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The conventional petroleum field in Jiyang Depression has always been the main battlefield of exploration and development in Shengli Oilfield. It has experienced more than 60 years of exploration and development and entered the mature exploration stage as a whole， but it still has a relatively large scale of reserve increase every year， which is not consistent with the traditional growth trend of proven petroleum-in-place in oil and gas-bearing basins. The critical issues concerning the exploration decisions of Shengli Oilfield need to be clarified urgently， including the growth law of the conventional proven petroleum-in-place in Jiyang Depression， the strong trend of reserve increase， and the main fields for reserve increase. By analyzing the exploration process of Jiyang Depression， the geological characteristics， resource conditions， exploration investment， theory and technology， resource sequence， and other exploration elements were analyzed， revealing the exploration discovery law of conventional petroleum in Jiyang Depression. The broom-shaped model prediction method and proven rate method of resource were used to predict the growth trend of conventional proven petroleum-in-place. The scale and favorable direction of future reserve increase of conventional petroleum in Jiyang Depression were clarified by analyzing the main fields with reserve increase. The results show that the complex geological characteristics of Jiyang Depression and the relatively abundant remaining resources determine the diversity of exploration objects， the tortuosity of the exploration process， and the long-term nature of exploration history. The conventional petroleum in Jiyang Depression can still maintain a long period of stable reserve increase under conditions of ensuring a relatively stable exploration investment， continuing to innovate the exploration theory and key technologies， and maintaining a relatively reasonable resource sequence. Jiyang Depression can still produce about 2.5 × 108 t of conventional proven petroleum-in-place in the next 10 years under the current economic and technical conditions and the relative guarantee of exploration investment. It is pointed out that the Neogene river sandstone reservoir， lithologic oil and gas reservoirs in the Upper Submember of the 4th Member of the Eocene Shahejie Formation（Es4U）-the Lower 3rd Member of the Eocene Shahejie Formation（Es3L）， and other mature fields are still the ballast stones for stable reserve increase. Kongdian Formation-the deep field of the Lower Submember of the 4th Member of the Eocene Shahejie Formation（Es4L） is an essential field for large-scale reserve increase， and the pre-Paleogene buried hill is a favorable direction for the petroleum enrichment and high yield. In the future， the exploration progress in the unconventional and new energy fields should be closely tracked， and the research results of the growth law and the reserve increase trend of conventional proven petroleum-in-place in Jiyang Depression should be constantly improved and revised to make them more conform to the development trend of oilfield exploration and guide the oilfield exploration decisions.

Various symbiotic/associated oil and gas resources have been found in the exploration area of Shengli Oilfield， and some of them serve as strategic resources for guaranteeing the security of national defense， agriculture， high-tech， and other industries， which are of great value in development and utilization. The current exploration and development status， occurrence characteristics， ore-forming conditions， and comprehensive utilization prospects of helium， brine （potassium salt）， and uranium ore that have been deeply studied and industrially produced in China were analyzed. The results show that ① the high helium anomalies are mainly distributed in more than 10 areas of the Jiyang Depression and Qaidam Basin， as well as in multiple layers of the Proterozoic-Cenozoic， associated with conventional natural gas， non-hydrocarbon gas， and shale gas； ② Jiyang Depression and Qaidam Basin provide the paleoclimate and palaeoenvironment for developing brine （potassium salt） from the Paleogene to the Quaternary. The oilfield water in Dongying Sag contains abundant amounts of bromine， lithium， and potassium， and more potassium and lithium are found in the oilfield water in Qaidam Basin， with the content in some areas reaching industrial grade； ③ the sandstone is the primary type of uranium ore. The multiple wells in Chepaizi Uplift exhibit highly abnormal gamma values in the Cretaceous and Neogene， indicating that this area is the most favorable prospective area of associated uranium ore. In other exploration areas of Shengli Oilfield， such as Tuha Basin， Qaidam Basin， and Jiyang Depression， the forming conditions for uranium ore are observed， including uranium sources， structures， lithofacies， hydrogeology， etc.， and natural gamma logging data from some wells show high abnormal values. Overall， the symbiotic/associated oil and gas resources in the exploration area of Shengli Oilfield show the characteristics of various types， multiple layers， and wide abnormal areas. It is necessary to fully take the natural advantages of Shengli Oilfield in terms of basic exploration data， basic geological achievements， and engineering facilities，to systematically carry out research on the reservoir forming （ore-forming） law of symbiotic/associated oil and gas resources， evaluate resource potential， and innovate extraction technology as soon as possible， to achieve a new business growth pole.

The Tertiary stratigraphic reservoirs in Jiyang Depression are characterized by small buried-depth, long distance of trap from source, low oil-bearing height and poor oil physical property. Oil-bearing height is mainly determined by four factors: expulsion rate of source rock, migration distance, dip angle of carrier bed and capillary resistance force. Of these four factors, the expulsion rate can be expressed by the pressure factor gradient of source rock, the migration distance can be expressed by the horizontal and vertical distances between trap and source, and the capillary resistance force in carrier beds can be expressed by the capillary pressure in trap reservoirs. From the statistics of 62 stratigraphic reservoirs, oil-bearing height is in positive correlation with pressure factor gradient and dip angle of carrier bed and in negative correlation with horizontal and vertical distances between trap and source and capillary resistance force. On the basis of relations analysis between oil-bearing height and single factors, the multi-parameter match expression for the stratigraphic reservoir oil-bearing height has been established through multiple regressions. The application results show that the predicted value from match expression matches well with the true value. The expression can be used for the prediction of oil-bearing height of Tertiary stratigraphic reservoirs in Jiyang Depression. 摘要: 济阳坳陷第三系油藏总体上具有埋藏浅、圈源距离远、含油高度低、原油物性较差等特点。油藏含油高度主要受控于烃源岩排烃量、运移距离、输导层倾角、输导层毛细管阻力等4大因素。其中, 烃源岩排烃量可用烃源岩压力系数梯度、运移距离可用圈源平面距离和圈源埋深差、输导层毛细管阻力可用圈闭储集层毛细管压力等参数进行表征。从62个地层油藏统计结果来看, 含油高度与烃源岩压力系数梯度、输导层倾角呈较好正相关关系, 而与圈源平面距离、圈源埋深差、储集层毛细管压力等呈较明显负相关关系。在含油高度与单因素关系分析基础上, 通过多元回归, 建立起了地层油藏含油高度多参数拟合关系式。应用结果表明, 该拟合关系式预测值与实际值吻合度较高, 可用来对济阳坳陷第三系油藏含油高度进行定量预测。 Key words: stratigraphic reservoir, oil-bearing height, control factor, quantitative prediction, Jiyang Depression