Back to Exploration – 2008 CSPG CSEG CWLS Convention 9 Sedimentological and Neoichnological Trends in a Microtidal Barrier Island / Embayment System, New Brunswick, Canada Tyler Hauck* University of Alberta, Edmonton, AB thauck@ualberta.ca S. George Pemberton and Murray Gingras University of Alberta, Edmonton, AB, Canada and Shahin Dashtgard Simon Fraser University, Burnaby, BC, Canada Summary In the last half-century there has been a marked increase in the understanding of the facies architecture, stratigraphy, and sequence stratigraphy of transgressive incised-valley fill systems. This understanding has, in part, stemmed from and increase in the number of studies undertaken in recent estuarine environments along the world’s coastlines. These studies facilitate the understanding of the distribution of facies in estuaries, and the physical and chemical processes by which these facies were deposited. Understanding the distribution of facies, and more specifically those of reservoir potential, is important in the search for hydrocarbons in estuarine deposits. This is especially critical considering that estuarine deposits within incised-valley fills account for an estimated 25% of off-structure petroleum plays in clastic reservoirs worldwide (Boyd et al., 2006). In addition to recent sedimentological and geomorphological advancements to estuarine models, significant advances in the delineation of estuarine strata have been accomplished through ichnological and neoichnological studies. Estuaries comprise a distinct set of environmental conditions (i.e., those conditions associated with brackish-water settings) that act as significant limiting factors to infaunal colonizers. Through work in both ancient and modern estuarine deposits, it was recognized that brackish-water conditions result in distinct, recognizable, and recurring trace- fossil assemblages (Pemberton et al., 1982; Frey and Howard, 1986; Pemberton and Wightman, 1992; Wightman and Pemberton, 1997; Gingras et al., 1999; Pemberton et al., 2001). The studies resulted in the establishment of the brackish-water ichnological model that greatly aided in the predictability of estuarine facies in the subsurface, and has proven to be a very powerful tool in paleoenvironmental analysis of estuarine strata (MacEachern et al., 1999; Zonneveld et al., 2001; Buatois et al., 2002; Hubbard et al., 2004; Bann et al., 2004). Modern neoichnological work has largely aimed at furthering the use of ichnology in paleoenvironmental analysis in settings characterized by large tidal ranges (i.e., meso- to