江西新余早侏罗世地层中发现鹦鹉螺化石

江西新余早侏罗世地层中发现鹦鹉螺化石刘继钦（江西煤田地质局二二四队分宜３３６６００）江西新余花鼓山矿区门口山向斜由下侏罗统至上三叠统地层组成。我们在该向斜找煤勘探时，有部分钻孔穿过该地层，在下侏罗统与上三叠统连续沉积的这段海相地层中发现了大量的双壳类...     

福建晚三叠世－中侏罗世地层划分

福建晚三叠世－中侏罗世地层以陆相盆地沉积为主，仅闽西南局部有海陆交互相沉积。地层分区大致以政和－大埔断裂为界，分为闽西地层小区和闽东地层小区。根据各盆地地层序列及岩石组合特征，岩石地层单位可划分为陆相沉积的大坑村组、文宾山组、焦坑组、梨山组及漳平组和以海陆交互相沉积的象牙群，包括下村组和藩坑组。其中大坑村组相当于年代地层单位的上三叠统卡尼－诺利阶，文宾山组、焦坑组相当于诺利阶上部－瑞替克阶，梨山组相当于下侏罗统赫塘－托尔阶，漳平组相当于中侏罗统巴柔－卡洛阶中下部，下村组相当于下侏罗统赫塘－辛涅缪尔阶，藩坑组相当于辛涅缪尔－托尔阶。此外，文中还论述了各门类生物群的组合特征及其分布范围。     

四川盆地西部坳陷晚三叠—早白垩世地层沉积相

对四川盆地西部坳陷区内晚三叠—早白垩世地层、沉积相提出了一些新的认识 ,认为南部存在中侏罗统千佛崖组 ,中南部有较多的三角洲相沉积 ;讨论了沉积相的时空展布规律 ,这对区内上三叠—下白垩统沉积—层控矿产的研究和油气资源勘探均有重要的作用     

湖北省主要煤系成煤环境及找煤方向浅析

湖北省主要煤系地层是下二叠统“梁山煤系”、上二叠统“龙潭煤系”和上三叠统-下侏罗统“香溪煤系”。“粱山煤系”和“龙潭煤系”主要分布在鄂东南、鄂西南地区,“香溪煤系”零星分布在鄂州-赤壁、远安-当阳、巴东-兴山、利川等地。研究认为：二叠纪成煤环境属近海型,而晚三叠世、早侏罗世属于内陆型。控制聚煤作用的主要因素有：①成煤环境为滨岸沼泽相区,沼泽发育之前沉积物若为砂质、粉砂质岩类,则含煤性好,反之若为泥质或粘土质岩类,则含煤性差;（爹煤系沉积的早期沉积基底剥蚀夷平为坳陷地带,到中晚期坳陷逐渐增大,能形成宽阔的聚煤（盆地）带;⑧地壳沉降幅度大,升降速度乎稳,泥炭沼泽发育时间长;④地壳振荡次数频繁,沉积旋回多,煤层厚度较大,含煤性好,反之．沉积旋回少或不完整,煤层少,且薄,含煤性差。通过分析有利的聚煤因素,提出了各煤系的找煤方向。     

营山地区上三叠统与中、下侏罗统油气源特征对比研究

从烃源岩特征、天然气组分、油气碳同位素、凝析油全烃和轻烃、储层沥青等方面对营山地区上三叠统和中、下侏罗统油气源特征进行了对比研究,阐明了营山地区上三叠统须家河组和中、下侏罗统油气的地球化学特征、成因和可能来源。研究表明营山地区上三叠统须家河组油气主要来自须家河组自身的煤系烃源岩,天然气以成熟腐殖型母质成因为主,而中、下侏罗统气藏产出的油气主要来自其自身的烃源岩。营山地区构造活动强烈,断层发育,使得部分井区中、下侏罗统产出的天然气特征与下伏产层极为相似,反映了断层对该井区附近的各层段有一定的沟通作用。中、下侏罗统地层在部分井区可能有上三叠统须家河组油气的侵入,须家河组烃源岩对中、下侏罗统油气成藏有一定贡献作用。     

滇中鱼坝村组的建立及陆相侏罗系底界

滇中及相邻地区上三叠统舍资组含煤层与下侏罗统冯家河组红层之间，连续沉积了一套杂色细碎屑岩过渡层。其分布稳定，该层所含化石及磁性地层特征表明其时代属早侏罗世。因此建立下侏罗统鱼坝村组，并确定该组底界为陆相侏罗系的底界。     

西藏措勤盆地的地层学研究进展及上二叠统—侏罗系地层序列的厘定

本文简要总结了西藏措勤盆地相关区域的地层学研究进展。近年来,笔者及研究团队对措勤盆地及邻区进行了多次野外地质调查和室内古生物鉴定和研究,获得了一些新的发现和认识,在结合前人在相关地区取得的地层学成果和资料的基础上,厘定了该地区上二叠统—侏罗系的地层序列。措勤盆地的上二叠统是以文布当桑组为代表的灰岩和以木纠错组为代表的白云岩。三叠系存在着广海陆棚相和碳酸盐岩台地两种地层序列:前者自下而上划分为下三叠统嘎仁错组、中三叠统至上三叠统卡尼阶珠龙组、上三叠统诺利阶江让组、上三叠统瑞替阶至下侏罗统敌布错组;后者自下而上划分为木纠错组、待建的中三叠统、上三叠统诺利阶麦隆岗组和上三叠统瑞替阶至下侏罗统的确哈拉组。下侏罗统与上三叠统瑞替阶难以区分开。中侏罗统的岩性为深海-半深海相泥岩夹有基性-超基性岩。上侏罗统自下而上划分为萨波直不勒组和吐卡日组,目前尚未发现提唐阶的化石,因此推测下白垩统多尼组和吐卡日组之间有沉积间断。措勤盆地在晚二叠世—早三叠世、晚三叠世诺利期和晚侏罗世牛津期—基默里奇期都处于碳酸盐岩台地环境,冈底斯地区在中三叠世和中侏罗世发生了2期构造伸展事件,在晚三叠世诺利期末期和晚侏罗世基默里奇期晚期发生了两次构造抬升事件。构造伸展和挤压抬升造成了海平面的反复升降变化,导致了深水和浅水沉积相的垂向叠置,为油气成藏创造了良好的沉积建造组合条件。上二叠统—侏罗系地层序列还有待于进一步完善,应该加大地层古生物学的投入力度。     

和什托洛盖盆地中侏罗统西山窑组层序地层及聚煤规律分析

和什托洛盖盆地中侏罗统西山窑组发育多套煤层。据钻井岩心和测井曲线资料,研究和什托洛盖盆地中侏罗统西山窑组层序地层格架及沉积体系空间展布特征,在此基础上分析煤的聚集规律。研究区主要发育辫状河、三角洲和湖泊3种沉积体系,物源来自盆地南北方向。西山窑组可划分为两个三级层序,煤层主要分布于三级层序的湖扩和高位体系域,高位体系域中晚期为泥炭沼泽发育的最佳时期。     

浅议西藏区域地层区划及其含煤地层

据西藏自治区大地构造演化特征,从整个青藏高原构造单元分布特点考虑,本文将西藏自治区地层区划结合构造单元和含煤地层一并考虑,将其划分为三个构造-地层大区:羌塘-三江构造-地层大区、班公湖-双湖-怒江构造-地层大区、冈底斯-喜马拉雅构造-地层大区。从区域地层、沉积构造及其古生物化石组合等特点综合分析,得出西藏赋煤区聚煤作用具有时代多、分布广、煤层层数多、厚度薄和稳定性差的总体特点。区内含煤地层包括下石炭统、上二叠统、上三叠统、中侏罗统、下白垩统和古近系等。最主要煤系是下石炭统马查拉煤系、上二叠统妥坝煤系、上三叠统土门煤系、下白垩统多尼煤系。     

西藏措勤盆地的上古生界-下中生界：潜在的油气沉积建造

新的地层和古生物学研究结果表明,措勤盆地在晚古生代一早中生代不存在长达75Ma以上的沉积间断．其中,晚二叠世-晚三叠世诺利期都是海相碳酸盐岩地层,晚三叠世瑞替期-早中侏罗世为陆缘碎屑岩地层．两者之间为角度不整合接触．措勤盆地在晚二叠世-晚三叠世诺利期一直处于海相碳酸盐岩盆地中．晚三叠世瑞替期-早中侏罗世仍然是接受巨厚沉积的低洼地区。从宏观的油气勘探的战略评价角度看．措勤盆地在中二叠世栖霞期-晚三叠世诺利期的海相碳酸盐岩地层具有生油层的性质,上三叠统瑞替阶-中下侏罗统具有盖层的性质,两者之间的角度不整合具有储集层的性质。措勤盆地中二叠统-下侏罗统构成一个油气的有利勘探层系．称为古格层系。     

川西前陆盆地中侏罗统千佛岩组沉积体系研究

千佛岩组发育冲积扇、曲流河、三角洲和湖泊沉积。曲流河发育洪泛平原和河道两个亚相;三角洲发育三角洲前缘、三角洲平原及前三角洲三个亚相;湖泊相则发育浅湖和滨湖亚相;冲积扇分出扇中和扇端两个亚相。龙门山系周期性推覆构造活动是川西前陆盆地沉积作用及层序发育的主控因素。     

山西寿阳—阳泉地区石炭—二叠系沉积环境及其沉积特征

本区石炭—二叠系是在海湾背景下发育的一套由滨海平原—三角洲平原—冲积平原沉积组成的海退层系。主要沉积环境是三角洲平原,其上部为冲积平原包括网状河和辫状河;下部为海湾（或分支间湾）、潮下碳酸盐岩、潮间介壳滩、碎屑岩潮坪及滨海沼泽湿地等。三角洲为河控浅水三角洲。上述沉积环境,随海水退却在时空上具明显的规律性变化。     

Sedimentology of Fraser River delta peat deposits: A modern analogue for some deltaic coals

On the Recent lobe of the Fraser River delta peat accumulation has actively occurred on the distal lower dilta plain, the transition between upper and lower delta plains, and the alluvial plain.Distal lower delta plain peats developed from widespread salt and brackish marshes and were not influenced appreciably by fluvial activity. Lateral development of the marsh facies were controlled by compaction and eustatic sea level rise. The resulting thin, discontinuous peat network contains numerous silty clay partings and high concentrations of sulphur. Freshwater marsh facies formed but were later in part eroded and altered by transgressing marine waters. The peats overlie a thin, fluvial, fining-upward sequence which in turn overlies a thick, coarsening-upward, prodelta—delta front succession.Lower delta plain—upper delta plain peats initially developed from interdistributary brackish marshes and were later fluvially influenced as the delta prograded. The thickest peats occur in areas where distributary channels were abandoned earliest. Sphagnum biofacies replace sedge-grass-dominated communities except along active channel margins, where the sedge-grass facies is intercalated with overbank and splay deposits. The peats are underlain by a relatively thin sequence of fluvial deposits which in turn is underlain by a major coarsening-upward delta front and pro-delta sequence.Alluvial plain peats accumulated in back swamp environments of the flood plain. Earliest sedge-clay and gyttjae peats developed over thin fining-upward fluvial cycles or are interlaminated with fine-grained flood deposits. Thickest accumulations occur where peat fills small avulsed flood channels. Overlying sedge-grass and Sphagnum biofacies are horizontally stratified and commonly have sharp boundaries with fine-grained flood sediments. At active channel margins however, sedge-grass peats are intercalated with natural levee deposits consisting of silty clay. These levees reduce both the number and size of crevasse splay deposits.Coal originating from peats of the different environments of the Fraser delta would vary markedly in character. Peats of the lower delta plain will form thin lenticular coal seams with numerous splits and have a high ash and sulphur content. Peats from the lower to upper delta plain will be laterally extensive and of variable thickness and quality. Basal portions of the seams will contain numerous splits and have a high sulphur content whereas upper portions will be of higher quality. Peats from the upper delta plain—alluvial plain will form thick, isolated and laterally restricted coal seams characterized by low ash and sulphur contents.     

我国冲积平原区洪水事件重建研究进展及展望

冲积平原作为城市聚集和人类发展的重要区域,长期面临着巨大的洪水灾害风险,基于平原区丰富的沉积记录开展洪水事件重建研究有助于科学认识洪水历史及规律,具有重要的意义和价值.通过系统梳理国内外在冲积平原洪水重建研究中的最新进展,重点回顾了近年来我国长江中下游平原和华北平原相关代表性成果,分析了平原区洪水沉积主要特征和识别标志,归纳了特大洪水事件的典型沉积序列和主要沉积环境.最后,结合国内外研究热点和前沿,展望了未来我国冲积平原在洪水重建研究的巨大潜力,建议以沉积相和地层关系为基础,进一步扩展洪水重建研究的时空范围,探索从定性到定量获取不同规模洪水的水文信息,进而开展流域尺度的综合分析,深入了解洪水的驱动机制和影响因素.      

滇东田坝黔西土城晚二叠世煤系上段沉积相及含煤性

晚二叠世煤系上段相当于长兴阶,是浅水三角洲复合体破坏阶段沉积。本区可分为上三角洲平原、上下三角洲过渡带、下三角洲平原三大相区及发育在三角洲体系外侧的坝湾体系。西部以河流作用为主,东部具河流和潮汐作用双重特征。形成于上下三角洲过渡带的煤层最具工业价值,其次是上三角洲平原,其它沉积类型的煤层一般不具工业价值。     

成煤环境的演替及其对盆地构造活动性的响应──以塞文盆地为例

本文以法国中央高原斯蒂芬期（Ｃ３）塞文（Ｃｅｖｅｎｎｅｓ）断陷聚煤盆地为例，据其不同阶段岩相古地理展布特征与早期构造在空间上的配置关系，指出了成煤环境在时间上的演替这一动态过程与盆地的构造活动性之间的内在联系。     

西北内陆盆地的红层类型与砂岩型铀矿

本文在调研我国西北内陆盆地中的红层与砂岩型铀矿关系的基础上,提出了一个以沉积相和红化成因为基础的红层分类:把内陆盆地中的红层分为陆解阶段形成的冲积平原红层和浅湖红层;成岩后生阶段形成的河流冲积红层、三角洲红层和沙漠红层;以及表生风化阶段形成的溅泼红(次生红层)等6类红层。并依据这6类红层的特征、产出构造环境,以及含矿主岩到各类红层的Eh、pH、Th/U、Fc~(3+)/Fc~(2+)、Sr/Ba等地化特征值的变化,确定了它们与砂岩型铀矿的关系,即陆解阶段岩石红化时为开放环境,活性铀易于流失,对成矿不利;而成岩后生阶段,岩石红化时的环境为封闭系统,对成矿有利,能形成铀矿床。     

试论我国东北部中、新生代陆相含煤地层沉积序列模式

我国东北部中、新生代陆相含煤地层的中部为厚层泥岩,其上、下均含有煤层,顶底为粗碎屑岩。可据此规律探找新含煤层位和含煤地层的划分和对比。     

大型复杂松散堆积体形成机制的内外动力耦合作用初 探

在我国西部山区广泛发育和分布第四纪大型复杂松散堆积体,这是一套介于土、岩之间的过渡类型的地质体;其成因复杂,主要包括残坡积物、崩滑堆积体、冲洪积物、冰碛物和冰水沉积物等两种或多种组合混杂堆积,明显区别于东部平原区的单一成因类型。本文通过资料对比分析,对大型复杂松散堆积体的一般特征、主要类型和区域分布规律进行了系统总结,最后从耦合的角度来探讨其成因机制,并提出河谷型松散堆积体的内外动力耦合概念模型,研究认为大型复杂松散堆积体属于典型的内外动力耦合作用产生的多期次、成因复杂的复合地质体。     

Holocene alluvial stratigraphy in the upper Susquehanna River Basin, New York

Two alluvial terraces and the present flood plain were studied at two locations along the Susquehanna and Unadilla Rivers in south-central New York state. They have formed since deglaciation and incision of the stream channels into the valley train deposits. The higher terrace has noncumulative soil profiles with well-developed color B horizons predominantly of silt loam and very fine sandy loam. The terrace is weathered to a degree similar to nearby glacial outwash terraces that have caps of similarly textured sediments. Incision that produced the terrace occurred before 9705 ± 130 yr B.P. The lower terrace is characterized by relatively thick, vertical-accretion deposits of silt loam that contain sequences of thin, buried A, color B, and C horizons. They were formed between about 3240 ± 110 (¹⁴C data of soil humin) and 235 ± 80 yr B.P. Deposits above the 235 ± 80 yr B.P. stratum are unweathered. The soil stratigraphy and ¹⁴C dates of soil humin from buried A horizons are surprisingly well correlated between sites. Most sediments of the present flood plain have been deposited since 1120 ± 80 yr B.P. Incipient A horizons and oxidation of inherited organic matter in the subsoil are the only evidence of pedogenesis in the flood-plain deposits that are older than 275 ± 80 yr B.P. The most recent flood-plain fill deposited since then is unaltered. These youngest sediments of the flood plain along with the youngest veneer of vertical-accretion deposits on the lowest terrace are associated with an increased rate of deposition largely attributable to clearing of the forests by settlers, beginning in the late 1700s. Comparison of the alluvial stratigraphy with the radiocarbon-dated pollen stratigraphy of southwestern New York (Miller 1973) reveals some apparent time correlations between alluvial events and vegetation changes. This gives reason to speculate that climatic change or forest catastrophes such as disease or drought are causes of some of the alluvial events.