Improving reservoir management

现有的方法（地震和电磁）在其提供连续的、低成本的数据的能力方面受到严重的限制，这些数据可以被解释以确定水的位置、体积和在整个储层中的运动。地震勘测通常需要用于深储层相定义的地面生成信号，这是昂贵的，并且在某些情况下难以或不可能获得。此外，基于时间的（4D）地震必须成像相位（以对比气体与水的声速），并且不成比例地看到变化的体积。常规EM对储层内的电导率变化具有敏感性，但仅在存在电导率对比（例如含盐地层）的情况下提供信息，而非枯竭储层。开发和商业化一个强大的嵌入式重力传感器将解决这些限制，并提供一个地下验证和监测能力的一步变化。重力对地震和电磁具有固有的优势。重力信号始终存在，并且不需要源来生成响应。此外，通过检测质量或密度的差异，重力为地震（测量声速）和EM（测量微分电阻率）提供了补充和独立的测量。4D地震加重力的组合将导致减少误差和改进地震解释。与EM不同，重力是深度阅读-能够穿透高达2000 '。重力，特别是MEMS技术，成本较低（每个传感器只有几磅）。MEMS技术还为井眼部署提供了其他明显的优势，包括易于组装和包装以及定向的灵活性。由于这些属性，MEMS重力传感器是支撑井筒中的周期性或低成本永久传感器阵列系统的最佳技术。该项目旨在试点开发一种用于储层成像的新型MEMS重力工具。

Existing methods (seismic and electromagnetic) suffer from serious limitations in their ability to provide continuous, low cost data that can be interpreted to determine water location, volume, and movement throughout a reservoir. Seismic surveys typically require a surface generated signal for deep reservoir phase definition which is costly and in some cases difficult or impossible to obtain. Also, time based (4D) seismic must image phases (to contrast gas versus water acoustic velocity) and does not proportionately see varying volumes. Conventional EM has sensitivity to conductivity changes within the reservoir but only provides information where there are conductivity contrasts such as saline formations, but not depleted reservoirs. Development and commercialization of a robust miniaturised gravity sensor would address these limitations and provide a step change in subsurface verification and monitoring capability. Gravity has inherent advantages to seismic and EM. The gravity signal is always present and does not require a source to generate a response. Also, by detecting differentials in mass or density, gravity offers complementary and independent measures to seismic (which measures acoustic velocity) and EM (which measures differential resistivity). The combination of 4D seismic plus gravity will result in reduced error and improved seismic interpretations. Unlike EM, gravity is deep reading - able to penetrate up to 2000'. Gravity, and in particular MEMS technology, is lower cost (only a few pounds per sensor). MEMS technology also offers other distinct advantages for wellbore deployment, including ease of miniaturizaton and packaging and flexibility on orientation. Because of these attributes, the MEMS gravity sensor is the optimum technology to underpin a system of periodic or low cost permanent sensor arrays in wellbores. This project aims to pilot the development of a new MEMS gravity tool for reservoir imaging.