NUMERICAL SIMULATION OF 1998 RED TIDE OF THE BOHAI SEA

1 INTRODUCTION The Bohai Sea, located in East China, consists of five parts: Bohai Bay, Liaodong Bay, Laizhou Bay, Central Bohai and the Bohai Strait, as shown in Fig.1. The average water depth of the semi-enclosed sea is only 17 m. The maximum water depth is 70 m, measured in the Bohai Strait. Surrounding the Bohai Sea are 17 industrial cities, including Beiijing, Tangshan, Tianjin, Dalian, Huanghua and Dongying. More than 50 rivers, including the Haihe, Liaohe, Yellow, and …     

Regional carrying capacity: case studies of Bohai Rim area

Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim’s sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.     

环渤海地区文化产业结构趋同合意性研究

运用产业结构相似系数,对环渤海地区五省份的文化产业结构进行静态和动态分析,明确环渤海地区文化产业结构是否趋同以及趋同的程度,在此基础上,进一步利用偏离-份额法对环渤海地区的产业结构趋同是否合意进行判定。结果表明:环渤海地区五省份存在不同程度的文化产业结构趋同,以全国为基准,河北的产业结构相似系数较低,北京最高,表明北京与全国的文化产业结构最为相似。从文化产业结构趋同合意性来看,山东的经济增长份额、结构偏离份额、竞争偏离份额均表现为正值,因此,山东的文化产业结构为合意性趋同,而北京、天津、辽宁、河北的文化产业结构为非合意性趋同。     

1985年来环渤海地区港口体系位序—规模分布及作用机制

运用位序—规模法则与核密度方法,以近30年来各港口货物吞吐量及集装箱吞吐量为主要指标,刻画环渤海地区港口体系的规模分布特征,分析其作用机制。结果表明：① 总体看,环渤海地区港口体系具有一定位序—规模分布特征,但不同阶段、不同规模的港口在位序分布上出现明显分化,港口区域化特征愈发明显。② 港口货物吞吐量位序—规模分布的无标度区数量先增后减,最终由单分形变为双分形结构。区域港口体系经历了高位序平衡发展、中小港口突破、大中小港口差异化发展、枢纽港竞合下的港口融合四个阶段。港口集装箱吞吐量位序—规模分布的变化轨迹呈现外接式分割发展、枢纽港形成及新兴港口融入、支线港大型化和集装箱网络整合四个阶段。两者在发展节点上基本吻合;港口集中化与分散化交织进行,货物总吞吐量的分散化早于集装箱运输,分散趋势较为明显。③ 环渤海地区港口体系位序—规模演化的作用机制突出表现为自然经济地理约束下的大港口主导作用明显、区域化和竞争压力倒逼港口合作并推动港口实现自组织协调、能源输出特征及转型推动新兴港口快速成长三方面。     

Sequence Stratigraphic Delineation and Correlation of the Dongying Formation in the Nearshore and Adjacent Sea Areas, Bohai Bay Basin

Based on the analysis of well logs, seismic data, core studies, the Dongying (东营) into three third-order sequences from base to top: namely, sequences SQ1, SQ2 and SQ3. The three sequences have different wireline (SP) log responses, showing triple-section characteristics with SQ1 being characterized by primarily flat baseline with intercalation of relatively low spontaneous potential, SQ2 generally exhibiting weak or moderate amplitude spontaneous potential with finger-shaped peaks, and SQ3 having relatively high spontaneous potential with funnel-shaped log curves. On the basis of the triple-section characteristics, the stratigraphic sequences can be correlated consistently throughout the entire study area. A stratigraphic and sedimentary model for sequences SQ1 to SQ3 of the Dongying Formation in the study area has been proposed. The accommodation space change in the two sides of the asymmetrical basin was examined and the asymmetrical basin has the feature of the asymmetrical accommodation space change. The asymmetrical physiography is a vital factor to influence the accommodation changes in additional to the lake level change, tectonism and sediment supply. This may have important implications to similar basins in other parts of China or elsewhere.     

1：50000数字地理底图在地质环境调查中的应用

数字地理底图为地质部门编制各种专题图提供基本地理要素。以环渤海曹妃甸滨海地区为例,以1：50000地形图为基本数据源,依据标准使用GIS软件完成了1：50000数字地理底图的制作,并对如何更好地发挥1：50 000数字地理底图在地质环境调查中的重要作用提出建议。     

Seismic profiles across the middle Tan-Lu fault zone in Laizhou Bay, Bohai Sea, eastern China

The stratigraphic architecture, structure and Cenozoic tectonic evolution of the Tan-Lu fault zone in Laizhou Bay, eastern China, are analyzed based on interpretations of 31 new 2D seismic lines across Laizhou Bay. Cenozoic strata in the study area are divided into two layers separated by a prominent and widespread unconformity. The upper sedimentary layer is made up of Neogene and Quaternary fluvial and marine sediments, while the lower layer consists of Paleogene lacustrine and fluvial facies. In terms of tectonics, the sediments beneath the unconformity can be divided into four main structural units: the west depression, central uplift, east depression and Ludong uplift. The two branches of the middle Tan-Lu fault zone differ in their geometry and offset: the east branch fault is a steeply dipping S-shaped strike-slip fault that cuts acoustic basement at depths greater than 8 km, whereas the west branch fault is a relatively shallow normal fault. The Tan-Lu fault zone is the key fault in the study area, having controlled its Cenozoic evolution. Based on balanced cross-sections constructed along transverse seismic line 99.8 and longitudinal seismic line 699.0, the Cenozoic evolution of the middle Tan-Lu fault zone is divided into three stages: Paleocene–Eocene transtension, Oligocene–Early Miocene transpression and Middle Miocene to present-day stable subsidence. The reasons for the contrasting tectonic features of the two branch faults and the timing of the change from transtension to transpression are discussed.     

渤海湾盆地车镇凹陷古近系构造样式对沉积及储集层的影响*

近年来,构造对沉积的控制作用研究成为当前国际地质和油气勘探研究中的一个热点,但构造对储集层质量影响的研究相对较缺乏。在对车镇凹陷构造、沉积、储集层研究的基础上,讨论了不同构造样式中沉积充填和储集层发育特征。构造样式对沉积充填类型及特征具有重要影响,其中板式构造样式区仅发育近岸水下扇及少量滑塌浊积扇;铲式构造样式区除在边界断裂根部附近发育近岸水下扇外,其前端湖底扇常较发育;断阶式和坡坪式构造样式区受次级断裂控制,陆上与水下沉积常常共生,沉积类型多样,从冲积扇、扇三角洲到近岸水下扇、湖底扇均可发育。构造样式通过影响砂砾岩体的垂向叠置方式、规模和沉积类型及砂体结构,最终影响了其储集层质量。综合研究认为,断阶式和坡坪式构造样式区沉积类型丰富,为有利储集层最发育区;铲式构造样式区湖底扇发育,砂砾岩单层薄,为次级有利区;而板式构造样式区砂砾岩展布窄、单层厚度大,储集层质量最差。该认识为中低勘探程度的含油气断陷盆地中优质储集层发育带的预测提供了思路。     

华北地区构造演化对渤海湾油气形成和分布的控制

华北地区的构造演化大致经历５个阶段,即陆核及基底形成阶段;中、新元古代裂陷槽发育阶段;古生代稳定地台发育阶段及其南北缘的造山作用;中生代中后期欧亚构造域与滨太平洋构造域过渡期;新生代滨太平洋构造域大发展时期。区域构造演化对渤海湾乃至华北地区油气的形成和分布具明显控制作用,主要表现在：中生代隆坳相间格局决定了古生代油气勘探的方向,是勘探新生古储潜山油气藏的主要地区;渤海湾盆地火山岩油气藏勘探也是今后