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Reservoir evaluation, which works throughout the oil and gas development, has always focused on exploration and development needs [1-3].There are many influencing factors and data in the evaluation process, thus it’s difficult to select the reasonable evaluation parameters and methods. Selecting the appropriate evaluation parameters and evaluation methods can improve the accuracy of evaluation, reduce the evaluation workload. Regional studies have shown that Delta-front sub-facies is the major sedimentary type of the Chang 8 in Baibao oilfield, widely distributed delta distributary channel and mouth bar sands are good oil and gas reservoirs in the area. In this paper, cluster analysis reservoir evaluation is using to obtain their correct evaluation parameters, in order to provide the basis for further development.

By core observation and logging in Block8, Jinglou oilfield, we distinguished the sedimentary structure characteristics and the logs’ features of subaqueous distributary channel, mouth bar, sheet sand and interdistributary. Then we promoted it in the whole region, and characterised the sedimentary faices of every layers. So we provide a reliable geological basis for progressive development in research area.

With rapid development of economy, the crisis of land resources is faced. Land expansion by enclosing sea in estuaries has become an important carrier for city space extension. In this paper,the large-scale marine reclamation project in the Oujiang River Estuary (ORE) of Wenzhou shoal was taken as an example.Based on the intoduction of the study area,the 3D marine numerical model (EFDC) was setup and used for simulation of sediment enviroment and morphological changes induced by the reclamation. The results indicated that the project doesn’t have obvious adverse effects on its nearby sediment environment and seabed. On the contrary, it settles the problem of mouth bar of the ORE and provides some advantages to maintain and steady the deep water channel and improve the sail condition from the north mouth of Oujiang River to Huangda’ao channel.

On the base of drilling cores, summarizing some sedimentary facies marks, such as grain size characteristics, sedimentary structures, log curve, etc, it is analyzed the sedimentary characters of fan delta of Yingcheng formation in Lishu fault depression according to drilling well sedimentary analysis. The study area grows two subfacies, fan-delta plain and front fan-delta, existing 6 microfacies which are debris flow, distributary channels, interdistributary bay, submerged distributary channe, mouth bar and submerged distributary interchanne. Then the depositional model of gentle slope type fan delta is established.On the plane, fan delta existing in this area has characters of contiguous development and mixed-source deposition; In the longitudinal direction, deposition lithologic section developed in the period of water withdrawal is built on the retrograding lithologic section developed in the period of water inlet.

Yulin area of Changqing gas field in Ordos basin has the favorable conditions for gas accumulation in Shan 2 Member, which is the main productive layer to increase reserve and production. Based on the research of gas pool forming conditions, the distribution rules of gas in Shan 2 Member in Yulin area of Changqing gas field can be concluded: coals, swap dark mudstones and delta front sandbodies are well-developed vertically, the conditions of reservoir-forming combination for self-generation and self-preservation are processed; the sandbodies developed in submerged distributary channel and mouth bar microfacies of delta front have a high content of quartz, which have a good physical properties and a high gas production. There is a good relationship between the distribution of gas pools and the maturity of sandstone, the value 6 of maturity index (86% quartz content) can be used to delineate the zones of gas enrichment and productivity. This rule can guide the exploration and production of this area in next step.

Based on the observation and description of single well and outcrops and the analysis of reservoir compositions, petrology, clastic structure and sedimentary structure,this paper determines the sedimentaty facies characteristics of Tanzhuang formation. The types of sedimentary facies in late Triassic epoch are delta front,shallow lake and semi-deep lake. The delta front develops subaqueous distributary channel, mouth bar and distal bar. Lacustrine facies develops shallow lake mud, shallow lake sand bar, turbidite sand and semi-deep lake mud.The reservoir rock formations in this area are lithic sandstone,feldspathic lithic sandstone with high content of feldspar and debris.The sedimentary structures include ripple, scour surface and cross-bedding are identified.

Es2 8th sand group in Shengtuo oilfield is a typical braided river delta front deposition. Through depositional physical simulation, the development mode of mouth bar and its main controlling factors were summarized. Physical model and experiment scheme were set up according to similarity criterion and the depositional background in research area. One provenance and three times simulation was designed to simulate three single layers within Es2 8th sand group respectively. Development mode of mouth bar was summarized with three single mouth bars based on swing conditions of rivel estuary and two composite mouth bars according to whether they are developed at the same time.

L Oilfield construct as a whole for a wide and gentle anticline, the constructor East steep west slow in constructing the eastern part of the main part of the fault development of the western fault is relatively small, types of traps are faulted anticlines. Type of reservoir rock, siltstone and fine sandstone, sandstone and conglomerate, fine-grained sandstone and siltstone; deposition rhythm is rhythm, including a counter-rhythm, uniform rhythm; Cretaceous reservoir deposition mainly delta plain distributaries channel, the deposition of the Jurassic reservoir delta front, subaqueous distributaries channel and mouth bar; cretaceous reservoir average porosity of 19.3%, average permeability of 30 × 10 - 3μm2, in holes, low permeability reservoir sand body has a more serious layer, flat heterogeneity; Jurassic reservoir average porosity 26%, average permeability of 323 × 10-3μm2 to belong to the hole. in permeability reservoir. Water injection to maintain reservoir pressure development, research to determine the reservoir formation pressure to maintain the level of 0.83 times the original pressure, the initial development technology boundaries with more than 1.2 compensates water injection system pressure of 35MPa.

Tahe Oilfield is an significant petroleum exploitation and development area in Tarim Basin for SINOPIC. Carboniferous Kalashayi Formation has become an important oil-bearing series for increasing and maintaining production, and for finding backup resource in this Oilfield. Based on the theories and methods of sedimentology, by using the sesmic, log and core data, the sedimentary facies of Carboniferous Kalashayi Formation in the south of Tahe Oilfield are analyzed deeply. Through the study of characteristics of the rock type and texture,sedimentary structure, sedimentary sequence, stratic structure, paleontology, geochemistry and geophysics of Kalashayi Formation, the Sand-shale Section is attributed to tidal flat deposits which has a nature of estuary. The study area are mainly dominated by intertidal zone, including mud flat, sand-mud flat, sand flat, tidal channel and mouth bar microfacies. The Up-mudstone Section developed lagoonal facies. This study provides favorable support for the further petroleum exploration in study area.

Through the research on actual measurement 106km geological profile, the hydrocarbon source rocks mainly develop the third member of Jiufotang formation, followed by the second member. There are five distribution areas where have been divided hydrocarbon source rocks thickness is more than 400m in study area. Among them, Jiufotang area has the greatest sedimentary thickness of hydrocarbon source rocks, while Siguanyingzi-Sanjiazi area has the largest area where hydrocarbon source rocks are more than 400m. Oil shale is good hydrocarbon source rock, while dark gray and black gray mudstone (or shale) are relatively poor. The fan delta front subaqueous distributary channel and mouth bar are well-developed in basin’s fault zone and also the important favorable reservoir, followed by braided delta front mouth bar, subaqueous distributary channel and distal bar developing in northwestern area of the basin. There are four forms of source-reservoir-cap combination: (1) hydrocarbon source rock in the above layer and reservoir in the below layer; (2) hydrocarbon source rock and reservoir in the same layer; (3) normal form; (4) fingerlike intersection. The combination of fingerlike intersection is the most important forms in study area. Fan delta facies next to lacustrine facies is favorable exploration area.