鲁西汶东凹陷Qk203钻孔黏土矿物特征及其古环境

利用X射线衍射分析,对鲁西地区汶东凹陷Qk203孔沉积物中黏土矿物学特征及其古气候指示作用进行了深入研究。沉积物中黏土矿物主要为蒙脱石、高岭石和伊利石。AMS 14C测年结果、岩性组合特征、黏土矿物相对含量变化和V(Ch+I)/V(Kao+S)比值,将汶东凹陷晚更新世以来古气候环境演化划分为5个阶段,先后经历了冷干-暖湿-干凉-暖湿-进一步暖湿周期性气候旋回。其中阶段Ⅰ（2.15~0m）时代为全新世,对应于深海氧同位素MIS1（冰后期）;阶段Ⅴ～Ⅱ（33.00~2.15m）时代为晚更新世,对应于深海氧同位素MIS2（末次冰盛期）,研究表明末次冰盛期以来的气候变化具有全球性,但在不同地区会有所差异,一定程度上响应于全球古气候和中国东部古气候的变化,同时表明全球性的气候变迁对我国第四纪气候的演变起到一定控制作用,而且我国独特的构造运动也在一定程度上影响着局部气候演化进程。     

鄂尔多斯盆地侏罗系延安组煤岩特征及其主控因素分析

盆地级宏观视角的煤岩特征研究,有助于深化盆地控煤理论、全面认识盆地演化过程,同时也对于煤层生物气、直接液化用煤、富油煤等资源的分布预测及整体利用规划具有参考价值。鄂尔多斯盆地侏罗系延安组煤炭资源丰富,经历了数十载的勘查和研究,积累了丰富的煤岩资料,可供开展盆地视角的煤岩特征研究。系统收集、整理了前人鄂尔多斯盆地延安组煤岩显微组分数据,并于宁东煤田、陕北侏罗纪煤田、黄陇侏罗纪煤田分别采取了代表性煤岩样品,开展了煤岩研究和元素地球化学分析。研究结果显示,鄂尔多斯盆地侏罗系延安组煤层具有富惰质组的特征,惰质组含量与镜质组含量相当,镜质组以基质镜质体为主,含少量结构镜质体、均质镜质体和团块镜质体;惰质组以半丝质体为主,含少量氧化丝质体、粗粒体和碎屑惰质体;壳质组以小孢子体为主,还有树脂体、角质体和木栓质体。煤岩组分在平面上呈环带状分布特征,从盆地边缘向盆地中心惰质组含量降低、镜质组含量增高。延安组各煤层呈中部煤层惰质组含量较低,向上部煤层和下部煤层惰质组含量增高。对比分析表明鄂尔多斯盆地延安组为典型的坳陷型盆地环带状聚煤模式,聚煤中心与沉积中心完全分离;远离盆地中心方向,泥炭遭受的氧化时间、氧化范围和氧化强度均逐渐增大,导致惰质组含量增高;反之,靠近湖盆方向惰质组含量减少。     

Burial,Maturation, and Petroleum Generation History of the Arkoma Basin and Ouachita Foldbelt,Oklahoma and Arkansas

Removed overburden, burial, maturation, and petroleum generation analysis indicates that maturity in the Arkoma Basin and the Ouachita Foldbelt is explained effectively using simple burial models that account for the significant surface erosion that has occurred and assuming geothermal gradients similar to present-day gradients have been approximately constant through geologic time. Regional models, based on analysis at 115 well locations, indicate that from 5,000 to 15,000 ft (1.5–4.5 km) of section, differing with location from north to south and west to east, has been removed from the Arkoma Basin region, and as much as 25,000–40,000 ft (7.5–12 km) have been removed from areas of the Ouachita Foldbelt. Based on burial and thermal history reconstruction, increasing maturation from west to east across the basin is primarily the result of increasing overburden and subsequent surface erosion from west to east. The models predict most publicly available vitrinite reflectance data within a factor of 1.5 at two standard deviations. Comparison of model and measured reflectance-depth trends in six wells indicates that hydrothermal fluid movement should not have modified reflectance by more than approximately 20% in the center of the basin. Analysis indicates that most of the basin is overmature for oil production from intervals below the Spiro Sandstone, except to the north and northwest. Although thermal maturities are high, methane is stable throughout the basin. Except for the basal Arbuckle Group, all formations were thermally immature for oil generation prior to burial by the Mississippian and Morrowan in the Ouachita Foldbelt of Oklahoma and by the Atokan and Desmoinesian over most of the basin and study area. In the deeper part of the present basin, all strata entered and passed through the oil window during or within 10 My after Atokan time. Because no additional major quantities of hydrocarbons were generated after Atokan time, the hydrocarbons must have been emplaced and trapped during this brief time interval.     

喀斯特地区地表温度空间降尺度方法初探

喀斯特地区地形起伏大,常规的降尺度方法及所选择的因子对其不适用。该文根据喀斯特地区的特点,选取反射率、遥感指数及高程因子为尺度因子,通过随机森林模型建立MODIS第31、32波段辐射亮度数据和尺度因子之间的非线性关系,构建适合喀斯特地区的随机森林(Karst Random Forest,KRF)模型,成功将空间分辨率为1 km的热红外辐射亮度降至100 m,最后利用劈窗算法反演得到空间分辨率为100 m的地表温度。将KRF方法与仅考虑常规因子的多因子随机森林回归模型(MTVRF)和热锐化算法(TsHARP)对比,结果表明:1)在不同高差的喀斯特地区,KRF方法可较大程度提高地表温度降尺度精度,均方根误差(RMSE)在遵义市西北部和贵阳市以南地区分别为2.46 K和1.45 K,较MTVRF模型分别降低了0.1419 K和0.2928 K,较TsHARP算法分别降低了0.6204 K和0.6953 K,且在地形起伏度较低的喀斯特山区城市(贵阳市以南)表现更好;2)在喀斯特地区不同地类上,KRF方法效果也较好,其中植被区域最优,RMSE为1.41 K,破碎的裸土区域RMSE为1.84 K。研究显示,考虑特殊尺度因子的KRF方法可提高喀斯特地区地表温度的降尺度精度,为该地区以地表温度为基础的研究提供更精细可靠的地表温度产品。     

基于构造—地层学的隐蔽圈闭预测——以松南十屋断陷深层为例

综合运用高精度层序地层学、构造一地层学方法,认为十屋断陷深层发育的各类隐蔽圈闭是下一步勘探工作的重要目标。同时,由于构造对沉积的控制作用,在断陷内部不同的构造部位具有不同的隐蔽圈闭分布特征。十屋断陷西部皮家地区、北部张家屯一八屋地区位于油气主要运移指向区,分别由断裂坡折带和以挠曲型褶皱为特征的弯折带控制的储集砂体十分发育,盖层及保存条件也十分优越,是深部原生岩性、地层油气藏最有利的勘探目标区带。     

装载GPCTD传感器的海翼水下滑翔机观测数据实时质量控制

Profiles observed by Sea-Wing underwater gliders are widely applied in scientific research. However, the quality control(QC) of these data has received little attention. The mismatch between the temperature probe and conductivity cell response times generates erroneous salinities, especially across a strong thermocline. A sensor drift may occur owing to biofouling and biocide leakage into the conductivity cell when a glider has operated for several months. It is therefore critical to design a mature real-time QC procedure and develop a toolbox for the QC of Sea-Wing glider data. On the basis of temperature and salinity profiles observed by several Sea-Wing gliders each installed with a Sea-Bird Glider Payload CTD sensor, a real-time QC method including a thermal lag correction, Argo-equivalent real-time QC tests, and a simple post-processing procedure is proposed. The method can also be adopted for Petrel gliders.     

氧同位素分析在东濮凹陷下第三纪沉积环境中的应用

主要介绍了氧同位素的地球化学特征，并利用这些特征在沉积环境方面的指示意义，分析了东濮凹陷下第三系盐湖沉积的氧同位素。分析结果表明：尽管保存在碳酸盐中的氧同位素的值不能定量地反映原始氧同位素的值，不能够作为区分海陆相的标志，但它可以定性地探讨碳酸盐沉积时的沉积环境。通过对东濮凹陷下第三系盐湖沉积的氧同位素分析发现，从沙四上到沙一时期，除了沙三上的δ^18O有些突变外，基本上呈递增趋势。这反映出，从沙四上到沙一时期该区的气候逐渐向干早过渡；沙四上到沙三上一段δ＾18Ｏ明显比沙一和沙二上伯低，说明在沙四上到沙三上时期，该沉积区的蒸发作用还不是很显著，而另一方面也说明在由沙三上向沙二上过渡时，该区可能存在一次气候突变，使得沙二上和沙一时期的蒸发量远大于降雨量，δ^18O的值也因此迅速增大。同时，也做了碳酸盐同位素系数Z值的研究，其揭示的沉积环境特征与氧同位素基本相同。     

大民屯凹陷地层水水文地质特征与油气聚集关系

对大民屯凹陷前第三系潜山、下第三系沙河街组地层水化学场研究发现，本区油田水总矿化度及二价阳离子浓度偏低，地层水总矿化度具有明显的垂向分带性，水体主要为陆相成因并受地表水渗入的影响较大，变质程度高，油田水的演化与盐类的溶解有关。该区地层水的流动受断裂和沉积砂体的控制，在水头压力、浮力动力场控制下其流动样式和分布规律反映了凹陷内油气的运聚规律，可为本区自生自储、新生古储式油气藏的判别提供有利证据。