I-Corps: Optical device for the measurement of shale swelling

I-Corps项目更广泛的影响/商业潜力是开发一种仪器来测量富含粘土的地质地层（如泥岩或页岩）的膨胀。对于油气或地热勘探的井眼设计，以及对地下储层二氧化碳的长期密封完整性监测，都需要对页岩膨胀的准确了解。如果页岩对水的敏感性测量不准确，可能会导致一些问题，如井筒坍塌、管柱卡钻、钻头包球、意外裂缝扩展到邻近地层或二氧化碳泄漏，从而造成经济和环境后果。该光学膨胀仪可以帮助钻井工程师、生产工程师、钻井服务公司、油田实验室和政府监管机构的泥浆测井人员获得页岩膨胀的准确测量数据。这个I-Corps项目研究了一种用于测量页岩膨胀的新型光学膨胀仪的商业可行性。该仪器将数字图像相关（DIC）技术原理应用于从涂有斑点图案并浸没在水中的岩石样品中拍摄的图像。利用DIC技术将不同时间间隔拍摄的图像与原始图像进行对比，可以测量岩样的变形情况。该设备提供了膨胀的全景图，而不是像目前的工业实践那样提供单一的膨胀平均值。这一特征非常重要，因为页岩地层具有复杂的矿物学特征，其性质在毫米级或毫米以下发生变化。该装置还可以提供页岩膨胀的各向异性值。这一特征很重要，因为页岩在层压方向与垂直层压方向的行为通常不同。页岩的各向异性和非均质性是表征页岩与水接触时复杂行为的重要考虑因素。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this I-Corps project is to develop an apparatus to measure the swelling of clay-rich geologic formations, such as mudstones or shales. Accurate knowledge of shale swelling is required for the design of wellbores drilled for hydrocarbon or geothermal exploration and for the long-term seal integrity monitoring for carbon dioxide storage in subsurface formations. Inaccurate measurement of shale sensitivity to water can cause problems such as wellbore collapse, pipe sticking, bit balling, unintended fracture growth to neighboring formations, or carbon dioxide leakage with economic and environmental consequences. The proposed optical swell-meter may help drilling engineers, production engineers, and mud loggers in operating and service companies, oil field laboratories, and government regulatory agencies to obtain an accurate measurement of shale swelling.This I-Corps project investigates the commercial feasibility of a new optical swell-meter apparatus for the measurement of shale swelling. This apparatus applies the principles of digital image correlation (DIC) techniques on the pictures taken from a rock sample painted with a speckled pattern and submerged in water. Comparing the pictures taken at different time intervals with the original picture using DIC techniques, the deformation of the rock sample can be measured. The proposed device provides full-field maps of swelling instead of a single average value of swelling as is the current industry practice. This feature is important because shale formations have complex mineralogy and their properties change at or below millimeter scales. The proposed device can also provide anisotropic values of shale swelling. This feature is important since shale behavior is usually different in the direction of lamination compared to perpendicular to lamination. The anisotropic and heterogenetic nature of shales are important considerations in the representation of complex shale behavior in contact with water.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.