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Tectonic forcing of delta progradation is increasingly being invoked to explain stratal stacking patterns in foreland basins. Nonetheless, the recognition of different types of tectonic forcing and their consequences for the spatial and temporal distribution of accommodation often rely on incomplete data sets and indirect sequence stratigraphic criteria. Previous work has concluded that the Cenomanian-Turonian Frontier Formation of northern Utah, north-west Colorado and south-west Wyoming ('Vernal Delta') owes its origin largely to tectonic overprinting of depositional patterns, although the lack of a comprehensive sequence stratigraphic framework for the unit has hampered evaluation of this claim. This study provides detailed facies and sequence stratigraphic analyses based on outcrop sections and wireline log suites from the Uinta, Piceance and Green River basins. Four genetically related intervals were defined and mapped by using regionally traceable stratigraphic horizons (flooding surfaces and sequence boundaries). Internally, intervals are composed of distal and proximal delta front lithologies, and coastal plain facies. Overall, Intervals 1 to 4 form a major basinward projection of coarse clastic strata generated in response to four separate, high-frequency regressions. Furthermore, a change through time from southward projection of elongate lobes (Intervals 1 and 2) to eastward dispersal and development of a broad, arcuate planform (Intervals 3 and 4) can be explained in terms of changes in prevailing tectonic forcing mechanisms. North-south trending Sevier Orogeny forebulge structures controlled Intervals 1 and 2. West-east progradation (Intervals 3 and 4) was probably controlled by Proterozoic basement lineament reactivation due to Laramide foreland uplifts. Therefore, this study provides direct geological evidence for the initiation of local Laramide deformation as early as 90 Ma. These findings contribute to a more complete understanding of tectonic forcing of coastal to shallow marine successions in foreland basins and the tectonic evolution of the western USA. [ABSTRACT FROM AUTHOR]

A study using multiple techniques provided insight into tectonic influences on ground water systems; the results can help to understand ground water systems in the tectonically active western United States and other parts of the world. Ground water in the San Bernardino Valley (Arizona, United States and Sonora, Mexico) is the main source of water for domestic use, cattle ranching (the primary industry), and the preservation of threatened and endangered species. To improve the understanding of ground water occurrence, movement, and sustainability, an investigation was conducted using a number of complementary methods, including major ion geochemistry, isotope hydrology, analysis of gases dissolved in ground water, aquifer testing, geophysics, and an examination of surface and subsurface geology. By combining information from multiple lines of investigation, a more complete picture of the basin hydrogeology was assembled than would have been possible using fewer methods. The results show that the hydrogeology of the San Bernardino Valley is markedly different than that of its four neighboring basins in the United States. The differences include water quality, chemical evolution, storage, and residence time. The differences result from the locally unique geology of the San Bernardino Valley, which is due to the presence of a magmatically active accommodation zone (a zone separating two regions of normal faults with opposite dips). The geological differences and the resultant hydrological differences between the San Bernardino Valley and its neighboring basins may serve as a model for the distinctive nature of chemical evolution of ground water in other basins with locally distinct tectonic histories. [ABSTRACT FROM AUTHOR]

Aim The biogeography of western North American freshwater molluscs has traditionally been attributed to vicariance associated with late Tertiary rearrangement of landscape based on distributional evidence and the putatively limited dispersal ability of these organisms. We examined the phylogeography of a widely ranging western springsnail ( Pyrgulopsis wongi Hershler, 1989) to test this hypothesis and evaluate the relative importance of vicariance and dispersal in structuring the distribution of this species. Location Southwestern Great Basin (California and Nevada), United States of America. Method Two mitochondrial genes (COI, NDI) were sequenced for 28 populations of P. wongi spanning its entire geographic range, which consists of 10 topographically closed drainage basins. We also sequenced eight closely related congeners, as well as the type species of the closely related eastern North American genus Floridobia Hershler & Thompson, 2002, which was used as the outgroup. Phylogenies based on the combined data set were obtained using several methods, and networks for each gene were generated as an additional means of examining relationships among haplotypes. Partitioning of haplotype variation was studied usingamova, migration between populations was estimated using a coalescent-based method (mdiv), and divergence times were inferred using a locally calibrated molecular clock andmdiv. Results Pyrgulopsis wongi is subdivided into narrowly localized and widely distributed lineages that diverged in the Pleistocene, well after the inception of the contemporary regional landscape. While large ΦST values and the localized geographic distributions of most haplotypes imply absence or negligible contemporary dispersal of this spring-dwelling snail, the pattern of phylogeographic structuring, presence of a few widespread haplotypes, and results of themdiv analyses suggest geologically recent dispersal across drainage divides. Main conclusions Phylogeography of P. wongi conflicts with the traditional vicariance model as it is not structured by the contemporary landscape and is instead indicative of geologically recent dispersal. In the absence of evidence that dispersal of this species occurred through surface water connections during the relevant (Quaternary) time frame, we conjecture that spread may have instead been mediated by transport on waterfowl or via upland stream capture. The non-concordance between phylogeography and landscape reported in this and other recent studies of Pyrgulopsis suggests that members of this diverse and imperiled genus should not be managed using an a priori, ‘watershed as conservation unit’ approach. [ABSTRACT FROM AUTHOR]

Focuses on a study that presented bankfull hydraulic geometry relationships and recurrence intervals for the Southeastern Plain ecoregion and the flatwoods subtype of the Middle Atlantic Coastal Plain ecoregion found within North Carolina's Coastal Plain physiographic province. Methodology; Results of the study; Conclusions.

Investigates the occurrence of emerging contaminants in domestic waste water effluents and their fate during subsequent ground water recharge at two water reuse facilities in the southwestern U.S. employing surface spreading basins. Partial list of pharmaceuticals observed in the aquatic environment; Bulk organic removal; Results of pharmaceuticals in treated waste water effluents and corresponding ground water monitoring wells at both study sites.

Presents a study which discussed the kinematics of basin development during the transition from terrane accretion to tectonics in Alaska. History of tectonics of the Pacific margin; Age of volcanic rocks in Cantwell, Alaska; Overview of volcanic stratigraphy.

Presents a mechanical model of the evolution of the geological structure of the Ventura basin in southern California. Kinematic constraint of the basin; Principles and parameters used in the model; Findings.