地层古厚度定量恢复方法研究及应用——以准噶尔盆地陆东地区为例

文章提出了一种地层古厚度恢复的方法,利用该方法恢复了研究区的埋藏演化历史;根据该方法恢复后的地层古厚度制作的埋藏史曲线真实地展现了该区经历了“两快两慢、三次抬升”的埋藏演化过程;分析认为该区的埋藏史可以分为2种类型持续沉降型和早期快速沉降型。其中,早期快速沉降型能否成为油气成藏的关键是保存条件。通过上述研究发现石炭系烃源岩在侏罗系八道湾组沉积末期开始生、排烃,在西山窑组沉积末期达到成熟—高成熟,开始大量的生、排烃。

准噶尔盆地陆东地区巴塔玛依内山组火山喷发时空序列及其石油地质意义

石炭纪期间准噶尔盆地陆东地区作为相对独立的增生楔盆地进行富火山岩化充填演化,早石炭世晚期陆东地区进入碰撞后应力松驰期,发育区域性巴塔玛依内山组火山岩储层。通过井间对比和野外露头观察、地球化学和地球物理识别认为:陆东地区巴塔玛依内山组为一套低钾富钠碱性—亚碱性系火山岩,巴山组内部发育5个火山喷发旋回,自下向上火山活动逐渐减弱,并且在火山机构不同位置形成不同岩相组合方式;火山机构区带控制火山岩岩相分布,主火山机构以西发育中—基性安山岩和玄武岩;而火山中心以东发育有喷发相火山角砾岩和溢流相玄武岩或流纹岩;火山喷发时序内的火山间歇停滞期,有利于发育局部烃源岩和巴山组内幕火山岩风化壳储层,为陆东地区石炭系"自生自储"油气藏提供必要的生储条件。

准噶尔盆地陆东地区石炭系火成岩内幕油气资源潜力

近年来在准噶尔盆地陆东地区石炭系火成岩储集层中发现了大量的油气,显示了巨大的勘探潜力。然而已探明或已获得的工业性油气流主要分布在石炭系顶部的风化壳储集层中,而在火成岩内幕储集层中虽见到大量油气显示,但未获得工业性油气流,因此,分析该地区火成岩内幕油气的勘探潜力,对下一步的油气勘探具有重要的指导意义。通过对石炭系火成岩内幕和风化壳储集层特征及油气勘探潜力的对比研究表明,石炭系火成岩孔隙度随着距离石炭系顶部不整合面距离的增加出现两个波峰,分别对应两个次生溶蚀带,第一个波峰对应的为火成岩风化壳储集层,第二个波峰对应的为火成岩内幕储集层;内幕天然气资源量为1 750×108m3;斜坡带为陆东地区石炭系火成岩内幕气藏发育的有利区域。

陆东地区构造几何学和构造运动学分析

陆东地区构造几何学分析认为 :多期次、多类型、同生、早期右行、晚期左行是该区断裂的主要特征 ;构造运动学分析认为 :中海西期以来的各期构造运动直接控制了该区的沉积与构造演化特征 ,各期构造运动各具特色。通过研究还发现 。

准噶尔盆地陆东地区白垩系储层特征及其主控因素

从岩石学特征、成岩作用、孔隙类型、结构特征以及储层性质的主要影响因素等方面 ,对准噶尔盆地陆东地区白垩系储层进行了研究。结果表明 ,储层岩石为长石质岩屑砂岩 ,成岩作用进入早成岩B亚期 ;孔隙类型主要为原生残余粒间孔 ,另有少量的溶蚀孔及微孔隙。该储层孔隙结构非均质性强 ,呼二段中粗孔喉最多 ,呼一段次之 ,连木沁组多为中孔细喉和较细喉 ,清水河组为细孔、细喉。储层性质差别较大 ,呼一段、呼二段为中孔、中渗储层 ,连木沁组为低孔、低渗储层 ,清水河组为低孔、特低渗储层。储层性质主要受沉积相、古气候、压实作用及砂岩粒径等因素的影响。

准噶尔盆地陆东地区侏罗系剥蚀厚度恢复

恢复地层剥蚀厚度的方法众多,但它们都有或多或少的使用条件。针对准噶尔盆地陆东地区的资料条件和地质条件,采用邻层厚度比值法,并结合传统的沉积速率法,对侏罗系地层剥蚀厚度进行恢复。从恢复结果来看,西山窑的剥蚀厚度盆地中央厚四周薄,其中石南凹陷、三南凹陷、乌伦古凹陷及该区南缘几乎未被剥蚀;头屯河组的大部分地层均被剥蚀。这一恢复结果与当时的沉积、构造环境基本吻合,从而证明了这种方法是切实可行的。

用建场测深技术研究陆东地区石炭系火山岩结构特征

建场测深是一种采用大功率人工场源激发,具较高分辨率和勘探精度的电法勘探新技术。建场测深剖面对陆东地区石炭系内幕结构反映较为清晰,其电性结构揭示上石炭统发育上、下2套火山岩序列,中间为沉积岩层间隔,并能够反映火山岩序列内部岩性的横向变化及火山构造的发育情况。不同地区石炭系残留程度不同,相应的地层电性结构存在明显差异。在北疆石炭系勘探领域,建场测深技术具有较好的应用效果,为地震勘探起到重要补充作用。

准噶尔盆地陆东地区石炭系地震波组及构造-地层层序特征

利用最新钻井与地震资料,对准噶尔盆地陆东地区石炭系的地震波组特征展开研究,在此基础上划分了研究区构造-地层层序。通过分析对比30口井的合成地震记录,识别出4个主要反射界面:T_0,T_1,T_2和T_3。T_0和T_2界面反射波振幅强、连续性好、波形稳定,为本区主要的区域性不整合,也是关键的可对比标志层。在此基础上,总结了4个反射界面间各地震地层的波组特征,其中T_1与T_2之间的反射波组整体振幅弱、中-低频和中-差连续,反射外形呈楔状,可作为陆东地区对比的标志层。在不整合面追踪的基础上,结合露头、古生物资料和年代学资料等,将研究区石炭系划分为4套构造层,从下至上分别为:下沉积岩段C_1-s(滴水泉组)、下火山岩段C_1-v(松客尔苏组下亚组)、上沉积岩段C_2-s(松客尔苏组上亚组)和上火山岩段C_2-v(巴山组)。研究认为,石炭系各构造层的分布受基底、构造背景、发育位置及后期改造作用的控制,在弧内断陷和弧前盆地等部位发育的厚度相对较大,在岛弧凸起部位厚度较小;早、晚石炭世末发育的两期构造挤压运动,导致C_1-v与C_2-s之间的地层及C_2-v构造层顶部遭受剥蚀,并使石炭纪断陷发生反转。

准噶尔盆地陆东—五彩湾地区石炭系烃源岩

陆东—五彩湾地区天然气具有典型的源控成藏特征,将露头资料、钻井资料和地震资料相结合,对陆东—五彩湾地区石炭系烃源岩的丰度、类型、成熟度特征进行了系统研究和评价。研究区石炭系烃源岩以深灰色泥岩和灰色泥岩为主,其次为凝灰岩、炭质泥岩、粉砂质泥岩和煤;上石炭统巴塔玛依内山组(C2b)烃源岩丰度高于下石炭统滴水泉组(C1d),下石炭统烃源岩的类型好于上石炭统;石炭系烃源岩成熟度高值区分布在滴南凸起西段—五彩湾凹陷一带,向南、北方向石炭系烃源岩的成熟度降低;石炭系烃源岩与火山岩的分布具有互补性,烃源岩呈东西向带状分布,烃源岩最发育区位于滴南凸起西段及其南部。

准噶尔盆地陆东-五彩湾地区石炭系中、基性火山岩地球化学及其形成环境

准噶尔盆地是发育在前寒武纪结晶基底与古生代褶皱基底双重基底之上的中、新生代沉积盆地。盆地东北缘陆东—五彩湾地区发育大量的石炭系中、基性火山岩,主要由玄武岩、熔结玄武岩、气孔-杏仁玄武岩与辉绿岩组成。其中、基性火山岩具有低钾高钛、高∑REE的特征,球粒陨石标准化的REE配分曲线表现轻稀土富集,轻、重稀土分异的谱线特征,微量元素具有大离子亲石元素富集,Ta、Nb亏损的现象,可能与板内拉张环境下地壳混染或地幔源区有富Ta、Nb的残留体有关,微量元素环境判别图解中大部分样品点落入板内玄武岩区域,少量漂向岛弧火山岩区,表现出主体为板内构造环境;高场强元素Th/Nb、Nb/Zr比值进一步表现出火山岩具有板内火山岩的特征。综合区域地质特征及前人的研究结果,认为准噶尔盆地陆东—五彩湾地区中、基性火山岩应属造山期后伸展背景下的火山作用产物,但岩浆源区可能受到古洋壳板片俯冲作用的影响。

陆东-五彩湾地区石炭系火山岩气藏勘探进展

为进一步加大对准噶尔盆地石炭系火山岩这一新型储层的研究力度,依据前人的认识和勘探成果,通过对该盆地陆东—五彩湾地区火山岩岩性特征、生烃潜力、储盖组合的深入研究,结合多种资料的分析结果,建立了该区的岩性岩相识别模式,划分了有利火山岩分布范围,开展了整体研究,并优选目标实施钻探获得了成功。以滴南凸起为主攻目标,其中,滴西14井是整体解剖滴南凸起后优选钻探的第一口预探井。该井射开石炭系压裂后,获日产天然气16×104m3的高产工业气流,发现了滴西14井石炭系火山岩天然气藏。该气藏属基岩块状气藏,依据岩相识别模式圈定含气面积37km2,预测天然气地质储量642×108m3。

准噶尔盆地陆东-五彩湾地区石炭系源岩演化及成藏时序

陆东-五彩湾地区石炭系源岩呈带状分布，源岩最发育区位于滴南凸起西段及其南部。不同地区石炭系源岩成熟度差异较大，成熟度中心沿滴南凸起西段-五彩湾凹陷北西向展布，向南、向北成熟度降低。通过源岩热演化史及包裹体温度，综合分析了该区的油气成藏过程。不同区块表现出明显的成藏时序性，第一期成藏时间由早到晚的顺序依次是五彩湾-滴南西段-滴南东段-滴北地区。源岩分布、演化及成藏时序控制了该区的油气分布。

Carbon Sequestration Effects of Shrublands in Three-North Shelterbelt Forest Region, China

Three-North Shelterbelt Forest （TSF） program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that： 1） The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10^7 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2） In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo vat. heterophylla. The carbon sequestration of/-/, rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3） The total carbon sequestration of shrubland in the study region was 4.5 x 107 Mg C with a mean annual carbon sequestration of 1.5× 10^6 Mg C. The carbon density in the four sub-regions decreased in the following order： the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a baseline reference for future research in this area.

Land cover change and carbon stores in a tropical montane cloud forest in the Sierra Madre Oriental,Mexico

Tropical montane cloud forest is one of the ecosystems with the highest biomass worldwide, representing an important carbon store. Globally its deforestation index is –1.1%, but in Mexico it is higher than –3%. Carbon estimates are scarce globally, particularly in Mexico. The objective of this study was to simulate future land-cover scenarios for the Sierra Madre Oriental in Mexico, by analyzing past forest cover changes. Another objective was to estimate stored carbon in the two study areas. These objectives involve the generation of information that could be useful inputs to anti-deforestation public policy such as the REDD+ strategy. Remote sensing was used to measure land cover change and estimate carbon stocks. Satellite images from 2015, 2000 and 1986 were used, and Dinamica EGO freeware generatedmodels of future projections. Between 1986 and 2015, 5171 ha of forest were converted to pasture. The annual deforestation rates were –1.5% for Tlanchinol and –1.3% for the San Bartolo Tutotepec sites. Distance to roads and marginalization were highly correlated with deforestation. By 2030, an estimated 3608 ha of forest in these sites will have been converted to pasture. Stored carbon was estimated at 16.35 Mg C ha-1 for the Tlanchinol site and 12.7 Mg C ha-1 for the San Bartolo site. In the Sierra Madre Oriental deforestation due to land cover change(–1.4%) is higher than levels reported worldwide. Besides having high values of stored carbon(14.5 Mg C ha-1), these forests have high biodiversity. The models' outputs show that the deforestation process will continue if action is not taken to avoid the expansion of livestock pasturing. This can be done by paying incentives for forest conservation to the owners of the land. The results suggest that REDD+ is currently the most viable strategy for reducing deforestation rates in tropical montane cloud forests in Sierra Madre Oriental.

Structure and Ownership of Agricultural Land in Poland in the First Years of New Millennium

Poland is characterized by a high relations, existing in the past, low level of overpopulation. Concentration of agricultural share of agricultural land in total surface. economic development, compared to the land is observed on areas with fertile soils This is the effect of the socio-economic countries of Western Europe, and rural and in the less industrialized central and eastern parts of the country. The lowest shares of agricultural land are observed on areas featuring natural conditions disadvantageous for farming, the highly forested North-Western Poland, and the areas characterized by high degree of industrialization and urbanization. The contemporary ownership structure in Poland is the effect of historical transformations of the social, economic and political relations. The pattern of the ownership structure developed over the centuries, and it is the resultant of the diverse socio-economic processes.

Origins of Terrestrial Organic Matter in Surface Sediments of the East China Sea Shelf

Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon cycle. A novel approach combining molecular proxies and compound-specific carbon isotopes is used to quantitatively constrain the origins and transport mechanisms of TOM in surface sediments from the ECS shelf. The content of terrestrial biomarkers of(C_(27)+C_(29)+C_(31)) n-alkanes(52 to 580 ng g^(-1)) revealed a seaward decreasing trend, the δ^(13)CTOC values(-20.6‰ to-22.7‰) were more negative near the coast, and the TMBR(terrestrial and marine biomarker ratio) values(0.06 to 0.40) also revealed a seaward decreasing trend. These proxies all indicated more TOM(up to 48%) deposition in the coastal areas. The Alkane Index, the ratio of C_(29)/(C_(29)+C_(31)) n-alkanes indicated a higher proportion of grass vegetation in the coastal area; While the δ13C values of C_(29) n-alkane(-_(29).3‰ to-33.8‰) indicated that terrestrial plant in the sediments of the ECS shelf were mainly derived from C_3 plants. Cluster analysis afforded detailed estimates of different-sourced TOM contributions and transport mechanisms. TOM in the Zhejiang-Fujian coastal area was mostly delivered by the Changjiang River, and characterized by higher %TOM(up to 48%), higher %C_3 plant OM(68%-85%) and higher grass plant OM(56%-61%); TOM in the mid-shelf area was mostly transported by aerosols, and characterized by low %TOM(less than 17%), slightly lower C_3 plant OM(56%-72%) and lower grass plant OM(49%-55%).

Suspended sediment concentration mapping based on the MODIS satellite imagery in the East China inland, estuarine, and coastal waters

The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration(SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra R_(rs)(λ) after atmospheric correction; 2) an estimation of R_(rs)(λ) from the radiometric signals above the air-water surface; and 3) an estimation of SSC from R_(rs)(λ). Six different models for radiometric R_(rs)(λ) determination and 28 models for SSC versus R_(rs)(λ) are analyzed based on the field observations made in the Changjiang River estuary and its adjacent coastal area. The SSC images based on the above-mentioned analysis are generated for the area.

Sedimentological features and biostratigraphy of Jurassic/Cretaceous deposits in continental basins in Priamurie,Far East Russia

The paper describes the sedimentary features and biostratigraphy of the transitional Jurassic to Cretaceous deposits in the continental basins of Priamurie formed after the collision between the Siberian and North China blocks. In Upper Priamurie, the collision occurred in the late Early Jurassic as dated by the emplacement of the post-collisional granites （ 191 Ma）. While in Lower Priamurie and West Priokhotie it could take place in the late Middle Jurassic on the basis of fossil evidence from an aceretionary turbidite complex. This event reflected the environmental change from coastal-marine to alluvial plains, often boggy, where coals aecmnulated. The environinental change is in harmony with that of biota. Systematic study of floral and spores/pollen assemblages, particularly in the sections of interbedded marine and non-marine deposits, makes clear the chronostrati-graphic succession of floral associations and shows the possibility of their application for subdivision and correlation of the continental deposits of Priamurie. Tire coastal-marine environment of the residual post-collisional sublatitudinal basins in the uestern part of Priamurie （Upper Amur and Dep basins） was replaced by the continental in the late Middle Jurassic and in the eastern part in the Berriasian-Valanginian （Torom Basin）. Similar environmental change commenced in the submeridional rift basins： the Bureya Basin in the Callovian and the Partizansk Basin in the Hauterivian. Changes in ecosystems ocemTed frequently during the Middle Jurassic-Ne- ocomian, but the most substantial changes took place in the late Middle Jurassic and in the end of Late Jurassie.

Seismic volcanostratigraphy of large, extrusive complexes in continental rift basins of Northeast China：Analysis of general bedding patterns in volcanostratigraphy and their seismic reflection configurations

The aim of this work is to establish volcanic seismic reflection configuration models in the rift basins of Northeast China from a new perspective,the volcanostratigraphic structure.Accordingly,the volcanostratigraphic structure of an outcrop near the Hailaier Rift Basin was analyzed to understand the characteristics and causal factors of physical boundaries.Further,3D seismic reflection data and analysis of deep boreholes in the Songliao Rift Basin were used to establish the relationship between volcanic seismic reflection configurations and volcanostratigraphic structures.These studies suggested that in volcanic successions,physical boundaries coincide with volcanic boundaries,and their distributions are controlled by the stacking patterns of volcanic units.Therefore,volcanic seismic reflection configurations can be interpreted in terms of the stacking patterns of volcanic units.These are also referred to as general bedding patterns in volcanostratigraphy.Furthermore,four typical seismic reflection configurations were identified,namely,the chaotic,the parallel continuous,the hummocky,the multi-mound superimposed and the composite.The corresponding interpretation models comprised single massive unit,vertical,intersectional,lateral multi-mound,and composite stacking patterns.The hummocky and composite reflection configurations with intersectional and composite stacking patterns are the most favorable for the exploration of volcanic reservoirs in rift basins.

Extracting Eco-hydrological Information of Inland Wetland from L-band Synthetic Aperture Radar Image in Honghe National Nature Reserve, Northeast China

Taking a typical inland wetland of Honghe National Nature Reserve (HNNR), Northeast China, as the study area, this paper studied the application of L-band Synthetic Aperture Radar (SAR) image in extracting eco-hydrological information of inland wetland. Landsat-5 TM and ALOS PALSAR HH backscatter images were first fused by using the wavelet-IHS method. Based on the fused image data, the classification method of support vector machines was used to map the wetland in the study area. The overall mapping accuracy is 77.5%. Then, the wet and dry aboveground biomass estimation models, including statistical models and a Rice Cloudy model, were established. Optimal parameters for the Rice Cloudy model were calculated in MATLAB by using the least squares method. Based on the validation results, it was found that the Rice Cloudy model produced higher accuracy for both wet and dry aboveground biomass estimation compared to the statistical models. Finally, subcanopy water boundary information was extracted from the HH backscatter image by threshold method. Compared to the actual water borderline result, the extracted result from L-band SAR image is reliable. In this paper, the HH-HV phase difference was proved to be valueless for extracting subcanopy water boundary information.