Carbon isotope compositions of organic matter in fine-grained siliciclastic units deposited above and below glacial diamictite at the base of the ca. 2.45–2.22 Ga Huronian Supergroup in Ontario, Canada were studied to constrain relationships between profound fluctuations in the exogenic carbon cycle and dramatic climate changes at the beginning of the Proterozoic Eon. In both drill core and out...

The Middlebury Formation is a Middle Ordovician limestone deposited on the margin of Laurentia during the collision of the Ammonoosuc Arc with Laurentia. Tectonic processes such as subsidence can have an effect on the forearc basin morphology such that the sedimentation in the basin is influenced and the stratigraphy will reflect such tectonic processes. The purpose of this study is to examine ...

In this paper, we combine a probabilistic neural method with radial-bias functions in order to construct the lithofacies of the wells DF01, DF02 and DF03 situated in the Triassic province of Algeria (Sahara). Lithofacies is a crucial problem in reservoir characterization. Our objective is to facilitate the experts’ work in geological domain and to allow them to obtain quickly the structure and ...

Truncated Gaussian simulation (TGS) and plurigaussian simulation (PGS) are widely accepted methods for generating realisations of geological domains (lithofacies) that reproduce contact relationships. The realisations can be used to evaluate transfer functions related to the lithofacies occurrence, the simplest ones of which are the probability of occurrence of each lithofacies and the most pro...

Unconventional shale reservoirs as the result of extremely low matrix permeability, higher potential gas productivity requires not only sufficient gas-in-place, but also a high concentration of brittle minerals (silica and/or carbonate) that is amenable to hydraulic fracturing. Shale lithofacies is primarily defined by mineral composition and organic matter richness, and its representation as a...

We determined that the spatial heterogeneity in aquifer properties governing the reactive transport of volatile organic contaminants is defined by the arrangement of lithofacies. We measured permeability (k) and perchloroethene sorption distribution coefficient (Kd) for lithofacies that we delineated for samples from the Canadian Forces Base Borden Aquifer. We compiled existing data and collect...

Deep-water massive (featureless) sands are commonly interpreted as indicators of flow conditions during or shortly after deposition and are almost never interpreted to reflect post-depositional homogenization due to bioturbation. Deep-water deposits of the lower Rio Dell Formation (Pliocene), Eel River basin (NW California), however, reveal previously unrecognized cryptically bioturbated fabric...

5 Interspecific relationships 48 INTRODUCTION 5 Predation 49 Location and geologic setting 5 Competition 50 Previous work 7 Commensalism 50 Approaches and study objectives 7 DEPOSITIONAL ENVIRONMENT AND Vertebrate paleontology 8 PALEOECOLOGIC SYNTHESIS 50 Paleobotany 8 Climate and paleogeography 50 Stratigraphy and correlation 8 Succession of the ancient communities 51 Acknowledgments 12 Summar...

Unconventional reservoirs are keys to oil and gas exploration and development, especially shale gas reservoirs. Discriminated shale gas reservoir lithofacies are, in particular, a primary problem in shale gas reservoir engineering. The mineral composition will affect both absorbed and free gas contents, therefore their identification is important. The mineral composition is one part of lithofac...

Abstract: The organic-rich Marcellus Shale was deposited in a foreland basin during Middle Devonian. In terms of mineral composition and organic matter richness, we define seven mudrock lithofacies: three organic-rich lithofacies and four organic-poor lithofacies. The 3D lithofacies model is very helpful to determine geologic and engineering sweet spots, and consequently useful for designing ho...