Measuring West-Africa Ports Efficiency Using Data Envelopment Analysis

The present study measured the relative efficiency of five major commercial ports in West Africa, using three different Data Envelopment Analysis (DEA) methods, the CCR, BCC, and Windows I-C methods over the years 2005-2016. Seven input variables and one output variable were used in the model analysis. The CCR and BCC methods were used to evaluate the technical and scale efficiency while the Windows I-C method provided a comprehensive ranking of the studied ports. The results showed that the scale efficiency score of 89.53% indicated that on average the production scale of the ports had deviated from the most productive scale size (MPSS) by 10.47%. These results revealed that the source of the overall inefficiency is due to scale rather than pure technical inefficiency. Hence, in order to improve the overall efficiency, the two scaled inefficient ports of Abidjan and Cotonou should adjust their scale of operations. Then, further investigations were conducted to detect correlations between various variables used in this study. The research found that the absence of any correlation for non-significant variables and negative correlation for the significant variables throughout time resulted from the fact that these variables were not fully utilized. Meaning that they were not efficiently used to boost the container throughput on a scale basis, the research also found that a pandemic or insecurity could easily impact seaports activities with the case of the Ebola outbreak which strucked the West African region from the year 2013 to 2016, or the terrorism threats which prevailed in the region around the year 2012. Thus, for ports to stand out in the present fiercely competitive environment, ports authorities ought to analyze their operational scale to identify whether or not the production size is fitting before further port capacity expansion.

西非北部被动陆缘盆地油气地质特征与勘探方向

西非北部盆地勘探程度较低,但资源潜力巨大。基于板块构造理论,通过结合地震与地质方法的综合研究,分析了西非北部主要地质时期的原型盆地,对比了各盆地的结构特征及其沉积充填差异性,解剖已发现油气藏,建立成藏模式,指出下一步勘探方向。研究发现:西非北部被动陆缘盆地群经历了前寒武纪—二叠纪前裂陷、三叠纪—早侏罗世裂陷和中侏罗世至今的陆缘3个演化阶段,形成了断陷型、断坳型和坳陷型3个被动陆缘盆地亚类。断陷型盆地形成单源-构造型成藏模式,勘探目标以裂谷层系的构造成藏组合为主;断坳型盆地可形成双源-双组合型成藏模式,大陆架上的缓坡带以裂谷层系构造圈闭为主,在台地边缘应寻找礁体和内幕岩溶,陡坡带上部的主要勘探目标应为规模较大的滑动-滑塌形成的斜坡扇,下部应关注成熟烃源岩层系内扇体所形成的上白垩统和下白垩统砂岩构造-岩性圈闭;坳陷型盆地以坳陷层系烃源岩为主,主要勘探对象为陡坡下部的浊积砂岩及台地缓坡三角洲砂体,台地边缘礁滩体、台地碳酸盐岩风化壳岩溶和断裂带岩溶也是值得重视的勘探方向。研究可为勘探程度低、资料获取难的被动陆缘深水油气勘探选区评价提供借鉴。

基于增强回归树的西非北部沿海底拖网主要商业头足类CPUE与主要环境因子的关系

【目的】研究西非北部沿海不同环境因子对章鱼、墨鱼和鱿鱼等主要商业头足类单位捕捞努力量(CPUE)影响的规律,为合理规划商业性捕捞生产和科学渔业管理等提供参考。【方法】基于2019-2021年西非北部沿海底拖网渔业数据,使用增强回归树模型(BRT)分析主要商业头足类对于海表面温度(SST)、叶绿素质量浓度、海表面盐度、海表面高度异常,溶解氧浓度、降水量、经度、纬度、海底深度、离岸距离和时间等环境因子的响应规律。【结果与结论】BRT模型在渔业研究中尤其在数据处理方面较传统模型优势明显。本研究以相对重要性值划分11个环境因子对于商业头足类(章鱼、墨鱼和鱿鱼)CPUE影响的强弱:强重要性(10%以上)、一般重要性(5%~10%)和弱重要性(5%以下)。BRT拟合结果表明,SST、纬度、降水量和离岸距离对章鱼CPUE影响有强重要性,纬度、SST、叶绿素质量浓度对墨鱼CPUE影响有强重要性,而降水量、溶解氧浓度、SST对于鱿鱼CPUE影响有强重要性。纬度对章鱼和墨鱼的CPUE影响有强重要性,较高的CPUE分别出现在24°N以南(章鱼)和23°N―27°N之间(墨鱼);离岸距离对章鱼和鱿鱼CPUE影响均在一般重要性以上,离岸30~70 km范围内CPUE较高;3种头足类中,鱿鱼CPUE受时间影响最大,较高CPUE出现在1月和7月。环境因子中,SST对3种头足类影响均有强重要性,相对重要性均在20%以上,其中对于章鱼和墨鱼影响效应相反,章鱼趋暖而墨鱼趋寒;溶解氧浓度与鱿鱼CPUE呈正相关;叶绿素质量浓度对墨鱼CPUE影响有强重要性,叶绿素质量浓度较低时CPUE较平稳,但当质量浓度超过4 mg·m^(-3)时CPUE却逐渐下降。降水量对于3种头足类CPUE影响均在一般重要性以上,随降水量增加,鱿鱼CPUE有所上升,而章鱼和墨鱼CPUE先升高后降低。

Isotope Tracking of Surface Water Groundwater Interaction in the Beninese Part of the Iullemeden Aquifer System

The Kandi basin is located in northeast Benin (West Africa). This study is focused on the estimation of water fluxes exchanged between the river Niger (and its tributaries) and the transboundary Iullemeden Aquifer System. In that framework, an innovative approach based on the application of the Bayesian Mixing Model (MixSIAR) analysis on water isotopes (oxygen-18, deuterium and tritium) was performed. Moreover, to assess the relevance of the model outputs, Pearson’s correlation and Principal Component Analysis (PCA) have been done. A complex relationship between surface water and groundwater has been found. Sixty percent (60%) of groundwater samples are made of more than 70% river water and rainwater;while 31.25% of surface water samples are made of about 84% groundwater. To safeguard sustainable water resources for the well-being of the local communities, surface water and groundwater must be managed as a unique component in the Kandi basin.

Epidemiology and Prognosis of Hepatocellular Carcinoma (HCC) in the Internal Medicine Department of the Bouake University Hospital (Côte d’Ivoire)

Background and Objective: Hepatocellular carcinoma (HCC) is a public health problem due to its high incidence and high mortality rate. The epidemiology and prognosis of this disease is poorly documented in Bouake. The aim of the study was to describe the epidemiological aspects and identify the predictors of death in patients hospitalized for HCC in the Internal Medicine Department of the Bouake University Hospital in order to improve patient management. Material and Methods: We conducted a cross-sectional study from 1 January 2020 to 31 December 2022 in the Internal Medicine Department of Bouake University Hospital, involving 160 patients. Results: The prevalence of HCC was 3.6%, the mean age was 48.86 ± 14.5 years with extremes of 14 and 90 years and the sex ratio was 2.90. Viral hepatitis B was observed in 81% of patients, with HBs Ag positivity in 71.2%. The performance status of WHO was ≥ 2 in 93.2% of cases. HCC was discovered at advanced stage respectively in 51% for BCLC C and 47.8% for BCLC D stage. The nodules were multiple (89.3%), and superior to 3 cm. The hospital mortality was 20% and BCLC D stage of HCC was significantly associated with death (p = 0.04) in the univariate analysis. The BCLC D stage of HCC was significantly associated with death. Length of stay inferior to 5 days (OR = 0.77;CI 95: 0.61 - 0.96) and hepatic encephalopathy (OR = 1.39;CI 95: 1.10 - 1.77), were the two independent predictors of mortality. Conclusion: HCC mainly affected young men infected with chronic viral hepatitis B. Short length of stay and hepatic encephalopathy were independent predictors of mortality.

Assessment of the Physical Capabilities of Heart Failure Patients before and after Cardiovascular Rehabilitation: A Study of 125 Patients from West Africa, Dakar, Senegal

Background: Cardiac rehabilitation represents a critical therapeutic strategy for patients suffering from chronic heart failure. The physical capacity of patients with heart failure, assessed using the exercise test and the 6-minute walk test, is the measure of the patient’s overall functional ability to perform physical activities and tolerate exercise loads. The objective of this study was to assess the impact of cardiac rehabilitation on patients’ physical capabilities and to conduct a thorough comparison of data obtained via exercise testing and the 6-minute walk test before and after the rehabilitation programme. Methods: This was a descriptive and analytical cross-sectional study, conducted from 1 February 2021 to 31 June 2022. Included were heart failure patients who had participated in an outpatient cardiovascular rehabilitation programme. The collected data included anamnestic, clinical, paraclinical data, and the 6-minute walk test. Informed consent was obtained. Data analysis, word processing, and charting were performed using Microsoft Word 2016, Excel 2013, and Sphinx version 5.1.0.2. Data analysis was performed using SPSS (Statistical Package for Social Sciences) version 24.0. Any difference less than 0.05 was considered statistically significant. Results: In a Senegalese study, heart failure patients undergoing rehabilitation in a cardiac unit represented 45.59% of all cases, with a prevalence rate of 3.21%. The average participant was 57.97 years old, with those aged 61 to 70 forming the largest group (35.5%). The study noted a male predominance (sex ratio of 2.1) and identified dyslipidaemia (80.6%) and sedentarism (71%), as prevalent cardiovascular risk factors. All participants initially suffered from NYHA stage 2 or 3 dyspnoea, yet 80.65% showed no symptoms following rehabilitation. Significant improvements were recorded in resting heart rate (from 79 to 67 bpm), and the 6-minute walk test distance (from 328 m to 470 m). Enhanced exercise tolerance and walking test outcomes were particularly notable in patients with LVEF ≥ 50%, women, non-obese individuals, those initially walking less than 300 m, achieving more than 3 METs, and non-smokers. Conclusion: The findings underscore the effectiveness of cardiovascular rehabilitation in improving symptoms, physical capability, and overall quality of life for heart failure patients in Senegal.

Magma Mixing Genesis of the Mafic Enclaves and Related Granitoids in the Kan Granite-Gneiss Complex of Central Côte d’Ivoire: Evidence from Geology, Petrology and Geochemistry

The mafic enclaves from Paleoproterozoic domain are considered to be the results of large-scale crust-mantle interaction and magma mixing. In this paper, petrography, mineralogy and geochemistry were jointly used to determine the origin of the mafic enclaves and their relationship with the host granitoids of the Kan granite-gneiss complex. This study also provides new information on crust-mantle interactions. The mafic enclaves of the Kan vary in shape and size and have intermediate chemical compositions. The diagrams used show a number of similarities in the major elements (and often in the trace elements) between the mafic enclaves and the host granitoids. Geochemical show that the Kan rock are metaluminous, enriched in silica, medium to high-K calc-alkaline I-type granite. The similarities reflect a mixing of basic and acid magma. Mafic enclaves have a typical magmatic structure, which is characterized by magma mixing. The genesis of these rocks is associated with the context of subduction. They result from the mixing of a mafic magma originating from the mantle and linked to subduction, and a granitic magma (type I granite) that arises from the partial melting of the crust.

西非砾质红土粒料掺砂改良及水泥稳定处置研究

西非砾质红土粒料存在颗粒组成不良、液限与塑性指数偏高的现象,限制了该典型地材在道路结构中的应用。该文通过对多种红土粒料以及掺砂改良前后的颗粒组成、界限含水率、CBR试验进行研究,结果表明:掺砂改良可以改善砾质红土粒料级配,提高密实度,降低塑性指数,改良后的砾质红土可满足道路底基层、垫层及基层的使用要求。水泥稳定处置可提高西非红土粒料的力学特性。试验结果表明:水泥剂量与砂掺量对无侧限抗压强度影响明显,砂掺量存在最佳用量范围,2.5%水泥剂量的PK58水泥稳定掺砂红土粒料和3.5%水泥剂量的PK6水泥稳定掺砂红土粒料可满足西非地区倒装结构中垫层材料使用要求。对西非地材的属地化设计与优化改良,可以扩大典型地材的使用范围、提升使用层次,为中国在西非地区的道路工程项目建设提供借鉴。

Socioenvironmental Drivers of Farmers’ Perceptions of Climate Change Risk in Agroforestry Parklands of West Atacora in Benin (West Africa)

Throughout the world, climate change is threatening the human population. In West Africa, smallholder farmers in indigenous agricultural societies typically hold considerable knowledge. Therefore, this study was conducted in West Atacora of Benin Republic to assess the drivers of farmers’ perceptions of climate change risk. We used a random sampling technique to select 360 households’ heads who were interviewed regarding different climate change risks perception. Binomial logistic regression was used to assess the drivers of farmers’ perceptions of climate change risks. The results showed that the farmers in drier areas had a higher perception of the global risk of climate change than those in humid areas. The same trend was observed for the seven different individual’s climate change risk investigated. The study identified also membership of farm organizations as main sociodemographic characteristic that explains farmers’ perception of climate change risk perception. These findings are helpful tools to sensitize the local people on climate change risk and cope with the risk in agricultural lands.

西非法语国家民族语言发展的困境与前景

西非法语国家以法语为官方语言,并将之作为教育体系各阶段的教学语言。该地区民族语言众多,发展状况各异,因而形成了复杂的语言生态。在现行西非法语国家的语言政策当中,民族语言遭遇的主要问题是:地位规划较为模糊,本体规划薄弱,教育体系中的融入也面临着各种困难。然而,民族语言在西非法语国家语言生态中仍然发挥着重要的交际功能,是国家文化遗产的重要组成,影响着国家身份认同和民族团结的构建。未来,西非法语国家的民族语言可依托国家、区域和国际层面的合力,寻求生存和发展的更大空间。

加纳特马新港防波堤断面优化试验研究

为满足加纳特马新集装箱码头防波堤工程设计的需要,进行了波浪断面物理模型试验,对防波堤护面稳定性及堤后波高开展试验研究。结果表明:原设计方案防波堤不能满足稳定要求,对断面进行了优化试验,结合抬高堤顶块石高程和减小堤后斜坡坡度2种方式可有效增加堤后斜坡护面块石稳定性。波浪断面试验中将斜向入射波浪概化成正向入射波浪使得实验结果偏安全,没有条件开展波浪整体物理模型的时候,可以采用对波高进行折减的方法考虑斜向入射的影响。

加纳特马港防波堤稳定性局部物理模型试验研究

非洲西海岸几内亚湾涌浪周期长、风暴期间大浪持续时间长,加纳特马港新集装箱码头防波堤还受到斜向浪作用,为研究防波堤转弯段的护面稳定性,建立了港池局部整体物理模型。试验结果表明,防波堤各部位满足稳定要求,但转弯段和堤根段局部堤顶护面块石的失稳数较大。分析了波浪入射角对防波堤各部位稳定的影响,堤顶和堤后块石主要受越浪的作用,波浪和堤轴线夹角较大时,波浪入射角些许变化对堤顶及堤后块石稳定影响不明显;波浪和堤轴线夹角较小时,波浪入射角增大导致越浪量变大使堤顶及背浪面块石失稳数增大。

尼日利亚中生代碱性花岗岩和黑云母花岗岩成因及其对锡多金属找矿的指示

尼日利亚中生代环状杂岩中产出丰富的含锡(铌钽)等多金属的花岗岩,其中与成矿相关且占主体的2种岩石类型是碱性花岗岩和黑云母花岗岩,前者具有含碱性暗色矿物过碱质特征,后者具有含黑云母过铝质特征。前人对2种共生的岩石对锡(铌钽)成矿作用可能的制约机制还未深入探讨,综合分析前人研究资料,为理解非造山A型花岗岩锡(铌钽)成矿作用提供新视角,进一步明确找矿方向。2种岩石绝大多数在侏罗纪侵位,但在同一杂岩体中,碱性花岗岩锆石结晶普遍稍早于黑云母花岗岩,且前者分异程度稍弱于后者。碱性花岗岩是起源于富集地幔岩浆在极端分离结晶作用下的产物,但此过程中有部分地壳物质的混染。过铝质黑云母花岗岩并非与造山型过铝质花岗岩一样来自地壳物质的熔融,它更可能是来自于碱性花岗岩同一母岩浆演化的另一个混染了更多地壳物质的晚期分支。与俯冲背景的成锡花岗岩一样,尼日利亚锡多金属富集主要与弱过铝质黑云母花岗岩有关,受岩浆后期出溶流体的显著影响。碱性花岗岩对锡(铌钽)元素的富集程度,大致代表了未受出溶流体影响时共生黑云母花岗岩的锡(铌钽)含量。成矿物质来源为泛非基底围岩,元素的富集成矿主要被分离结晶和流体出溶行为控制。尼日利亚不成矿环状杂岩体中,黑云母花岗岩和碱性花岗岩的锡(铌钽)含量都偏低,两者的Sn含量范围为4×10^(-6)~13×10^(-6);而对于成矿杂岩体,两者锡(铌钽)含量基本高于不成矿杂岩体,但其中与成矿密切相关的黑云母花岗岩锡(铌钽)含量反而较碱性花岗岩偏低,其中碱性花岗岩Sn含量范围为21×10^(-6)~205×10^(-6),黑云母花岗岩Sn含量范围为10×10^(-6)~62×10^(-6),表明熔体中成矿元素含量高低及后期流体出溶是决定能否成矿的关键。因此,高锡(铌钽)含量杂岩体中具有较低Sn含量的黑云母花岗岩是寻找锡多金属矿的第一选择。

西非科特迪瓦盆地深水底形样式及成因分析

通过三维地震资料海底平面成像和浅层地震剖面解释、分析,识别和描述了西非科特迪瓦盆地深水底形类型。研究区发育下切水道、侵蚀冲坑、周期阶坎、小型沉积物波、大型沉积物波多种深水底形。下切水道表现为直线型,地形坡度从上斜坡5°过渡到下斜坡1.9°,水道历经多次合并,合并后水道内部起伏地貌指示侵蚀—沉积交互作用;识别出孤立状、串珠状和猫爪状三种类型侵蚀冲坑;在斜坡限制性水道内部地形坡度1.9°~3.1°之间识别出8个不同波长和波高的“周期阶坎”底形,周期阶坎具有剖面上向上游方向迁移、平面上呈新月形态的特征,从上游到下游波长有逐渐变短的趋势。小型沉积物波发育于水道内和水道外两种环境,其中限定性环境小型沉积物波发育在周期阶坎上游方向,非限定环境小型沉积物波发育地形坡度为1°左右,具有加积或轻微向下迁移的内部反射结构。大型沉积物波发育在非限定环境中,显示为长波长、低幅度浅层构造特征,分析认为早期滑塌地貌对晚期大型沉积物波的形成具有重要的控制作用。在现象描述基础上,对不同底形的成因、形成过程、控制因素和其发育的深水动力学背景与环境展开探讨,加深了对西非赤道段科特迪瓦盆地深水底形成因的认识,可对未来深水区油气勘探砂体分布预测提供借鉴和参考。

陆坡逆冲-变换构造对重力流水道的控制作用——以西非陆坡某区中新统深水沉积体系为例

重力流水道是深水油气勘探的重要目标之一,近年来的勘探实践揭示了陆坡逆冲构造区重力流水道复杂的分布特征。以西非陆坡某研究区为例,综合应用地质和地震资料,阐明逆冲-变换构造微地貌的类型、成因和对重力流水道的控制作用。中新世由重力滑动作用引发的逆冲断层主导了研究区地貌格局。东、西2套逆冲断裂体系沿下伏厚层超压泥岩中不同深度的滑脱面发育,导致位移缩短量不同,这是二者构造样式与活动强度差异的主因。不同逆冲断裂体系间的位移量差异及沿单一逆冲断层走向的位移量变化使研究区内发育多种变换构造。从成因的角度归纳出在逆冲-变换构造的综合作用下发育5种微地貌样式:三角形断背斜、捩断层-底辟背斜、逆断层连接沟谷、捩断层斜坡和走向凹槽。同期重力流水道在逆冲-变换构造微地貌的影响下表现出遇障碍转向、穿越断层相关构造和两侧受限制等3种分布样式:三角形断背斜和捩断层-底辟背斜使顺陆坡方向的重力流水道转向;逆断层连接沟谷和捩断层斜坡边缘使重力流水道容易从此处穿越;走向凹槽将重力流水道限制于其中。该研究为针对重力流水道储层的地震解释提供了一种新的思路。

激发极化法在西非加纳某锰矿勘查中的应用

针对热带雨林地区植被覆盖广、地质露头少,传统地质找矿手段难以发挥作用的问题,本文提出利用地球物理方法探查隐伏锰矿体的思路。在分析在产矿山地质特点与地球物理特征基础上,首次将激发极化法应用到加纳西部省某锰矿增储勘查中,通过圈定激电中梯剖面低阻高极化异常确定矿体平面位置,再利用激电测深中相对高阻高极化异常判断碳酸锰矿体位置及展布形态。分析显示推断矿体位置锰含量高达40.99%,证明了方法的有效性,对同类型锰矿勘查工作具有指导意义。

西非法语地区水泥稳定黏土质砂工程应用研究

为了研究西非法语地区广泛分布的黏土质砂材料工程应用价值,首先对西非法语地区的典型黏土质砂进行差异性取样,测试其基本物性指标来确定土样的应用价值和取样代表性。然后,通过先后掺入无塑性砂和CEM II/B-LL42.5型水泥来制作水泥稳定黏土质砂。最后,在中欧试验和标准的基础上,进行了西非法语地区地源型粘质砂的无侧限抗压强度试验,提出了粘质砂在西非国家的应用方案。结果表明:西非法语地区土质原材料不同区域之间存在显著性差异,其中CBR试验结果变异系数高达0.343 1,本文针对性的应用探究是有意义的;结合现场施工工艺和实验室测试结果,西非法语地区水泥稳定黏土质砂中无塑性砂和水泥满足使用需求的普适性阈值分别为13.1%~15.1%和>2.5%;针对西非法语地区当地材料的力学测试方面,中国标准整体上来说要严于法国标准,可以考虑在当地应用中国规范标准进行路基施工控制。

非洲西部地区典型硬质沥青技术性能

随着中国在非洲西部国家援建项目逐渐增多,研究非洲西部硬质沥青在内的典型材料的技术性能,对于中国技术标准走出去和在当地属地化应用具有重要意义。研究了非洲西部地区常用的3种典型硬质沥青:Termcotank、DHS、ERES,对其常规物理性能、流变性能、高低温等级及疲劳性能进行了测试分析。研究结果表明,Termcotank沥青高温性能最好,低温性能略差,适合用于对高温性能要求较为严格的地区;DHS和ERES沥青高温性能和低温性能较好,适合针对高低温均有要求的路面;3种硬质沥青除了Termcotank的低温延度,其他指标均能满足中国规范要求。按照美国战略公路研究计划(strategic highway research program,SHRP),3种沥青的性能分级(performance grade,PG)分别为PG76-10、PG70-16、PG70-16。根据PG分级确定了两种沥青适合的气候分区,同时根据统计分析给出了评价硬质沥青低温性能的建议性能指标。

基于重力P-中值的非洲西海岸集装箱枢纽港选择

在“一带一路”的背景下,中资企业在非洲港口的投资和运营业务不断拓展。为了选择非洲西海岸更便利货主的集装箱枢纽港,完善以枢纽港为核心的现代化港口群服务体系建设,基于重力P-中值模型,从腹地货主的视角,以枢纽港-腹地的总运输阻抗最小为优化目标,综合选择竞争力较强且更靠近腹地经济发展重心的港口组成枢纽港口群,讨论了不同数量的枢纽港设置条件下的非洲西海岸枢纽港选择方案。结果表明:当前格局下,该区域集装箱枢纽港的最优选择方案为丹吉尔港、洛美港和德班港构成第一层级的核心枢纽港,而达喀尔港、阿比让港、杜阿拉港、罗安达港和开普敦港构成第二层级的区域型枢纽港。按照不同的港口功能定位进一步提出了针对性的发展建议。

西非几内亚湾油气差异分布主控因素分析

西非几内亚湾蕴藏了极为丰富的油气资源,是国际油气勘探开发的热点地区。以西非几内亚湾尼日尔三角洲盆地、下刚果盆地、宽扎盆地和加蓬海岸盆地为例,在对其油气成藏条件进行研究的基础上,总结各盆地油气分布规律,并分析油气成藏主控因素。研究结果表明,西非几内亚湾4个主要含油气盆地油气成藏条件较为优越,发育盐下、盐间和盐上多套生储盖组合,其中尼日尔三角洲盆地和下刚果盆地以发育盐上生储盖组合为主,宽扎盆地以发育盐下生储盖组合为主,加蓬海岸盆地北加蓬次盆以发育盐上生储盖组合为主,南加蓬次盆以主要发育盐下生储盖组合为主。各盆地油气分布特征差异较大,尼日尔三角洲盆地油气分布具有纵向上“集中”、平面上“广泛”的特点,下刚果盆地具有“陆下海上”的特点,宽扎盆地具有“陆上海下”的特点,加蓬海岸盆地具有“北上南下”的特点。烃源岩是4个盆地油气成藏最主要、最直接的控制因素,其次是沉积构造演化作用和盐岩。