The Coarse-Grained Lacustrine Slope Apron Deposits in the Moliqing Area,Yitong Basin,Northeast China

Overlapping gravity accumulation bodies were formed on the northwestern steep slope of the Shuangyang Formation in the Moliqing fault depression of northeast China.This study analyzed in detail the spatial distribution of the lithofacies and lithofacies associations of these accumulation bodies based on more than 600 m of core sections,and summarized 12 major types of lithofacies and three types of lithofacies associations：（1） the proximal zone consists of gravelly debris flows dominated by alluvial channel conglomerates;（2） the middle zone is dominated by various gravity flow deposits and traction flow deposits;and（3） the distal zone is dominated by mudstones with intercalations of sandy debris and turbidites.Combining with the grain size cumulative probability curves analysis,we determined the transformation of debris flows to sandy debris flows and to turbidity currents in the slope zone of the basin margin,and further proposed a lacustrine slope apron model that is characterized by（1） an inconstant multiple source（line source）,（2） an alternation of gravity flow deposits and traction flow deposits dominated by periodical changes in a source flood flow system,and（3） the transformation of sandy debris flow deposits into distal turbidity current deposits.This sedimentary model may be applicable to other fault depressions for predicting reservoir distribution.

Tectonic uplift history of the Yitong Basin since the Oligocene,Northeast China:Evidence from apatite fission track ages and geological relationship

The Yitong Basin is an oilbearing basin with unique characteristics in Northeast China. On the basis of apatite fission track ages and geological relationship, the tectonic uplift history of the Yitong Basin since the Oligo-cene was discussed. Based on apatite fission track analysis of five samples from the Luxiang and Chaluhe fault depressions and basin modeling study, it can be concluded that since the Oligocene (36.6 Ma) in the Yitong Basin, the Chaluhe fault depression has undergone two episodes of uplift during 24.9-19.1 Ma and 6.9-4.9 Ma. And the Luxiang fault depression also had undergone two episodes of uplift during 30-27.8 Ma and 22.6-11.1 Ma. Moreover, the average apparent exhumation rates for the Chaluhe fault depression and Luxiang fault depression, could be calculated to be 70.34 and 60.33 m/Ma since 21.8 Ma and 18.9 Ma, respectively. The results of thermochronological analysis can also be supported by the evidence from geological relationships such as geodynamics, volcanic activity, and stratigraphic division and correlation.

Pressure Evolution and Hydrocarbon Migration-Accumulation in the Moliqing Fault Depression,Yitong Basin,Northeast China

The Yitong（伊通） basin is a Late Mesozoic and Cenozoic continental sedimentary basin in Northeast China.On the basis of well tests and seismic data,we use the 2D modeling technique to rebuild the pressure evolution and hydrocarbon migration in the Moliqing（莫里青） fault depression of the Yitong basin.Based on the modeling results,four conclusions are drawn as follows.（1） The Eocene Shuangyang（双阳） Formation within the Moliqing fault depression had entirely undergone three epi-sodic cycles of pressure accumulation and release in geological history,and the three tectonic move-ments since the Middle Eocene played important roles in the episodic changes of excess pressure.（2） The present formation pressure distribution is characterized by normal pressure in almost the entire fault depression with some residual overpressure.The differential distribution of pressure results mainly from the difference in rock facies,sedimentation rate,hydrocarbon generation,and fault activi-ties.（3） The hydrocarbon migration is more active during the release of pressure in the Moliqing fault depression,which happened mainly in the Middle-Late Oligocene and provided the driving force for hydrocarbon migration.（4） The hydrocarbon migration was mostly directed to the Shuangyang For-mation within the Jianshan（尖山） uplift and the Kaoshan（靠山） sag.With the superior condition ofhydrocarbon accumulation and the higher de-gree of hydrocarbon concentration,the north-west part of Kaoshan sag is considered a favor-able area for oil and gas exploration in the Moliqing fault depression.

Depositional Model and Tectonic Evolution of Tertiary Transform-Extensional Basins in Northeast China: Case Study on Yitong and Damintun Grabens

? The formation and evolution of the Tertiary transformextensional basins in Northeast China are controlled by extensional and strikeslidding combinational processes because the giant strikeslip fault system, TanchengLujiang fault, cut through the basement or margin. Two kinds of structural styles have been identified in Northeast China: Yitong and Damintun styles. The former shows a clear asymmetry, in which sediments came mainly from two lateral sides and thick filling sediments were adjacent to the main strikeslip fault. The latter shows symmetry filling, in which sediments came from the long axial ends in addition to from two lateral sides. The tectonic evolution of Tertiary transformextensional basins in Northeast China underwent three stages: Eocene extensional, Oligocene transformextensional and Neogene transpressional stages.

One Dimensional Evolution Modeling of Source Rocks in the Chaluhe Basin, Yitong Graben

Chaluhe Basin is in Jilin Province of China with a cumulative sedimentary rock thickness of about 6000 meters and has four subdivisions: Wanchang Structural High, Bo-Tai Sag, Xinanpu Sag, Liangjia Structure High and the Gudian Slope. The basin with its better source rock distribution and more favorable maturation indicators than the adjacent Moliqing and Luxiang Basins is expected to be a potential hydrocarbon-producing basin. Four (4) wells were used in determining the maturation hydrocarbon generating potential of the mudstone beds present in the Eocene Formations (Shuangyang, Sheling and Yongji). Obtained result revealed heat flow average of 71.8 mW/m2, oil generation between 3.15 mg/g TOC and 39.49 mg/g TOC with gas generation of 6.98 mg/g TOC to 92.83 mg/g TOC. In conclusion the Eocene Shuangyang mudstone is the main petroleum source rock.

Two Dimensional Evolution Modeling of Source Rocks in the Chaluhe Basin, Yitong Graben

Yitong Graben in Jilin Province of China, hosts three basins, namely: Chaluhe, Luxiang and Moliqing basins. The Chaluhe basin, as the focal point of this study has five subdivisions, thus, Bo-Tai sag, Wanchang Structural high, Liangjia Structure high Xinanpu sag, and the Gudian slope, with a cumulative sedimentary rock thickness of about 6000 metres. The basin is supposed to be a potential hydrocarbon-producing basin with its better source rock distribution and more favorable maturation indicators than the adjacent Luxiang and Moliqing Basin. Determining whether the mudstone beds present in the Eocene Formations are matured enough to generate hydrocarbons, three (3) wells with Seismic Lines (clh02, clh05 and clh07) were used for the study. It is observed that the entire region from NW to SE in the source rocks is mature to produce oil and gas. At depths of about 2400 m and below show good maturity with vitrinite reflectance values averaging 1.02% Ro. The Eocene Shuangyang mudstone is the main petroleum source rock.

Modeling of Source Rocks in Moliqing Basin of Yitong Graben, Northeast China

Moliqing basin is a continental sedimentary basin in the northeast of China, between Changchun and Jilin. The source rocks characterization was done using the data of three wells to define the generative potential, kerogen type and thermal maturity. Basin Mod software was used for the models. The three Eocene source rock formations in the basin are Shuangyang, Sheling and Yongji. Shuangyang is the most important due to its quantity and maturity levels of kerogen with very good generative potential (TOC between 2% - 4%) towards the southern region of the basin. According to the Tmax values, all three source rocks reached the mature stage, and the levels increased from early mature for the Yongji formation, to late mature for some locations of the Shuangyang formation. The 1D and 2D modeling reconstructed shows that the heat flow developed in the basin laid between 64 and 78.1 mW/m2 and had maximum heat flow location towards the center of the basin.

依兰‒伊通断裂带晚中生代走滑与伸展构造变形及其应力场

NE走向、延伸超过900km的依兰‒伊通断裂带是中国东北地区重要的大型断裂构造。然而关于该断裂带起源型式、伸展变形特征以及初始断陷时间长期以来存在较大分歧。本文对依兰‒伊通断裂带起源期和伸展构造变形规律、变形时间以及应力场特征进行了详细的野外调查、火山岩锆石U-Pb定年以及断层擦痕位移矢量反演研究。结果表明,依兰‒伊通断裂带在尚志隆起以及白垩纪‒古近纪地堑外侧保存着左行走滑断层或韧性剪切带,代表了其起源期构造。根据前人研究成果及未变形火山岩的年龄(125 Ma),限定起源时间为晚侏罗世初‒早白垩世初。早白垩世中期之前依兰‒伊通断裂带转变为伸展变形,南段控制发育的叶赫地堑具有典型的断陷盆地特征。在出露的花岗岩基底及地堑内下白垩统均可见一期NE走向正断层发育。应力场反演结果表明,依兰‒伊通断裂带起源期左行走滑活动是在近S-N向(偏NNW向)的挤压应力场作用下发育,晚期又叠加了NW-SE向的拉张应力场作用,导致该断裂带转为正断活动。本文认为太平洋区伊泽奈崎板块早白垩世初向东亚大陆下平板俯冲,随后俯冲板片后撤导致强烈的弧后伸展,是依兰‒伊通断裂带晚中生代左行走滑与伸展活动的动力学成因。

伊通盆地岔路河断陷古近系断层的垂向封闭性及其控藏作用

根据测录井、试油等资料,利用断面正压力法对伊通盆地岔路河断陷古近系控藏断层的垂向封闭性进行了研究。研究结果表明:(1)通过油气藏的埋藏深度、上覆地层平均密度、断层倾角等数据可计算出油气藏的现今断面正压力。伊通盆地岔路河断陷古近系油气藏的现今断面正压力值为13.3~56.0 MPa,成藏期断面正压力值为3.8~13.1 MPa,表现为“古开启-今封闭”的特征,因断层面所受压力越大,断层越紧闭,从而形成垂向封闭,反之则开启。(2)将研究区已知油气藏现今断面正压力值的最小值13.3 MPa定义为岔路河断陷垂向封闭的临界值,并进一步确定了控藏断层现今临界埋藏深度为2262 m。(3)断面正压力与断层紧闭指数呈正相关关系,控藏断层的垂向封闭临界压力值、临界埋藏深度和断层紧闭指数等参数可定量评价研究区控藏断层封闭性。(4)断层既可作为油气运移通道,又可为油气藏的形成提供遮挡作用。岔路河断陷西北缘C43油气藏的控藏断层在成藏期表现为垂向开启,与油气大量生排烃时期相吻合,具有沟通油源、运移油气的作用;C43—C48井区的控藏断层现今处于垂向封闭状态,可有效封堵油气。

吉林省五种鸟类分布新纪录

2018—2022年,在吉林省长春市伊通河流域进行鸟类资源调查,记录到欧亚鸲(Erithacus rubecula;43°52’34.76″N,125°21’52.74″E)、灰蓝山雀(Cyanistes cyanus;43°52’33.61″N,125°21’53.08″E;43°49’18.99″N,125°21’19.65″E)、三趾鸥(Rissa tridactyla;43°48’44.02″N,125°20’56.08″E)、中白鹭(Ardea intermedia;43°57’46.09″N,125°22’5.71″E)和赤嘴潜鸭(Nettarufina;43°58’2.72″N,125°22’4.42″E;43°48’27.18″N,125°20’49.41″E)5种鸟类,并拍摄到野外照片。经查阅相关文献确认为吉林省鸟类分布新纪录。

伊通盆地断裂体系特征及其演化历史

综合利用最新的地震、航磁、钻井等资料,对伊通盆地断裂体系进行了重新认识,并对断裂演化及其油气成藏的控制作用进行了综合分析。伊通盆地主要是受西北缘走滑断裂控制的新生代走滑-伸展盆地;断裂的性质、特征及演化极其复杂,按断裂特征及规模可划分为3个级别。一级断裂为西北缘和东南缘控盆边界断裂;二级断裂为早期张扭作用形成的呈雁列展布的马鞍山断裂,2号、3号、4号断裂和晚期压扭作用形成的西北缘逆冲断裂;三级断裂为盆地演化过程中形成的众多次级断裂。伊通盆地断裂演化特征与太平洋板块的俯冲作用、印度板块和欧亚大陆碰撞作用以及盆缘大黑山地垒和那丹哈达岭地体挤压位置与隆升强度密切相关,断裂演化经历了古近纪成盆期的右旋张扭作用阶段和新近纪反转期的右旋压扭及基底隆升作用阶段;新近纪反转期压扭作用形成的西北缘断褶带具有良好的油气勘探潜力。

伊通盆地含油气系统与油气藏

伊通盆地可以划分出莫里青-鹿乡断陷E2s、E2sh含油气系统和岔路河断陷E2s、E2sh含油气系统2个含油气系统及岔路河断陷E2s、E2sh、E2y-E3w复合含油气系统;在分析含油气系统形成的条件及含油气系统内油气富集带、油气藏的分布特征基础上,结合前人的研究成果,提出下步勘探方向。

吉林伊通盆地莫里青断陷古近系双阳组储层成岩作用研究

古近系双阳组是在吉林省伊通盆地莫里青断陷中油气赋存的主要层位。储层主要为湖底扇和扇三角洲的砂体。依据双阳组储层的大量薄片、扫描电镜、粘土矿物分析资料研究了该储层的成岩作用。研究结果表明双阳组储层的成岩作用经历了压实、压溶、胶结、交代和溶解5方面的作用。储层中自生粘土矿物蒙皂石向伊利石转化的过程可划分为蒙皂石渐变带、第1迅速转化带和第2迅速转化带,相应的成岩作用阶段可划分为早成岩阶段B期、晚成岩阶段A1期和晚成岩阶段A2期。依据在垂向上的成岩变化,建立了莫里青断陷双阳组储层的成岩作用演化序列。在垂向上成岩作用的类型和强度均存在明显的差异,造成了储层物性的垂向分带。

伊通盆地新近纪差异构造反转与油气成藏

结合最新的地震、钻井等资料，系统研究伊通盆地新近纪反转构造的差异改造特征、成因演化、变形规律及动力学背景，分析差异构造反转与油气成藏的关系。伊通盆地西北缘反转构造以右旋走滑冲断为主，可划分为高隆翻转冲断型、中隆斜列冲断型和低隆破裂冲断型，形成沿盆地西北缘平行展布的宽约2～4km的断褶带，油气成藏条件良好；而在盆地东南缘，反转构造则以相对较弱的右旋压扭和隆升掀斜为主，且在尖山、万昌、搜登等构造带顶部还发育了拱张性断裂，对早期油气藏起破坏作用。反转构造成因主要为太平洋板块向西俯冲产生弧后扩张而使中国东北大陆遭受挤压隆升，同时还受印度板块与欧亚板块碰撞所产生的远程挤压效应影响，此外还与盆缘隆起的发育位置和隆升强度密切相关。

伊通盆地岔路河断陷重力流沉积特征及油气勘探意义

伊通盆地岔路河断陷始新统中发育大量水下重力流沉积,根据重力流发育位置及沉积特征,可划分为浅水浊流沉积、深水浊流沉积、水下滑塌沉积和水下泥石流沉积4种类型。通过对本区区域地质背景、钻井岩性、测井和地震等资料的综合研究,认为水下滑塌和水下泥石流沉积为再搬运和再沉积作用的产物,常与断裂相伴生;但浅水及深水浊流沉积常发育在前扇三角洲部位,大部分是由阵发性水下分流河道水流事件形成的,部分属于滑塌浊流二次沉积成因。油气勘探成果表明,研究区水下浊积砂体的储集物性普遍较好,并已有油气勘探突破,证实位于二号断层下降盘的梁家构造带和万昌构造带周缘的深水浊积砂体和浅水浊积砂体有着良好的油气勘探前景。

伊通盆地新近纪以来的反转构造特征

郯庐断裂带于新近纪以来呈现强烈的挤压和逆冲活动,使伊通盆地相应地遭受了挤压而反转,盆地西北缘和东南缘地层被强烈抬升和剥蚀并形成逆冲断层、断褶带及断隆带等一系列反转构造。反转构造在盆地西北缘和东南缘具有显著差异性：在盆地西北缘形成宽2-4km的断褶带,该带可能是一个新的油气勘探领域,具备良好成藏条件,油气勘探重点应在褶皱带浅层和逆冲断层下盘;在盆地东南缘尖山和万昌等构造带则形成拱张性断隆带,对早期形成的油气藏起破坏作用,应该寻找深层和构造带斜坡部位的油气藏。反转构造的成因主要为太平洋板块向西俯冲产生的弧后扩张作用及印度洋板块向欧亚板块碰撞的远程挤压作用,还与盆缘刚性块体隆升及侧向挤压作用有关,盆缘刚性块体的分布位置及隆升强度对盆地反转构造的平面展布特征及反转强度具有重要影响。

伊通盆地莫里青断陷双阳组湖泊水下扇沉积特征

本文详细研究了伊通盆地莫里青断陷双阳组沉积类型,并将该区湖泊水下扇的岩相组成划分为5种类型:经典浊积岩相、块状砂岩相、砾质砂岩相、颗粒支撑砾岩相、基质支撑砾岩相;将湖泊水下扇划分为内扇、中扇、外扇三个亚相,对各亚相进一步划分了若干微相。湖泊水下扇沉积为该区地层的主要沉积特征,在垂向上具有进积型和退积型两种类型。

狭长走滑断陷盆地构造对沉积—成藏的控制作用——以伊通盆地为例

伊通盆地为郯庐断裂带北延至吉林省境内的狭长新生代断陷盆地,受郯庐断裂带构造域以及西太平洋板块构造域的共同影响,盆地经历了早期斜向伸展、中期持续走滑和后期构造反转的复杂构造演化历程,对油气成藏过程产生重要控制作用。通过分析伊通盆地构造样式、盆地演化过程,研究了构造对沉积、成藏的控制作用,揭示狭长走滑断陷盆地早期伸展走滑为烃源岩和储层的发育提供了良好条件,晚期构造挤压和反转有利于油气藏的形成。

郯庐断裂带伊通段新生代构造演化特征及其控盆机制

郯庐断裂带伊通段的构造活动对伊通盆地的形成与油气分布具有重要控制作用。通过对最新的地震、钻井、物探、露头等资料分析,认为郯庐断裂带伊通段新生代以来的构造演化可划分为三个阶段,即:古新世-始新世中期的左旋走滑挤压阶段、始新世中期-渐新世末期的右旋走滑伸展阶段和中新世-第四纪的右旋走滑和隆升阶段。其中第二阶段为主成盆期,控盆断裂活动特征具有南早北晚、由南向北迁移的规律,盆地沉积中心因此也从南西向北东迁移并靠近西北缘主断裂;第三阶段为盆地反转期,控盆断裂发生右行压扭和隆升,盆地东南缘发生拱张使得万昌构造带等早期形成的构造高部位油气藏遭受破坏,而盆地西北缘受侧向挤压则形成宽2～4km的西北缘断褶带,具有良好油气成藏条件和勘探潜力,是盆地新的找油领域。

伊通盆地鹿乡断陷双阳组储层孔隙结构特征及其控制因素

通过对钻井岩芯及铸体薄片、扫描电镜观察,结合压汞分析测试,研究了伊通盆地鹿乡断陷双阳组储层的孔隙结构特征。结果表明:储层成因类型主要为扇三角洲砂体,部分为水下扇砂体;储层砂体孔隙类型以次生溶蚀孔隙为主,部分为原生粒间孔隙,具体可见粒内溶孔、原生粒间孔和粒间溶蚀扩大孔等;孔隙喉道较小,分选不好,连通性差,总体为低孔低渗型储层,其中,双阳组二段储层略好于双三段,双一段最差。双阳组储层孔隙结构特征主要受砂体成因类型和成岩作用的控制,此外,岩石粒度和构造作用也对孔隙结构有一定的控制作用。