The Devonian–Lower Carboniferous succession in Northwest Peninsular Malaysia

A new stratigraphic nomenclature is proposed for the approximately 600 m thick, mainly clastic transitional sequence between the underlying Mempelam Limestone and overlying Kubang Pasu/Singa Formation in northwest Peninsular Malaysia. This sequence represents shallow marine deposits of the continental margin of the Sibumasu Terrane during the Middle Palaeozoic (Devonian–Carboniferous). It is separated into several formations. The Timah Tasoh Formation is an approximately 76 m sequence consisting of 40 m of laminated tentaculitid shales at the base, containing Monograptus yukonensis Jackson and Lenz and Nowakia (Turkestanella) acuaria Alberti, giving an Early Devonian (Pragian–Emsian) age, and about 36 m of rhythmically interbedded, light coloured argillo-arenites. The Chepor Formation is about 90 m thick and consists mainly of thick red mudstone interbedded with sandstone beds, of Middle to Late Devonian age. A new limestone unit is recognized and named the Sanai Limestone, which contains conodonts of Famennian age. The Binjal Formation consists of red and white mudstone interbedded with sandstone beds showing Bouma sequences. The Telaga Jatoh Formation is 9 m thick and consists mainly of radiolarian chert. The Wang Kelian Formation is composed of thick red mudstone beds interbedded with silty sandstone, and contain fossils indicative of an Early Carboniferous (Visean) age. The succession was deposited on the outer shelf, with depositional environments vertically fluctuating from prodelta to basinal marine. The Devonian–Carboniferous boundary is exposed at Hutan Aji and Kampung Guar Jentik, and indicates a major regressive event during the latest Devonian.     

Methodology for preliminary seismic design of extended pile‐shafts for bridge structures

Seismic design of extended pile‐shafts requires a careful consideration of the influence of the surrounding soil on the overall response of the soil–pile system. In this paper, a procedure that incorporates soil properties into the process is developed for preliminary seismic design of extended pile‐shafts. The method follows the well‐accepted approach of using a force reduction factor to determine the lateral strength of the structure. The procedure involves an iterative process to arrive at the required amount of longitudinal reinforcement. Other outcomes of the procedure include the appropriate lateral stiffness and strength, as well as an estimation of the local curvature demand and ultimate drift ratio that can be used to ensure a satisfactory lateral response. The design procedure is capable of providing reliable results for a practical range of structural and soil properties. The versatility of the procedure is illustrated using two numerical examples of extended pile‐shafts constructed in different soil sites. Copyright © 2006 John Wiley & Sons, Ltd.     

试论土地侵蚀

建议用“土地侵蚀”一词取代“水土流失”这个术语．土地侵蚀是地球陆地表面的固体组成物质（岩土体）在内外营力和人为作用下，发生的风化、运移和堆积过程．按土地利用实情，土地侵蚀分为土壤侵蚀、矿山侵蚀、道路侵蚀、城镇侵蚀、岸坡侵蚀和本利用地侵蚀等．     

我国南方土地侵蚀特点

境内土地侵蚀严重，以水蚀为主，其面积６８３３２０ｋｍ２，占全国水蚀面积的３８％．讨论了：滑坡、泥石流侵蚀；碳酸盐岩、花岗岩和红层各具特色的侵蚀；土地侵蚀的危害严重，石化面积在扩大，中小河道淤高；塘库、湖泊遭淤，容积缩小；南方土地侵蚀泥沙输移比较小．     

甘改—玉树断裂带的近代地震与未来地震趋势估计

通过对甘改－玉树断裂带上近代地震的震级，震中位置和地震地表破裂的空间展布特征的研究，采用Ｎｉｓｈｅｎｋｏ和Ｂｕｌａｎｄ发展的“特征地震复发时间通用分布”概率模型，即“ＮＢ”模型，对甘孜玉树断裂带各段落未来５０ａ内强震趋势进行了估计。     

石油资源的定量评价预测

本文涉及石油资源的定量评价预测。文中介绍了六种方法:随机过程法、搜索区分析法、油田规模分布的极大似然估计法、蒙特卡洛法、经验分布变换法、模糊综合评判法。这些方法在我国中部一个油田石油资源评价预测中得到应用并获得了满意的结果。     

Experimental Study of Synthesis Processing System for Rock Acoustical Measurement

The system consists of SYC rock acoustical measurement instrument, microcomputer and single board computer. It is a building block system used in both laboratory and field testing to measure rock acoustical data. In this paper the main performances, the fundamental configuration, the interface technique and software design methods are presented, and measurement result analysis is made. An idea was proposed of the automatic acquisition and processing of test data by means of micro-computer control over the test device.     

Thermochemistry of carbonate-pyroxene equilibria

The enthalpies of drop solution of calcite, magnesite, dolomite, wollastonite and diopside have been measured in a lead borate solvent at 977 K in a Calvettype microcalorimeter. The carbonate calorimetry was done under flowing gas atmosphere. Both natural and synthetic samples were used. From these calorimetric data, the enthalpies of several reactions of carbonate with quartz were calculated. The enthalpies of these reactions (kJ/mol) at 298 K are: calcite+quartzwollastonite+CO₂, 92.3±1.0; magnesite+quartzenstatite+CO₂, 82.9±2.8; dolomite+quartzdiopside+CO₂, 163.0±1.9. These values generally are in agreement with those calculated from Robie et al., Helgeson et al., Berman and Holland and Powell. The enthalpy of dolomite-quartz reaction overlaps marginally with those from Berman and Holland and Powell. The enthalpy of formation of dolomite from magnesite and calcite (-11.1±2.5 kJ/mol) was also derived from the measured enthalpies, and this value is consistent with that from acid solution calorimetric measurements as shown by Navrotsky and Capobianco, but different from values in the earlier literature. These results support the premise that drop-solution of carbonates into molten lead borate results in a well-defined final state consisting of dissolved oxide and evolved CO₂. This was also confirmed by weight change experiments. Thus, oxide melt calorimetry is applicable to carbonates.     

Assessment of seismic performance of extended pile‐shafts

The seismic performance of extended pile‐shafts subjected to the current level of displacement ductility demand is assessed for different soil conditions. Local curvature ductility demand is compared with the curvature ductility capacity provided by the current level of confining steel. Parameters in the assessment of extended pile‐shafts include the undrained shear strength of cohesive soils, relative density of cohesionless soils, aboveground height, longitudinal reinforcement ratio, axial force level and pile diameter. Results indicate that the curvature ductility demand in the pile decreases with increased soil stiffness but increases with increased aboveground height. The curvature ductility demand however is not sensitive to the longitudinal reinforcement ratio or axial force level, and is independent of the pile diameter. Results further indicate that the curvature ductility capacity available from the current level of confining steel may not be adequate for tall extended pile‐shafts, especially for piles with large longitudinal reinforcement ratio and embedded in soft or loose soils. Limits on the maximum longitudinal reinforcement ratio are suggested in the paper. Copyright © 2003 John Wiley & Sons, Ltd.