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Abstract
The onshore area of the Northeastern United States is lacking in reservoir intervals appropriate for storing large volumes of carbon dioxide (CO2). It is proposed that the geologic conditions found offshore of the Eastern Seaboard are conducive to the safe storage of large volumes of CO2 generated from anthropogenic activities in the region (Schrag, 2009). Little subsurface investigation has occurred in this area since it was initially explored for hydrocarbons in the mid-1970s. Can newer data evaluation techniques be applied to older data to ascertain the CO2 storage potential of the Atlantic Outer Continental Shelf?

Schlumberger Carbon Services recently performed an initial site evaluation of storage potential for CO2 within the Cretaceous intervals near the Baltimore Canyon Trough utilizing vintage wireline, core, and 2D seismic data to develop a geocellular model to simulate CO2 injection and storage. The evaluation site is centered approximately on the COST B-2 well, located about 70 miles offshore of New Jersey and drilled as a stratigraphic test in 1976. The COST B-2 well and others drilled in the late 1970s and 80s penetrated a Lower Cretaceous interval abundant in channel and mouth-bar sands deposited in a wave-dominated delta-front to nearshore depositional environment. Petrophysical analysis of available wireline data indicates these sands exhibit porosity and permeability ranges adequate for the potential injection of CO2. Additonally, log analysis indicates laterally extensive and vertically thick marine shales overly these potential reservoir intervals and provide an appropriate seal across the region. This petrophysical analysis was integrated with interpretations from available two dimensional seismic lines to investigate the spatial potential of the targeted sediments to store large volumes of injected CO2.

Introduction
In order to properly assess the potential for CO2 storage of any specific geologic formation at any specific geologic site, the primary attributes for the subsurface interval being investigated must be evaluated for storage potential. We will explain analysis of the key variables associated with the construction of a subsurface model that can adequately evaluate the potential Storage Capacity, Injectivity, and Containment for CO2 storage. The site being investigated in this study is located within the United States (U.S.) Atlantic Outer Continental Shelf (OCS), approximately 70 miles east of the upper New Jersey coastline in the vicinity of the COST B-2 well (Figure 1). For this initial assessment, vintage wireline, core, and two dimensional (2D) seismic data, acquired during exploration for hydrocarbons in the late 1970s and early 1980s at or near the proposed site, were utilized to develop a geocellular earth model and reservoir simulation model so that injection rates, plume size, well design, and construction costs could be estimated.