准噶尔盆地西北缘中拐凸起断裂发育特征及构造变形过程

中拐凸起地区经历了多期构造运动,构造叠加效应强烈,断裂系统复杂,亟待厘定。针对上述问题,采用断裂系统分析技术,建立了中拐凸起早期发育压扭断层、晚期发育正断层的"两期叠加断裂发育模式"。平衡剖面分析认为,受区域性构造转换影响,该地区主要经历了5个构造演化阶段:基底隆升阶段、挤压变形阶段、构造转换阶段、伸展改造阶段和构造定型阶段。中拐凸起形成于挤压应力环境,内部发育压扭断层;在晚期伸展条件下,凸起内部发育大量正断层。浅部正断层与深部压扭断层构成纵向叠加,沟通源储,影响成藏。     

Reservoir petroleum inclusion GOR characteristics and geological significance from the Lunnan Low Uplift of the Tarim Basin

There were different opinions about the origin of petroleum property variations in the Lunnan Low Uplift of the Tarim Basin. In this paper, a software PVTsim was applied to investigate the compositions of the petroleum fluid inclusions in different sets of reservoir rocks from this area. The results show that there are three phases of petroleum inclusions in the Ordovician carbonate reservoirs and two types of petroleum inclusions in the Carboniferous and Tri-assic sandstone reservoirs. The three phases of the petroleum inclusions from the Ordovician reservoir rocks have similar compositions with the type 1 petroleum inclusion from the carboniferous and Triassic reservoir rocks, but the type 2 petroleum inclusion from the carboniferous and Triassic reservoirs is characterized by higher content of C1 and higher GOR values. With the combination of the geological background, it was inferred that the current petroleum pools in the Lunnan Low Uplift were formed mainly by two phases of petroleum charges, one is normal oils and another light oils, and both occurred during the late Tertiary. The light oils came from eastern-south direction, and migrated and charged into the reservoirs upward and toward northern west directions. On the basis of this, it was believed that the multiphases of the petroleum charges and some composition dissipation caused by the preserved condition changes would be the main reason of the petroleum property variations in the petroleum pools in this area.     

地层结构外延法在塔中隆起古生界多期剥蚀量估算中的应用

许多常用的剥蚀量估算方法存在着局限性.这些方法通常只能估算某一界面的总剥蚀量或者在单期构造活动区估算剥蚀量.采用地层结构外延法,探讨具有多期剥蚀历史的剥蚀量估算.地震剖面综合研究揭示,塔中地区存在3个主要剥蚀界面.对3个主要构造变革期剥蚀量的剖面和平面分布特征的分析表明,塔中地区剥蚀量的分布主要受构造控制;不同时期的剥蚀量分布差异,反映了该区的古剥蚀地貌特征和构造发育演化过程.     

云岭隧道仰拱填充隆起变形的原因分析及处理对策

十(堰)漫(川关)高速公路云岭隧道处在活动断裂构造带附近,受地质、高地应力、设计因素及施工因素的影响,造成已施工的仰拱填充隆起变形,对施工质量及安全造成较大影响,为以后的运营埋下较大的安全隐患。本文针对已施工的仰拱填充隆起变形现象,通过对技术上的监测,全面分析导致这次起拱变形的具体原因,并提出了相应的技术方案进行处治,取得了较好的效果。     

西昆仑山北缘新生代隆升历史的裂变径迹证据

自新生代以来,西昆仑地区发生强烈的构造变形和隆升,其初始隆升和末次快速隆升的时限仍是有待探讨的重大问题。本文沿西昆仑北缘采集一系列砂岩样品,利用裂变径迹分析方法探讨了西昆仑北缘新生代的冷却历史。结合裂变径迹年龄和径迹长度分布进行分析,可以将6个磷灰石样品分为2组。3个磷灰石样品的径迹年龄远小于所在地层的年龄。平均径迹长度为(12.0±2.3)~(12.6±1.3)μm,呈不对称单峰形态,反映样品缓慢地通过部分退火带;另外3个磷灰石样品径迹年龄与各自地层的沉积年龄接近,平均径迹长度介于(10.7±2.3)~(11.4±1.3)μm,呈现双峰或混合分布的特征,表明沉积后发生部分退火。热史模拟显示,自晚白垩世以来,西昆仑山北缘共经历了3期抬升冷却事件。晚始新世(40~30 Ma),受早期印度板块向古亚洲大陆板块俯冲碰撞的影响,西昆仑山北缘已经开始隆升;晚渐新世―早中新世(25~15 Ma)是西昆仑乃至青藏高原重要的隆升时期;最后一轮强烈隆升则发生在距今5~3 Ma以来,冷却速率最高达15℃/Ma,剥蚀速率相当于600m/my。电子自旋共振测试揭示了早中新世(15 Ma)和晚上新世以来(2.6~0.63 Ma)两期强烈的构造变形和热液活动,更进一步限定了西昆仑最后一期强烈隆升在2.6 Ma以来。     

青藏高原隆升与陇中盆地地文期

陇中盆地位于青藏高原的东北边缘地区，宏观上它同一系列次级新生代盆地构成，青藏高原的阶段性隆升影响，制约着它的形成，发育和演化，盆地中普遍存在多级台阶式的地貌结构实则是此地区区域地貌发育阶段的记录，是地文期研究的最佳材料，本文在前人研究的基础上之，根据最新的研究成果，补充划分了本地区新世以来的地文期序列，自上新世以来，陇中地区至少经历了十次区域地貌发育阶段，且与青藏高原的阶段性隆升密切相关。     

江南隆起带皖赣相邻区燕山期岩浆岩稀土对比研究

对比研究了江南隆起带皖南地区与赣东北地区燕山期岩浆岩的稀土元素地球化学特征，稀土元素特征反映出，皖南地区燕山期岩浆岩属于典型的壳源岩浆岩，而赣东北地区燕山期岩浆岩则具有幔源特征，这是赣东北地区燕山期与岩浆岩有关的多金属矿床发育、而皖南地区不发育的重要原因。稀土元素的研究结果同时得到地球物理、成岩构造背景、稳定同位素等研究的证实，也表明稀土元素在岩浆岩成岩物质来源方面有很好的示踪作用。     

桩的抗拔承载力预估

在对抗拔试桩资料整理与分析的基础上，详细讨论了抗拔桩粘羊力系数ａ与桩周土不排水抗剪强度Ｃｕ的关系及桩拔、压摩阻比与桩长径比的关系，以及桩周土的土性、桩的类型和施工方法等对它们的影响，并提出了预估桩抗拔承载力的方法。     

Accumulation process and model for the Ordovician buried hill reservoir in the western Lunnan area,the Tarim Basin

The Ordovician buried hill reservoir in the western Lunnan area, a type of dissolved fracture and cavernous reservoir, is mainly composed of heavy oil. The oil is the mixture sourcing from the Middle-Lower Cambrian and Middle-Lower Ordovician, with three stages of pool forming process: (1) the destruction and parallel migration/accumulation during the late Caledonian to early Hercynian; (2) the oil and gas accumulation during the late Hercynian characterized by adjustment upward along faults and parallel migration/accumulation; (3) the formation of heavy oil during the latest Hercynian. The Ordovician buried hill reservoir is affected by the diffusion of light oil and gas but had no hydrocarbon charging during the late Yanshan period to Himalayan period, but in this period, formed the association of heavy oil and dissolved gas cracked from crude oil with dry coefficient of 0.91-0.96. The study on accumulation process of the Ordovician buried hill reservoir has important implications for the exploration potential of early oil and gas accumulation in the cratonic area of the Tarim Basin.     

番禺隆起新近系层序、沉积演化与地层圈闭

综合分析钻井、地震等资料,将区内新近系划分为14个三级层序,每个层序又可以海泛面为界细分为3～5个四级层序或体系域.层序界面和水进面与浮游有孔虫的丰度和分异度变化有密切关系.结合钻井约束的地震沉积学分析,可识别出低位域(辫状河)三角洲、河流三角洲、浅海陆棚等沉积体系.地层属性分析揭示了三角洲前缘沉积在平面上特有的环状结构.以四级层序为地层单元的沉积相平面编图可很好地反映不同体系域的沉积相演化.区内的层序结构和沉积相带演化主要受到海平面变化的控制.区内存在5种潜在的岩性地层或构造-地层圈闭,由断裂坡折带控制的低位域三角洲砂体已由勘探证实可形成重要的构造-地层油气藏.