Comparative Analysis of Mitochondrial Control Region Sequence from Three Flatfish Species （Pleuronectidae）

The 5‘-end of the mitochondrial control region sequences of three flatfishes (Pleuronectiformes: Pleuronectidae) were amplified and sequenced. These sequences were compared with those of other three Pleuronectids species retrieved from GenBank. A phylogenetic tree was constructed based on the partial control region sequences. The results of phylogenetic analysis are consistent with those of conventional systematics. Compared to previous studies, the structure of the 5‘-end of mitochondrial control region was analyzed. The terminal associated sequence motif and its complementary motif were identified at the 5‘-end of the sequences. A conserved sequence block, named as CM5‘ d, was identified in the 5‘-end of control region sequences in all Pleuronectids. Another central conserved sequence block, named as CSB-F, was detected in the central conserved blocks.     

The new hominid skeleton from Sterkfontein,South Africa: age and preliminary assessment

A new hominid skeleton from Sterkfontein Member 2 attaches to foot bones recovered from loose blocks during the 1980s and first described in 1995. Several flowstone horizons are present above and below the skeleton and have given clear palaeomagnetic signatures. Five changes in magnetic polarity have been identified; when constrained by the available biostratigraphy, this sequence can be placed confidently between 3.22 and 3.58 Ma. Interpolation of sedimentation rates over the small intervals between reversals allows this range to be reduced to 3.30–3.33 Ma. The skeleton is thus the oldest yet discovered and is considered to belong to a species of Australopithecus other than africanus. Copyright © 1999 John Wiley & Sons, Ltd.     

Detrital zircon age spectra of middle and upper Eocene outcrop belts,U.S. Gulf Coast region

Recently reported detrital zircon (DZ) data help to associate the Paleogene strata of the Gulf of Mexico region to various provenance areas. By far, recent work has emphasised upper Paleocene‐lower Eocene and upper Oligocene strata that were deposited during the two episodes of the highest sediment supply in the Paleogene. The data reveal a dynamic drainage history, including (1) initial routing of western Cordilleran drainages towards the Gulf of Mexico in the Paleocene, (2) an eastward shift of the western continental divide, from the Jura‐Cretaceous cordilleran arc to the eastern edge of the Laramide province after the Paleocene and (3) a southward shift, along the eastern Laramide province, of the headwaters of river systems draining to the Mississippi and Houston embayments at some time between the early Eocene and Oligocene. However, DZ characterisation of most (~20 Myr) of the middle Eocene‐lower Oligocene section remains limited. We present 60 DZ age spectra, most of which are from the middle or upper Eocene outcrop belts, with 50–200‐km spacing. We define six to eight distinct groups of DZ age spectra for middle and upper Eocene strata. Data from this and other studies resolve at least six substantial temporal changes in age spectra at various positions along the continental margin. The evolving age spectra constrain the middle and upper Eocene drainage patterns of large parts of interior North America. The most well‐resolved aspects of these drainage patterns include (1) persistent rivers that flowed from erosional landscapes across the Paleozoic Appalachian orogen either into the low‐lying Mississippi embayment or directly into the eastern Gulf; (2) at least during marine regressions, a trunk channel that likely flowed southward along the axial part of Mississippi Embayment and integrated tributaries from the east and west; and (3) rivers that flowed to the Houston embayment in the middle Eocene that likely originated in the Laramide province in central Colorado and southern Wyoming, as Precambrian basement highs in those source areas were being unroofed.     

阿尔及利亚韦德迈阿次盆地438B区块泥盆纪层序-岩相古地理特征

泥盆系是富含油气的阿尔及利亚韦德迈阿次盆地西北部438B区块重要的含油层位之一,可划分出2个三级层序,仅下部的SQ1层序保存较完整;泥盆系属于快速海侵缓慢海退的沉积旋回,由海侵、早期高位和晚期高位3个体系域叠加组成。在SQ1层序中相当体系域级别的地层单元在区域上具有良好的等时性,仅在研究区东、南部外侧构造隆起区明显变薄或局部缺失海侵体系域地层。各体系域中,早期高位体系域的障壁砂坝在纵向上具有更好的可比性,反映该体系域障壁砂坝砂体的发育层位和沉积厚度更稳定,砂体连通性和储集性更好,但上部的SQ2为仅保存部分海侵体系域沉积记录的残余层序。选择SQ1层序各体系域为等时地层单元编制层序-岩相古地理图,编图结果表明:438B区块泥盆纪具备向南东方向弧突的,由浅海陆棚、障壁岛、潟湖、潮坪组成的海湾地貌和分带性沉积格局;在各体系域继承性发展演化的分带性沉积格局中,以早期高位系域中的障壁砂坝和冲溢扇为最有利储层发育的层位、相带和部位。     

山西大同市地域开发研究

在综合分析大同市地域结构现状，地域结构水平的基础上，采用聚类定量，逻辑定性分析相结合的方法，构筑了大同市区域发展的中心－外围地域结构，指出大同市在“九五”到２０１０年期间里，生产力布局应该采取强化中心，层次推进，延展轴链，驱动叶同的“风轮式”发展战略，塑造“一心，两面，四条链”的总体格局。     

国家主体功能区空间型监测评价指标体系

对国家主体功能区开展监测和评估是掌握主体功能区规划落实情况、动态监管主体功能区运行状态的基本途径。本研究首先提出了国家主体功能区空间型监测评价指标体系概念,继而分析了指标遴选原则,即体现国家主体功能区核心功能、具备较强空间展示能力、满足管理基本需要,以及指标的可操作性、综合性与独立性等要求。在此基础上,建立了包括9个指标组和60个具体指标的体系框架。具体为:监测评价指标组包括资源、环境、生态、自然灾害、经济、人口社会、政策、交通和主体功能区运行等9个指标组;每个指标组内包含若干个可操作的具体指标。进而,还讨论了空间型监测评价指标体系的完备性与实用性、指标数据的获取方法、指标数据的空间化处理与表达等关键问题。     

广西扶绥地区那江盆地陆相层序地层初析

那江盆地是十万大山盆地北侧的一个中小型断陷盆地之一。本文根据陆相盆地层序地层的构造背景、控制因素及层序边界和内部结构特征等方面对那江断陷地层进行层序地层初析,确定出４个层序边界,划分出２个超层序（二级旋回）和３５个层序（三级旋回）;识别出冲积体系域（ＡＳＴ）、湖泊扩展体系域（ＥＳＴ）和湖泊萎缩体系域（ＲＳＴ）,初步探讨了断陷盆地层序地层的特征及其控制因素。     

Large‐scale connectivity of fluvio‐deltaic stratigraphy: Inferences from simulated accommodation‐to‐supply cycles and automated extraction of chronosomes

Multiscale simulation of fluvio‐deltaic stratigraphy was used to quantify the elements of the geometry and architectural arrangement of sub‐seismic‐scale fluvial‐to‐shelf sedimentary segments. We conducted numerical experiments of fluvio‐deltaic system evolution by simulating the accommodation‐to‐sediment‐supply (A/S) cycles of varying wavelength and amplitude with the objective to produce synthetic 3‐D stratigraphic records. Post‐processing routines were developed in order to investigate delta lobe architecture in relation to channel‐network evolution throughout A/S cycles, estimate net sediment accumulation rates in 3‐D space, and extract chronostratigraphically constrained lithosomes (or chronosomes) to quantify large‐scale connectivity, that is, the spatial distribution of high net‐to‐gross lithologies. Chronosomes formed under the conditions of channel‐belt aggradation are separated by laterally continuous abandonment surfaces associated with major avulsions and delta‐lobe switches. Chronosomes corresponding to periods in which sea level drops below the inherited shelf break, that is, the youngest portions of the late falling stage systems tract (FSST), form in the virtual absence of major avulsions, owing to the incision in their upstream parts, and thus display purely degradational architecture. Detailed investigation of chronosomes within the late FSST showed that their spatial continuity may be disrupted by higher‐frequency A/S cycles to produce “stranded” sand‐rich bodies encased in shales. Chronosomes formed during early and late falling stage (FSST) demonstrate the highest large‐scale connectivity in their proximal and distal areas, respectively. Lower‐amplitude base level changes, representative of greenhouse periods during which the shelf break is not exposed, increase the magnitude of delta‐lobe switching and favour the development of system‐wide abandonment surfaces, whose expression in real‐world stratigraphy is likely to reflect the intertwined effects of high‐frequency allogenic forcing and differential subsidence.     

海岛规划管理信息系统框架设计

为有效整合和管理各类海岛规划信息资源,针对海岛数据的特点,结合海岛规划管理和业务功能的需求,提出基于B/S和C/S的混合结构来构建规划管理信息系统的思想,设计了系统的基本框架和主要功能,探讨了系统实现过程中的关键技术,为海岛规划管理信息系统研发、综合管理和信息共享提供一个有效的解决方案。     

基于实际材料图的三维断层模型动态构建方法

三维地质模型是地质调查信息表达从传统二维平面向三维空间转变的一次重大突破。中国正在开展的三维地质填图作为国家的重要基础地质调查工作部署,将调查与研究相结合,在推动三维地质建模从研究走向实践具有重大意义。三维地质填图过程中如何准确、快速地构建三维断层模型是其中的关键点及难点。通过对数字填图过程不同阶段数据源的分析,详细分析了实际材料图建立断层数据以及与野外路线数据的关系映射规则,提出并实现了由线及面的断层模型构建方法。该方法强调断层模型构建与业务流程的一致性、动态性和快速性,构建模型的数据源始于野外第一手资料,充分利用填图业务过程中不同阶段数据的关联、约束与继承关系,能够满足在填图过程中根据地质认识的深入快速、动态地重构模型的要求,同时也可根据直观的三维断层模型时时验证地质连图的合理性。算法已在实际野外三维地质填图工作进行了多次实验,获得较好的成果。实验说明,基于实际材料图的三维断层模型构建方法与实际业务过程同步,具有操作便捷性,可直接应用于三维地质填图的实际工作要求。