater mostly flows into narrow buried alluvial channels which are often constricted at hard-rock nodal points, thus facilitating very efficient interception and recovery by the "falaj" system. Traditional agriculture has evolved to cope with fluctuating groundwater supply but is sensitive to increased abstraction. On the Batinah plain, greatly increased coastal abstraction has locally induced moderate to severe salinisation. Existing process studies are insufficiently quantified to provide the resolution necessary to manage groundwater resources, especially in high-risk coastal areas.

Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished

This dissertation examines four specific aspects of capital structure and dividend policy. The first issue concerns the determinants of capital structure dynamics. The primary objective is to examine whether stock returns are important factors in firm???s capital structure choice, and if so, whether this effect is persistent. In so doing, we use a data set which (1) avoids the complexity of tax rates faced by previous studies, (2) we introduce new variables that are unique to Oman, and (3) we distinguish empirically between bank debt and non-bank debt. We find stock returns are a first order determinant of capital structure. Firms do show some tendency to rebalance towards their target capital structure. However, the impact of stock returns dominates the effects of rebalancing. We also find new evidence that firms do take countermeasures to offset changes in their leverage that stem from equity value variations, but do so at a low speed. The next topic studied concerns the ex-dividend day behaviour. We investigate this issue using a unique data set where there are no taxes on dividends and capital gains and stock prices are decimalized. In this economy, any price decline that is smaller than the dividends can not be attributed to taxes and price discreteness. We find that the stock price drops by less than the amount of dividends and there is a significant positive ex-day return. We are able to account for our results using market microstructure models. The third issue investigated is the stock price reaction to dividend announcements. Tax-based signaling models argue that dividends would not have information and be informative if it is not for the higher taxes on dividends relative to capital gains that they apply to shareholders. The absence of personal taxes in Oman presents a valuable opportunity to test this prediction. Our results show that the announcements of dividend increases (decreases) are associated with a stock price increase (decrease) which contradicts the tax-based signaling models. The final chapter analyzes the determinants and stability of dividend policy of financial and non-financial firms. Investigating this issue is important for at least two reasons. First, Omani firms distribute almost 100% of their profits in dividends which led the Capital Market Authority (CMA) to issue a circular (number 12/2003) arguing that firms should retain some of their earnings for ???rainy days???. This allows us understand the characteristics of firms that pay dividends. Second, firms are highly levered mainly through bank loans which render the role of dividends in reducing the agency costs less important. Unlike most previous studies, we include both dividend paying and non-dividend paying firms to avoid a selection bias. We find that there are some common factors that determine dividend policy of both financial and non-financial firms and there are some factors that affect only non-financial firms. We also find that the factors that influence the probability to pay dividends are the same factors that drive the amount of dividends paid for both financial and non-financial firms. We document that non-financial firms adopt a policy of smoothing dividends while financial firms do not have a stable dividend policy.

This dissertation examines four specific aspects of capital structure and dividend policy. The first issue concerns the determinants of capital structure dynamics. The primary objective is to examine whether stock returns are important factors in firm???s capital structure choice, and if so, whether this effect is persistent. In so doing, we use a data set which (1) avoids the complexity of tax rates faced by previous studies, (2) we introduce new variables that are unique to Oman, and (3) we distinguish empirically between bank debt and non-bank debt. We find stock returns are a first order determinant of capital structure. Firms do show some tendency to rebalance towards their target capital structure. However, the impact of stock returns dominates the effects of rebalancing. We also find new evidence that firms do take countermeasures to offset changes in their leverage that stem from equity value variations, but do so at a low speed. The next topic studied concerns the ex-dividend day behaviour. We investigate this issue using a unique data set where there are no taxes on dividends and capital gains and stock prices are decimalized. In this economy, any price decline that is smaller than the dividends can not be attributed to taxes and price discreteness. We find that the stock price drops by less than the amount of dividends and there is a significant positive ex-day return. We are able to account for our results using market microstructure models. The third issue investigated is the stock price reaction to dividend announcements. Tax-based signaling models argue that dividends would not have information and be informative if it is not for the higher taxes on dividends relative to capital gains that they apply to shareholders. The absence of personal taxes in Oman presents a valuable opportunity to test this prediction. Our results show that the announcements of dividend increases (decreases) are associated with a stock price increase (decrease) which contradicts the tax-based signaling models. The final chapter analyzes the determinants and stability of dividend policy of financial and non-financial firms. Investigating this issue is important for at least two reasons. First, Omani firms distribute almost 100% of their profits in dividends which led the Capital Market Authority (CMA) to issue a circular (number 12/2003) arguing that firms should retain some of their earnings for ???rainy days???. This allows us understand the characteristics of firms that pay dividends. Second, firms are highly levered mainly through bank loans which render the role of dividends in reducing the agency costs less important. Unlike most previous studies, we include both dividend paying and non-dividend paying firms to avoid a selection bias. We find that there are some common factors that determine dividend policy of both financial and non-financial firms and there are some factors that affect only non-financial firms. We also find that the factors that influence the probability to pay dividends are the same factors that drive the amount of dividends paid for both financial and non-financial firms. We document that non-financial firms adopt a policy of smoothing dividends while financial firms do not have a stable dividend policy.

The aim of this investigation was to develop an Adjustment Assessment Instrument for Omani College Students. The adjustment instrument items were constructed and grouped into academic, family, social and personal adjustment areas common to Omani college students. The content validity of the adjustment instrument was determined by utilizing two Delphi panels. The first panel examined the instrument items which represented Omani students' adjustment areas. The second panel determined the instrument items' content domains and the appropriateness of their dimensions. The revised 190 item instrument was administered to 30 Omani Students at Sultan Qaboos University (SQU) in order to test the wording of the items and determine the actual time for the completion of the instrument. One item was dropped from the instrument leaving 189 items, including 70 positive and 119 negative items. The developed adjustment instrument was administered to 400 Omani students at SQU. Internal consistency reliability and test-retest reliability for the developed instrument were investigated. The test-retest reliability was determined by administering the instrument to 37 subjects using two week intervals between the two tests. In addition to reliability consideration, construct validity was determined by examining (a) instrument dimensionality, (b) factor analysis, (c) item analysis, and (d) internal consistency. The results revealed that the developed adjustment instrument possessed high reliability estimation which was adequate for individual measurement. In addition, the results supported the construct validity of the instrument as an adjustment measure. The results of the correlation matrix of the developed four dimensions and of the inter-factor correlation of the adjustment questionnaire provided evidence for the multidimensionality of the instrument. Also, factor analysis results confirmed that the developed instrument consisted of four dimensions: academic, family, social and personal adjustment. Moreover, item-total correlation finalized the instrument, which included 58 items, of which 25 were positive and 32 negative. These items were retained as adjustment item statements for the final Adjustment Instrument for College Students. The results of the internal consistency measurements provided additional support for the construct validity of the final adjustment instrument. / Graduation date: 1997