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1.
花东盆地晚中新世以来沉积演化特征 总被引：1，自引：0，他引：1
利用近年来在台湾东部海域采集的多道地震和多波速测深资料，对该海域花东海盆区晚中新世以来的沉积充填演化特征进行描述和分析。通过对花东海盆区域地形特征描述、层序地层格架的建立和地震剖面的解译，在本区晚中新世以来的沉积充填中刻画出6种典型地震相类型，并分析其对应的沉积相类型，包括浊积扇、浊积水道充填、块体流、沉积物波、海底峡谷－伴生沉积物滑塌变形－充填、深水扇沉积。结合地震相平面分布及垂向沉积相叠置关系，将晚中新世－第四纪沉积充填演化划分为3个阶段:晚中新世晚期开始受到块体流冲蚀阶段，到海底峡谷冲刷－沉积物失稳－峡谷充填－再侵蚀阶段，到峡谷输送的大量沉积物在上新世以来主要堆积发育了沉积物波、浊积扇、深水扇等沉积体系阶段。 相似文献
2.
Michele Rebesco Robert D. Larter Angelo Camerlenghi Peter F. Barker 《Geo-Marine Letters》1996,16(2):65-75
Multichannel seismic reflection profiles from the continental rise west of the Antarctic Peninsula between 63° and 69°S show the growth of eight very large mound-shaped sedimentary bodies. MCS profiles and long-range side-scan sonar (GLORIA) images show the sea floor between mounds is traversed by channels originating in a dendritic pattern near the base of the continental slope. The mounds are interpreted as sediment drifts, constructed mainly from the fine-grained components of turbidity currents originating on the continental slope, entrained in a nepheloid layer within the ambient southwesterly bottom currents and redeposited downcurrent. 相似文献
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The Bohai Bay Basin is a classic non-marine rift basin in eastern China. The Paleogene Dongying sequences are the main hydrocarbon-bearing stratigraphic unit in the basin. Using three-dimensional (3-D) seismic data and one well control in the BZ3-1 Block in the western slope of the Bozhong Sag, we analyzed 3-D facies architectures of the Dongying sequences. The Dongying Formation, a second-order sequence, can be subdivided into four third-order sequences (from base to top: SQ1, SQ2, SQ3, and SQ4). The facies architecture was analyzed by using the seismic sedimentology approach based on 3-D seismic data. Sediment of the Dongying sequences was derived from the northern Shijiutuo Uplift via four major configurations of incised valleys, namely “V”, “U”, “W”, and composite shaped incised valleys. Seismic stratal slices reveal branching and converging characteristics of the channels from upstream to downstream. On the basis of an integrated analysis of well log, core data, seismic facies based on multi-seismic attributes, three sedimentary facies (e.g., “delta”, “fan-delta”, and “shore” or “shallow lacustrine” facies) have been recognized. The four types of incised valleys and their evolution control the sedimentary systems in the sedimentation area. The numbers and sizes of the fans are controlled by the sedimentary systems at various scales. Incised valley-fill and deltaic sand bodies are excellent hydrocarbon reservoirs and potentially good exploration targets for the study area. The reservoir quality of sequences SQ1, SQ2, and SQ3 become better gradually from base to top. The proposed sediment dispersal patterns may aid in the prediction of potential reservoir distribution. This study also demonstrates that facies architecture analysis using sequence stratigraphy and seismic sedimentology may serve as an effective approach for constructing 3D facies models for petroleum exploration in areas lacking of well or outcrop data. 相似文献
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A. A. Schreider E. L. Mazo A. A. Bulychev M. P. Kulikova D. A. Gilod Al. A. Schreider A. N. Boiko 《Oceanology》2010,50(6):961-970
An electronic databank including the results of seismic investigations and schemes of the sediment thickness’s distribution
patterns was built up for two seismostratigraphic complexes in the Falkland Basin. The interface’s border was dated, and the
sedimentation rates were estimated for each complex. An integrated map of the cumulative thickness of the deposits and sedimentation
rates was developed. The lowest limits of the parameters of the sedimentation process were characterized for the sedimentary
layers affected by compaction and erosion. 相似文献
6.
本文采用高分辨率单道浅地震剖面资料研究闽江口外海域的全新统沉积作用。研究区的全新统底面为MIS 2期侵蚀面，局部为古河道，深度一般在现海面下约30～60 m，最深约65 m；近岸浅，外海深，局部受古河道的下切影响呈条带状负地形。全新统由早全新世晚期以来的海相沉积层(U1)和早全新世河流湖沼相沉积层(U2)组成，前者包括滨浅海平行地震相和河口滨岸前积地震相，根据其反射波向陆上超和向海下超底界面，结合沉积物厚度分布特征，可以判断主要的沉积物来源和运移趋势。全新统沉积层厚度一般为10～20 m，最厚约38 m，位于古河道区，但是在马祖列岛和白犬列岛之间海区缺失。海相全新统沉积层的厚度为数米至20 m，最厚约25 m，位于研究区东南部(海坛岛东侧)。自全新世海侵以来，沉积物主要来源于3部分:台湾海峡来沙为研究区南部海区提供了沉积物；闽江悬沙扩散沉积物覆盖研究区北部海区，主要沿NE方向至外海，在河口向南呈舌状，现代沉积中心位于河口北部，厚度大于15 m；浙闽沿岸流来沙对研究区东北部海区的沉积物有影响。沉积环境划分为台湾海峡源沉积区、闽江源沉积区、东北部混合沉积区和马祖?白犬沉积缺失区，平均沉积速率分别约为0.8 mm/a、1.0 mm/a、1.1 mm/a和0 mm/a。马祖?白犬沉积缺失区主要因为沉积物受沿岛环流的控制。 相似文献
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The seismic stratigraphy, evolution and depositional framework of a sheared-passive margin, the Durban Basin, of South East Africa are described. Based on single-channel 2D seismic reflection data, six seismic units (A-F) are revealed, separated by major sequence boundaries. These are compared to well logs associated with the seismic data set. Internal seismic reflector geometries and sedimentology suggest a range of depositional regimes from syn-rift to upper slope and outer shelf. Nearshore and continental facies are not preserved, with episodic shelf and slope sedimentation related to periods of tectonic-induced base level fall. The sedimentary architecture shows a change from a structurally defined shelf (shearing phase), to shallow ramp and then terminal passive margin sedimentary shelf settings. Sedimentation occurred predominantly during normal regressive conditions with the basin dominated by the progradation of a constructional submarine delta (Tugela Cone) during sea-level lowstands (LST). The earlier phases of sedimentation are tectonic-controlled, however later stages appear to be linked to global eustatic changes. 相似文献
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A brief review of the published evidence of current deposits around Italy is the occasion to test the robustness of matching bottom current velocity models and seafloor morphologies to identify contourite drifts not yet documented. We present the result of the regional hydrodynamic model MARS3D in the Northern Tyrrhenian and Ligurian Sea with horizontal resolution of 1.2 km and 60 levels with focus on bottom current: data are integrated over summer and winter 2013 as representative of low and high intensity current conditions.The Eastern Ligurian margin is impacted by the Levantine Intermediate Water (LIW) with modeled mean velocity of bottom current up to 20 cm s−1 in winter 2013 and calculated bottom shear stress exceeding 0.2 N m−2 in water depth of 400–800 m. By crossing this information with seafloor morphology and geometry of seismic reflections, we identify a sediment drift formerly overlooked at ca 1000 m water depth. The Portofino separated mounded drift has a maximum thickness of at least 150 m and occurs in an area of mean current velocity minimum. Independent evidence to support the interpretation include bottom current modelling, seafloor morphology, seismic reflection geometry and sediment core facies. The adjacent areas impacted by stronger bottom currents present features likely resulted from bottom current erosion such as a marine terrace and elongated pockmarks.Compared to former interpretation of seafloor morphology in the study area, our results have an impact on the assessment of marine geohazards: submarine landslides offshore Portofino are small in size and coexist with sediment erosion and preferential accumulation features (sediment drifts) originated by current-dominated sedimentary processes. Furthermore, our results propel a more general discussion about contourite identification in the Italian seas and possible implications. 相似文献
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A digitally recorded and processed multichannel seismic profile between Cromer (England) and Sylt (Germany) has provided the first continuous section through the Miocene to Middle Pleistocene delta complex of the southern North Sea Basin. The profile depicts the progressive westward expansion of deltaic sedimentation that eventually filled in this gently subsiding epicontinental basin. Significant basinward shifts in seismic facies occur above all but one of 14 seismic sequence boundaries that punctuate the deposition of up to 830 m of deltaic sediments on the profile. These sequence boundaries and the morphology of prodelta, delta front, delta top and fluvio-deltaic seismic facies record the interaction between subsidence, cyclic fluctuation in sediment supply to, and cyclic change of relative sea level within the basin. Two submarine slides were developed within delta front facies in the Pliocene section and the profile has intersected a swarm of Elsterian (Middle Pleistocene) glacial palaeovalleys that have been incised into the upper part of the delta complex. 相似文献
10.
Seismic characteristics of sediment drifts: An example from the Agulhas Plateau,southwest Indian Ocean 总被引：3，自引：0，他引：3
Sediment drifts provide information on the palaeoceanographic development of a region. Additionally, they may represent hydrocarbon reservoirs. Because of this, sediment drift investigation has increased over the last few years. Nevertheless, a number of problems remain regarding the processes controlling their shape, the characteristic lithological and seismic patterns and the diagnostic criteria. As an example, sediment drifts from the Agulhas Plateau, southwest Indian Ocean, are presented here. They show a variety of seismic features and facies including an asymmetric mounded geometry, changes in internal reflection pattern, truncation of internal reflectors at the seafloor and discontinuities. This collection of observations in combination with the local oceanography appears to comprise a diagnostic tool for sediment drifts. 相似文献
11.
Eight seismic profiles from the southwestern Caspian Sea were analyzed to establish the sedimentary environments and depositional
history in the South Caspian Basin since Pliocene times. Based on reflection terminations, nine sequence boundaries (S1 to
S9) were identified and traced across the study area. Consequently, nine depositional sequences (S1–S9) were defined on the
basis of seismic facies analysis. The results suggest a transition from non-marine sedimentation in the Lower Pliocene to
marine-dominated conditions in the Upper Pliocene (S1–S4). Marine conditions then continued to the present time; however,
several sea-level changes led to the formation of sequences S5 to S9. Although no local sea-level curve is available due to
a lack of well data, there is good agreement between the seismic stratigraphy of the study area and a published regional sea-level
curve. 相似文献
12.
Elodie Marchès Thierry Mulder Michel Cremer Cédric Bonnel Vincent Hanquiez Eliane Gonthier Pascal Lecroart 《Marine Geology》2007,242(4):247-260
The margin of the Gulf of Cadiz is swept by the deep current formed by the Mediterranean Outflow Water (MOW) flowing from the Mediterranean to the Atlantic. On the northern margin of the Gulf (Algarve Margin, South Portugal), the MOW intensity is low and fine-grained contourite drifts are built up with an alongslope development. From new sedimentological data, this study emphasizes the presence of two types of contourite drifts separated only by a deep submarine canyon incising the slope with a north-south orientation (Portimão Canyon). High-resolution seismic and bathymetry interpretation shows that on the eastern side of the canyon, the MOW forms a thick and large detached drift (Albufeira Drift) prograding toward both north and west, as shown in seismic profiles, with a high sedimentation rate. On this side of the canyon, the MOW intensity is high enough to erode the slope forming a moat channel (Alvarez Cabral). On the western side of Portimão Canyon, the MOW energy is lower, preventing moat channel erosion. Only flat and thin drift develops (Portimão and Lagos Drifts) with slow aggradation and a low sedimentation rate. This difference in drift development is due to the presence of the canyon which generates an important change in hydrodynamic of the MOW, confirmed by temperature-density measurements showing that MOW flows down Portimão Canyon. The canyon is responsible for the deviation of the direction of the MOW as it partly catches the deep-sea current flowing westward (i.e. capture phenomenon). It creates, thus, a decrease of the flow energy, competency and capacity between the east and west sides of the canyon. Through this phenomenon of MOW deep-sea current capture, the canyon constitutes a morphologic feature generating an important change in the contourite deposition pattern.In addition to already known climatic and oceanographic influences, our results show the role of canyons on contourite drift building. This study provides new elements on autocyclic factors influencing the contourite sedimentation, which are important to consider in future sedimentary paleo-reconstruction interpretations. 相似文献
13.
地震多属性预测技术在南黄海二叠系至三叠系沉积分析中的应用 总被引：2，自引：0，他引：2
以往对南黄海盆地沉积相分析主要根据地震剖面的振幅、相位和频率进行地震相划分,再结合测井资料得到沉积相分布,而地震属性除了以上3种属性外,还包含着多种与沉积相有关的属性,以往对沉积相的分析未能充分利用这些地震属性信息.目前,南黄海盆地钻井资料较少,充分利用地震多属性信息对南黄海盆地三叠系下统青龙组—二叠系上统龙潭组、大隆... 相似文献
14.
位于马来盆地与西纳土纳盆地交汇处的研究区上新统?更新统发育复杂的浅海、海陆过渡相水下分支河道体系,常规的地震资料无法进行精细识别刻画。通过对叠后地震资料进行希尔伯特?黄变换,提取了地震资料高频分量,提高了地震资料的分辨率,有效识别了薄层砂泥岩交互特征和细微沉积体。通过对高频分量进行瞬时属性提取,明确了目的层段水下分支河道的平面展布特征。与常规叠后地震属性相比,经过希尔伯特?黄变换后的叠后地震资料提取的瞬时属性显示了更多沉积体系的细节特征,为水下分支河道的内部结构、发育期次、切割关系等时空演化研究提供了更高分辨率的地震数据。 相似文献
15.
台西南盆地地质构造特征及油气远景 总被引：7，自引：3，他引：7
杜德莉 《海洋地质与第四纪地质》1991,11(3):21-33
本文从盆地的基本地质特征入手,分析了台西南盆地的地层、沉积、构造特征及油气条件,在进行盆地的定性分析的基础上,对盆地内的次级构造单元进行了类比,对盆地的含油气远景进行了评价,提出了该盆地的油气勘探方向。 相似文献
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Boundary current-controlled turbidite deposition: A sedimentation model for the Southern Nares Abyssal Plain,Western North Atlantic 总被引：1，自引：0，他引：1
Examination of 38 sediment cores, bottom photographs, 7,000 km of 3.5 kHz reflection profiles and other seismic data from
the southern part of the Nares Abyssal Plain suggests that complex sedimentary patterns and high sedimentation rates can be
largely attributed to effects of a deep boundary current flowing eastward along the north flank of the Greater Antilles Outer
Ridge. It is concluded that the areal dispersal pattern of turbidites on the plain results mainly from Quaternary climatically-induced
fluctuations of the boundary current intensity. 相似文献
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Eleven seismic reflection profiles across Shirshov Ridge and the adjacent deep-water sedimentary basins (Komandorsky and Aleutian Basins) are presented to illustrate the sediment distribution in the western Bering Sea. A prominent seismic reflecting horizon, Reflector P (Middle—Late Miocene in age), is observed throughout both the Aleutian and Komandorsky Basins at an approximate subbottom depth of 1 km. This reflector is also present, in places, on the flanks and along the crest of Shirshov Ridge. The thickness of sediments beneath Reflector P is significantly different within the two abyssal basins. In the Aleutian Basin, the total subbottom depth to acoustic basement (basalt?) is about 4 km, while in the Komandorsky Basin the depth is about 2 km.Shirshov Ridge, a Cenozoic volcanic feature that separates the Aleutian and Komandorsky Basins, is an asymmetric bathymetric ridge characterized by thick sediments along its eastern flank and steep scarps on its western side. The southern portion of the ridge has more structural relief that includes several deep, sediment-filled basins along its summit.Velocity data from sonobuoy measurements indicate that acoustic basement in the Komandorsky Basin has an average compressional wave velocity of 5.90 km/sec. This value is considerably larger than the velocities measured for acoustic basement in the northwestern Aleutian Basin (about 5.00 km/sec) and in the central Aleutian Basin (5.40–5.57 km/sec). In the northwestern Aleutian Basin, the low-velocity acoustic basement may be volcaniclastic sediments or other indurated sediments that are overlying true basaltic basement. A refracting horizon with similar velocities (4.6–5.0 km/sec) as acoustic basement dips steeply beneath the Siberian continental margin, reaching a maximum subbottom depth of about 8 km. The thick welt of sediment at the base of the Siberian margin may be the result of sediment loading or tectonic depression prior to Late Cenozoic time. 相似文献
20.
We present multi channel seismic data recorded at the transition between the Ivorian (rifted) basin and the Côte d’Ivoire–Ghana marginal ridge (formed in a Cretaceous transform margin). The ridge is made of sedimentary sequences continuous with the synrift sediments of the Ivorian basin. Clinoformal structures suggest synrift progradational sedimentation originating from the Brazilian craton, which was located to the south during the Cretaceous. Subsequent to rifting, southward migration of the transform motion isolated the ridge from the Brazilian shelf. In the western part of the marginal ridge, crustal half-grabens are buried by postrifting progradational sedimentation, suggesting important posttransform subsidence. 相似文献