The use of integrated ¯uid inclusion studies in constraining oil charge history and reservoir compartmentation: examples from the Jeanne d'Arc Basin, offshore Newfoundland John Parnell a, * , David Middleton a , Chen Honghan a , Don Hall b a Department of Geology and Petroleum Geology, University of Aberdeen, Meston Building, Kings College, Aberdeen AB24 3UE, UK b Fluid Inclusion Technologies Inc., 2217 North Yellowood Avenue, Broken Arrow, OK 74012, USA Received 23 December 2000; received in revised form 5 March 2001; accepted 10 March 2001 Abstract A demonstration study of the application of ¯uid inclusion data from the Jeanne d'Arc Basin shows that it provides valuable information about the oil charge history and reservoir compartmentation. Oil inclusions occur within both cements and annealed microfractures, indicating that diagenesis continued after or during oil emplacement, and that fractures were involved in oil migration. The oil inclusions occur in cements subsequently deformed in granulation seams, showing that the earliest oil charge pre-dated the end of deformation. Oil inclusions are suf®ciently abundant to measure oil geochemistry. In a comparison between adjacent barren and oil-bearing wells in the Terra Nova Field, oil inclusions in the barren well testify to the breaching of a trap. Bulk volatile data ¯uid inclusion stratigraphy, FIS) record the occurrence of hydrocarbon inclusions throughout sandstone reservoir sections, and also give indications of seepage to shallower levels. q 2001 Elsevier Science Ltd. All rights reserved. Keywords: Fluid inclusions; Fluid inclusion stratigraphy; Diagenesis; Jeanne d'Arc Basin 1. Introduction Basins on the Atlantic Margin often display a complex history of ¯uid migration, the successful modelling of which is crucial to the successful appraisal of potential hydrocarbon systems e.g. Parnell, Carey, & Duncan, 1998; Iliffe et al., 1999). During and after subsurface ¯uid migration, including oil migration and charging of reser- voirs, small ¯uid samples are encapsulated as inclusions during cement precipitation and microfracture annealing. These can be examined using microthermometry, ultraviolet microscopy, geochemistry and other techniques, enabling us to reconstruct the temperatures, salinities and compositions of ¯uids at the time of migration. Identi®cation of oil inclu- sions allows the characterisation of former oil charges long after the original intergranular petroleum has been removed from the system. In addition to conventional ¯uid inclusion studies, ¯uid inclusion stratigraphy FIS) is a bulk volatile analysistechniquethatallowspore¯uidstrappedininclusions to be chemically characterized in cuttings and core, in large numbers of samples Hadley, Hall, Sterner, & Wells, 1997). The data can yield valuable information on migration path- ways, pay delineation/proximal pay detection, petroleum type oil vs. gas, oil type) and ¯uid compartmentation. We illustrate this approach with data from the Jeanne d'Arc Basin Fig. 1), particularly from a pair of wells in the Terra Nova ®eld Fig. 2). This paper represents a demon- stration of the potential of ¯uid inclusion data to help under- stand the petroleum system offshore eastern Canada. 2. Geological setting The Jeanne d'Arc Basin is one of several Mesozoic exten- sional rift basins developed in the North Atlantic border- lands Enachescu, 1987). Following initial Triassic rifting which involved accumulation of ¯uvial and lacustrine clastic sediments, evaporites and basalts, the basin experi- enced Jurassic marine transgression and deposition of lime- stones, dolomites, sandstones and shales, including proli®c Kimmeridgian source rocks. Lower Cretaceous sedimenta- tion was dominated by progradational deltaic pulses which deposited several widely developed sandstone units. Faults associated with late Jurassic±Lower Cretaceous extension Marine and Petroleum Geology 18 2001) 535±549 0264-8172/01/$ - see front matter q 2001 Elsevier Science Ltd. All rights reserved. PII: S0264-817201)00018-6 www.elsevier.com/locate/marpetgeo * Corresponding author. Tel.: 144-01224-273464; fax: 144-01224- 272785. E-mail address: j.parnell@abdn.ac.uk J. Parnell).