Novel seismic strategies for monitoring fluid flow in C02 sequestration experiments and heavy-oil fields

加拿大拥有世界上第二大探明石油储量。不幸的是，这些储量主要由沥青砂组成，开采和提炼成本非常高。重油开采导致的二氧化碳排放量平均是轻油开采的三倍。因此，以环境友好和可持续的方式对这些重油进行商业开采要求制定适当的二氧化碳封存战略，以减少温室气体排放到大气中。然而，公众和政界不太可能接受二氧化碳封存，除非我们能够可靠地检测到储层内部的流体迁移，最重要的是，检测到任何二氧化碳泄漏的存在。该提案概述了以下新方法：(1)开发强大、可靠和高灵敏度的工具来监测二氧化碳流体迁移和检测泄漏；(2)与常规油气采集和处理要求相比，研究降低二氧化碳监测成本的策略；(3)改进对重油液化的检测，降低蒸汽油比，从而降低排水成本和环境足迹。这将通过整合微地震记录和地面地震数据中的信息，以及开发新技术来区分现场压力和流体含量的变化来实现。这是相关的，因为压力扰动先于流体流动。因此，对压力扰动的检测可以及时提供潜在流体流动路径和泄漏点的信息，远远早于实际流体在二氧化碳封存点逃逸。改进油藏模拟模型，提高稠油驱油效果。这种稠油开采和二氧化碳封存的基础和应用研究对于保持加拿大在油气勘探和开发方面的领先地位至关重要。

Canada has the second largest proven oil reserves in the world. Unfortunately these reserves are predominantly composed of tar sands with very high extraction and refining costs. Heavy-oil exploitation leads also in average to three times larger CO2 emissions than lighter oils. Commercial exploitation of these heavy oils in an environmentally friendly and sustainable fashion therefore demands the development of suitable CO2 sequestration strategies in order to reduce the emission of greenhouse gases into the atmosphere. Yet public and political acceptance of CO2 sequestration is unlikely unless we are able to detect fluid migration inside the storage reservoir reliably and most importantly the presence of any CO2 leakage. This proposal outlines new approaches to (1) develop robust, reliable and highly sensitive tools to monitor CO2 fluid migration and detect leakage; (2) examine strategies to reduce CO2 monitoring costs compared with conventional hydrocarbon acquisition and processing requirements; (3) improve detection of heavy-oil liquefaction to reduce steam-to-oil ratios thereby reducing drainage costs and environmental footprints. This will be achieved by integrating information contained in both microseismic recordings and surface seismic data, and by developing novel technologies to differentiate between in-situ variations in pressures and fluid contents. This is relevant since pressure perturbations precede fluid flow. Detection of pressure perturbations can therefore provide timely information on potential fluid flow pathways and leakage spots, well in advance of the actual fluids escaping in CO2 sequestration sites. It can also help to improve reservoir simulation models to enhance heavy-oil drainage. Such fundamental and applied research in both heavy-oil extraction and CO2 sequestration is essential to keep Canada at the forefront of hydrocarbon exploration and exploitation.