Petroleum geological characteristics and exploration targets of the oil-rich sags in the Central and West African Rift System

Based on seismic,drilling,and source rock analysis data,the petroleum geological characteristics and future exploration direction of the oil-rich sags in the Central and West African Rift System(CWARS)are discussed.The study shows that the Central African Rift System mainly develops high-quality lacustrine source rocks in the Lower Cretaceous,and the West African Rift System mainly develops high-quality terrigenous organic matter-rich marine source rocks in the Upper Cretaceous,and the two types of source rocks provide a material basis for the enrichment of oil and gas in the CWARS.Multiple sets of reservoir rocks including fractured basement and three sets of regional cap rocks in the Lower Cretaceous,the Upper Cretaceous,and the Paleogene are developed in the CWARS.Since the Late Mesozoic,due to the geodynamic factors including the dextral strike-slip movement of the Central African Shear Zone,the basins in different directions of the CWARS differ in terms of rifting stages,intervals of regional cap rocks,trap types and accumulation models.The NE-SW trending basins have mainly preserved one stage of rifting in the Early Cretaceous,with regional cap rocks developed in the Lower Cretaceous strata,forming traps of reverse anticlines,flower-shaped structures and basement buried hill,and two types of hydrocarbon accumulation models of"source and reservoir in the same formation,and accumulation inside source rocks"and"up-source and down-reservoir,and accumulation below source rocks".The NW–SE basins are characterized by multiple rifting stages superimposition,with the development of regional cap rocks in the Upper Cretaceous and Paleogene,forming traps of draping anticlines,faulted anticlines,antithetic fault blocks and the accumulation model of"down-source and up-reservoir,and accumulation above source rocks".The combination of reservoir and cap rocks inside source rocks of basins with multiple superimposed rifting stages,as well as the lithologic reservoirs and the shale oil inside source rocks of strong inversion basins are important fields for future exploration in basins of the CWARS.

The Regional Climate Effects of Replacing Farmland and Re-greening the Desertification Lands with Forest or Grass in West China

The West Development Policy being implemented in China causes significant land use and land cover (LULC) changes in West China, of which the two most important types of LULC change are replacing farmland and re-greening the desertification land with forest or grass. This paper modifies the prevailing regional climate model (RCM) by updating its lower boundary conditions with the up-to-date satellite database of the Global Land Cover Characteristics Database (GLCCD) created by the United States Geological Survey and the University of Nebraska-Lincoln. The modified RCM is used to simulate the possible regional climate changes due to the LULC variations. The preliminary results can be summarized as that the two main types of LULC variation, replacing farmland and greening the desertification lands with forest or grass in west China, will affect the regional climate mostly in northwest and north China, where the surface temperature will decrease and the precipitation will increase. The regional climate adjustments in South, Southwest China and on the Tibet Plateau are uncertain.

The Statistical Significance Test of Regional Climate Change Caused by Land Use and Land Cover Variation in West China

The West Development Policy being implemented in China is causing significant land use and land cover （LULC） changes in West China. With the up-to-date satellite database of the Global Land Cover Characteristics Database （GLCCD） that characterizes the lower boundary conditions, the regional climate model RIEMS-TEA is used to simulate possible impacts of the significant LULC variation. The model was run for five continuous three-month periods from 1 June to 1 September of 1993, 1994, 1995, 1996, and 1997, and the results of the five groups are examined by means of a student t-test to identify the statistical significance of regional climate variation. The main results are： （1） The regional climate is affected by the LULC variation because the equilibrium of water and heat transfer in the air-vegetation interface is changed. （2） The integrated impact of the LULC variation on regional climate is not only limited to West China where the LULC varies, but also to some areas in the model domain where the LULC does not vary at all. （3） The East Asian monsoon system and its vertical structure are adjusted by the large scale LULC variation in western China, where the consequences are the enhancement of the westward water vapor transfer from the east oast and the relevant increase of wet-hydrostatic energy in the middle-upper atmospheric layers. （4） The ecological engineering in West China affects significantly the regional climate in Northwest China, North China and the middle-lower reaches of the Yangtze River; there are obvious effects in South, Northeast, and Southwest China, but minor effects in Tibet.

Sexual Risk Behaviours among People Living with HIV and Implications for Control in the North West Region of Cameroon

In Cameroon, despite extensive control efforts against HIV/AIDS, the number of new HIV infections is still on the rise. The factors contributing to this are not clearly understood. We hypothesized that it may lie on people living with HIV (PLHIV). In a case-control descriptive study, we studied the characteristics and sexual risky behaviour of PLHIV in the North West Region of Cameroon which has the highest HIV prevalence. Participants were screened for HIV and a structured questionnaire was used in data collection. An equivalent number (350) of PLHIV and controls who did not differ with respect to age and sex participated. Relative to the control, PLHIV were generally less educated (P < 0.001), poorer and less privileged (P < 0.001) with no stable source of income. Among participants that were once married, a greater proportion of PLHIV were divorced (OR = 5.23, P = 0.007), and widows (OR = 2.73, P = 0.001). Among participants that were single, a relatively greater proportion of PLHIV practiced multi-partner sex (OR = 4.55, P< 0.001). History of STDs was higher in PLHIV than the control (OR = 1.88, P = 0.001). Out of 350 PLHIV, 280 (80%) admitted to having had sexual intercourse after being diagnosed of which only 127 (41.78%) admitted to using condoms and 132 (47.14%) admitted to concealing their HIV status from their sexual partner(s). These findings have implications in HIV control programs which should target the poor and the less educated, as well as the sexual behaviour of PLHIV, so as to reverse the current rising trend of new infections in the country.

Interpretation of the west segment of the coastal fault zone in the coastal region of South China based on the gravity data

By systemic processing, comprehensive analysis, and interpretation of gravity data, we confirmed the existence of the west segment of the coastal fault zone(west of Yangjiang to Beibu Bay) in the coastal region of South China. This showed an apparent high gravity gradient in the NEE direction, and worse linearity and less compactness than that in the Pearl River month. This also revealed a relatively large curvature and a complicated gravity structure. In the finding images processed by the gravity data system, each fault was well reflected and primarily characterized by isolines or thick black stripes with a cutting depth greater than 30 km. Though mutually cut by NW-trending and NE-trending faults, the apparent NEE stripe-shaped structure of the west segment of the coastal fault zone remained unchanged,with good continuity and an activity strength higher than that of NW and NE-trending faults. Moreover,we determined that the west segment of the coastal fault zone is the major seismogenic structure responsible for strong earthquakes in the coastal region in the border area of Guangdong, Guangxi, and Hainan.

Mantle/Crust Evolution and Eco-Environmental Effects as Exemplified by Zhangjiakou-West Beijing Region

The living circumstances of human beings are closely related to the geological environment. As exemplified by the Zhangjiakou-West Beijing region, this paper describes the intensive mantle-crust uplift, which led to anomalous element background values for regional rocks (ores) and soils. As a result, some agricultural crops, and forests and fruits are of “super-quality and high yield” or of “poor quality and low yield”. The anomalous elements can find their way into grains, fruits, vegetables and drinking water and then will be taken by human beings, constituting a food chain, which would directly impact human health and lead to the spread of some endemic diseases. Studies have shown that the geomorphological features in the Zhangjiakou-West Beijing region are the outcome of geotectonic evolution since the Mesozoic. Mantle-crust movement is the key factor leading to the evolution and change of the regionally geological environment.

Comparative Research on the Economic Development of Xinjiang i n the Perspective of Development of the West Regions

In the context of Development of the West Regions, by using the annual data from 1999 to 2009 in whole China and 12 provinces of the western regions, we analyze the achievements of socio-economic development of Xinjiang Uygur Autonomous Region from 1999 to 2009 as follows: the economic aggregate has increased prominently and the growth rate is increasing ceaselessly; the primary industry, secondary industry and tertiary industry develop evenly, and the industrial structure is incessantly optimized; the quality of economic growth is promoted increasingly and the living standard of people is improved greatly; the primary industry, secondary industry and tertiary industry stride in tandem, and the momentum of growth is strong. We conduct horizontal comparison on the main economic indicators of Xinjiang, 12 provinces of the western regions and whole China, which include GDP and its growth rate, investment of fixed assets, structure of the primary industry, secondary industry and tertiary industry, the industrial added value, GDP per capita, gross retail sales of social consumption, export and import trade, net income per capita of peasants and herdsmen, and general budget revenue. The result shows that although the implementation of the strategy of Development of the West Regions and the economic development of Xinjiang have achieved some remarkable results, there is a conspicuous gap in comparison with the expected effect. The problems existing in the operation of Xinjiang's economy are analyzed as follows: the industrial level is low, and the economic growth mode is yet to be transformed; the disposable income per capita of urban residents grows slowly, and the increasing gap between the urban areas and rural areas has no trend of dwindling; the investment aggregate is very low, and the momentum of economic growth is short. In order to make the central government and 19 provinces and cities offer pointed aid for Xinjiang, promote the implementation of new strategic development of Western China, and promote the better economic development of Xinjiang in the period of the Twelfth Five-Year Plan, we put forward some feasible suggestions as follows: Xinjiang should grasp favorable opportunities and quicken the pace of industrial structural adjustment; continue to open up to the outside world unswervingly, and improve investment environment ceaselessly; strive to maintain the continuous and rapid development of economy, and improve the living standard of people.

Investigating Maternal Mortality at Regina Pacis Hospital Mutengene and the Government Health Centre Mutengene, South West Region, Cameroon

Background: One target under sustainable Development Goal 3 is to reduce the global maternal mortality ratio to less than 70 per 100,000 births, with no country having a maternal mortality rate of more than twice the global average. So there is a need to identify ways to reduce maternal mortality which is a top priority in development of the management of pregnant women and invention of equipment in procedures (caesarian section) to provide a maternal health and increase life survival. Objective: This study aimed to investigate the prevalence and causes of maternal mortality at Regina Pacis Hospital and Government Health Center Mutengene. Method: This study was a retrospective study, where Data from 2007 to 2017 were collected from the hospital files using a checklist, descriptive and inferential statistics were used to analyse the data. Conclusion: From the finding, maternal mortality is at a pace of increase in the Regina Pacis Hospital and Government Health Centre Mutengene and these health facilitiesmay fail to achieve the target of SDG3 by the end of 2030. Since, the overall prevalence of maternal mortality at both study sites was 240 per 100,000 live births at Regina Pacis Hospital and Government Health Center Mutengene from 2007 to 2017, increase education of women of reproductive age on pregnancy care and training of hospital staff in obstetric management and health records documentation.

Assessment of Health-Related Quality of Life of Tuberculosis Patients in Fako Division, South-West Region of Cameroon

Background: Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the top 10 causes of death worldwide. Despite the global impact of TB and treatment received, a gap persists between treatment and quality of life of the patients especially in resource limited countries. This study therefore evaluated the health related quality of life of TB patients and the different factors influencing their quality of life at the post intensive phase of their treatment in the Fako division of the South-West Region of Cameroon. Methods: A hospital based cross sectional study was carried out in 4 tuberculosis treatment centers, namely two regional (Buea and Limbe) and two district (Tiko and Muyuka) hospitals in Fako Division between June and July 2017. One hundred and sixty-seven TB patients were enrolled in the study and relevant information from them was gathered using the SF-36 questionnaire. Various aspects such as their perception of the disease, their socio-demographics and socio-economics conditions were evaluated. Results: Of the 167 participants enrolled in the study, 95 (56.9%) were male and 72 (43.1%) were female. One hundred and thirty-three (79.6%) of the 167 participants were affected by pulmonary tuberculosis and 34 (20.4%) by extra-pulmonary tuberculosis. Fifty-five (32.9%) were HIV positive and 90 (53.9%) had been receiving treatment for 4 - 6 months, 73 (43.7%) for 1 - 3 months and 4 (2.4%) for 7 - 9 months. The lowest and highest scores were recorded on the role limitation due to emotional problems scale (30.54 ± 35.36), and on the social functioning scale (47.68 ± 16.33) respectively. There was a significant difference (p = 0.021), between pulmonary and extra pulmonary tuberculosis (49.15 ± 16.08 vs. 41.91 ± 16.25) on the social functioning. Financial difficulty restraining drug collection affected the general health perception (p = 0.003), vitality (p = 0.007), emotional well-being (p < 0.001) and social functioning (p = 0.05) of the patients. Low income affected the vitality (p = 0.039), emotional well-being (p = 0.015), role limitations due to physical (p = 0.046) and emotional (p = 0.003) problems of the patients. Equally, the HIV status affected their vitality (p < 0.001) and emotional well-being (p = 0.011). Conclusion: The quality of life of the TB patients in the study area was generally poor. Counselling of diagnosed TB patients and provision of financial assistance through a social package can improve the acceptance of the disease during their treatment period to avoid default and relapse.

Vegetation Coverage Changes in the West Qinling Region from 2000 to 2010:A Case Study of Longnan City

As the main content of terrestrial ecosystem study,vegetation coverage change has gained extensive attention in the process of global climate change and sustainable development recently.Based on MODIS NDVI data from June to October during 2000-2010,taking Longnan City as a case area,this paper develops the calculation method of vegetation coverage(VC) by using Pixel Dichotomy model and analyzes the spatial-temporal variation of vegetation coverage in the West Qinling region by using simple linear regression and standard deviation method.The results show that vegetation coverage remains stable and is significantly correlated with temperature and precipitation during the decade.The vegetation coverage of 90% of study area shows stability with small annual variation and also is consistent with the spatial distribution of forest land;the vegetation coverage in the remaining study areas shows a growing trend with significant variation and also is consistent with the spatial distribution of farmland and grassland,especially in Huicheng Basin,Xili Basin and adret slope of Bailongjiang River Valley,indicating that Project about the Conversion of Degraded Farmland into Forest has made a great contribution to vegetation coverage increase.This paper proves the effect of ecology construction in the West Qinling region since the late 20 th century.All the findings also provide references for local ecological environment construction and sustainable development.

Study on Development of the West of Shandong Province Based on Overall Regional Development Planning Pattern

The overall regional development planning pattern has been considered to be a new and effective pattern as for development of provincial economy.The article analyzed the current conditions of the west of Shandong Province and tried to find the generation mechanisms of current non-balanced economic development of Shandong Province.And then approaches to regional development were put forward according to the theory of regional development pattern as a whole.

Analysis on the Evolution of Regional Economic Disparity in the West Coast of the Strait

With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city and the countryside. The existence and evolution of this kind of economic disparity is concerned with social stability, sustainable development and the construction of harmonious society, which has gradually become the hotspot in social economic development. The West Coast of the Strait (WCS) located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east. The stability and development of this region has vital political and economic meaning in the social eco-nomic development of our country. It has important theoretical meaning and practical value to research the form, characteristics and evolution of regional economic disparity in the WCS. Based on insightful analysis on existing study results on the WCS, the paper defines the connotation and extension. By a series of abso-lute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object, the paper makes analysis on different scales including three regions, four regions, 20 cities and 152 counties, quantitatively evaluates the level, characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales. The main conclu-sions are as follows: the variation trend of the absolute disparity of the whole region is obvious and stable, which has presented an inflating trend; the comparative variation trend on a large scale has waved, The comparative disparity of the three regions in-creased annually from 1992 to around 2000, which had a decreas-ing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable, which showed an annual increase of four regions, 20 cities and 152 counties from 1992 to around 2003 and a decrease from around 2003 to 2005; there were some correlations between the regional disparity and scale. In other words, the smaller the scale was, the bigger the disparity was.

Study on the Delineation of Ecological Protection Red Line in Ecological Fragile Region of the West

Ecological protection red line is one of the main contents in system construction of ecological civilization in China, and also reflects the trend and the will of the national eco-environment protection system reform. In this paper, taking ecological fragile area of the west as the research object, and using literature analysis, comparative analysis and other methods, the characteristics in ecological fragile area of the west are compre-hensively elaborated, and the relationship between ecological vulnerability and ecological protection red line is clarified, and the delineation theory and methods of ecological protection red line are analyzed, such as ecological suitability analysis, regional ecological security pattern and DPSIR model. Finally, key issues of ecological protection red line delineation in ecological fragile zone of the west are proposed.

Mapping the Dyke Swarms of the Eglab-Yetti Region,Southwestern Algeria

The Eglab-Yetti region of southwestern Algeria is a main part of the Reguibat shield of the West African craton(WAC)which consists of Archean to Paleoprotzrozoic basement.The region hosts numerous

PECULIARITIES OF METALLOGENY OF SOUTH SIBERIA AND WEST MONGOLIA DIWA REGIONS

There are three diwa regions in South Siberia and West Mongolia. One of them is arranged in West Transbaikalia and was formed from Devonian till Carboniferous periods. Numerous deposits of tungsten , tin, molybdenum, REE, synnyrites, urtites are genetically linked with intrusive rocks. The next diwa region is arranged in North Mongolia and South Buryatia. This diwa region was formed in the Late Paleozoic time. The deposits of molybdenum, tungsten, boron, iron, copper, beryllium are genetically linked with magmatic rocks of this region. The third region was formed in Devonian in West Mongollia. The magmatic rocks of this region are represented by alkaline granitoids. Some deposits of REE and rare metals are linked with these rocks.

Assessment of Regional Climate Models over Côte D'Ivoire and Analysis of Future Projections over West Africa

The ability of six Regional Climate Models (RCMs) used in AMMA-ENSEMBLES project is assessed over six meteorological stations in C&#244te d’Ivoire. The ensemble mean of the models is also used for the prediction of climate change over West Africa. The study focused on two periods: the period 1995-2005, the present-day simulations, is used to evaluate the skills of the models over the country and the years 2010-2013, for assessment of the future climate change scenario used. The results show that the skills of the models vary from one station to another and from one season to another. None of the models considered, presents an excellent performance over the entire country and in all the seasons. Generally, the ensemble mean of all the models presents better results when compared with the observation. These results suggest that the choice of any model for study over the country may depend on the focus of interest: intensity or variability of the rain and also on area of interest. The projection for 2020-2040, future climate change over West Africa shows that the Sahel exhibits a tendency to be drier while wetter Guinean coast is observed.

Cumulative Coulomb Failure Stress Change in the Basin- range Region of West Beijing and Its Effect on Strong Earthquakes

Since 231 B. C.,a total of 15 M6.0 - 7.5 earthquakes have been recorded in the west Beijing basin-range tectonic region( 38.3°- 41.5° E,112°- 116.2° N),a region mainly under the action of tensional normal faulting. In this paper,we calculate the Coulomb stress change of each earthquake and the cumulative Coulomb stress change,and on this basis we analyze the stress triggering of strong earthquakes. The research shows that there are 10 of 14 earthquakes that occurred in the trigger zones,in which the Coulomb stress change is positive,and the trigger rate is 71%. The positive areas of cumulative Coulomb stress change caused by these 15 earthquakes are: middle of northern Liulengshan fault,Northern Huaizhuo basin fault,Xinbaoan-Shacheng fault,Sangganhe fault and Southern Yuxian basin fault. This necessarily increases the seismic risk of these faults and can be used as a reference for future seismic risk analysis in this area.