In this study, production controlling factors were fully reviewed and analyzed with more than 100 existing vertical evaluation wells and 20 horizontal producers from Chang 7 tight oil reservoir in Longdong area. Both vertical and horizontal wells show that thicker oil pay, more stage fracs, larger volume fluid and proppants have very strong correlation with higher productivity. Then an integrated reservoir modeling workflow is provided. All petrophysical properties, geology understanding, reservoir geomechanics features are included into a integrated geoscience model built with both horizontal wells and surrounding vertical wells within and around one typical production pad. Integrated geoscience model can provide more insights to accurately unlock upside potential above or below shale interval by hydraulic fracturing in horizontal lateral if horizontal well is unexpectedly landed into shalestone intervals. A detailed single well fracturing optimization from stages and perforations selection, cluster spacing, fracturing sequence to fracturing sand volume is also performed based on integrated geoscience model. A typical well fracturing design generated from integrated reservoir modeling workflow, some shalestone intervals with upside potential are successfully identified and easily reached breakdown pressure with current pumping art and surface limitations. This breakthrough of fracturing shalestone is the first success in Chang 7 tight oil reservoir and well production rate is enhanced 20% more than offset wells. Another important application with integrated geoscience model is to help identify and prevent fracture hit during stimulation operation. Some solid conclusions can be drawn from the study that reservoir property including heterogeneity, natural fractures, interlayer barrier thickness play more important role than engineering parameters such as pumping volume, treating pressure etc.

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