Mycobacteriophages are viruses that infect mycobacterial hosts such as Mycobacterium smegmatis and Mycobacterium tuberculosis. All mycobacteriophages characterized to date are dsDNA tailed phages, and have either siphoviral or myoviral morphotypes. However, their genetic diversity is considerable, and although sixty-two genomes have been sequenced and comparatively analyzed, these likely represent only a small portion of the diversity of the mycobacteriophage population at large. Here we report the isolation, sequencing and comparative genomic analysis of 18 new mycobacteriophages isolated from geographically distinct locations within the United States. Although no clear correlation between location and genome type can be discerned, these genomes expand our knowledge of mycobacteriophage diversity and enhance our understanding of the roles of mobile elements in viral evolution. Expansion of the number of mycobacteriophages grouped within Cluster A provides insights into the basis of immune specificity in these temperate phages, and we also describe a novel example of apparent immunity theft. The isolation and genomic analysis of bacteriophages by freshman college students provides an example of an authentic research experience for novice scientists.

The Swauk Basin lies between the Straight Creek and Entiat–Leavenworth fault systems in the central Cascades of Washington and is one of several early Tertiary strike-slip basins in the Pacific Northwest. In this paper, seven informal stratigraphic units are recognized in the lowest portion of the basin fill—the lower and middle Eocene Swauk Formation—in the eastern part of the basin. These units have a stratigraphic thickness of more than 4800 m and were deposited in alluvial fan, braided river, meandering river(?), lacustrine-deltaic, and lacustrine environments. Rapid facies changes and reversals in paleocurrent directions indicate numerous tectonically controlled drainage reorganizations. Sediments were mainly derived from crystalline rocks to the east, north, and west (?), and sediment accumulation rates were high (about 64 cm/1000 years). The Leavenworth fault has a complex history and, periodically, formed the eastern margin of Swauk Basin. During the final phases and shortly after deposition of the Swauk Formation, the vertical sense of slip on the Leavenworth fault reversed itself and the trace of the fault shifted westward, leading to formation of the Chiwaukum Graben. Following deposition, the Swauk Formation was deformed into west-northwest-trending folds and then intruded by north–northeast-trending dike swarms. Based on similarities with other well-documented strike-slip basins, we conclude that strike-slip faulting was the main control on the deposition and deformation of the Swauk Formation.

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The Moomba and Big Lake Gas Field area has been actively explored for 25 years. However, recent drilling and field studies have identified new reservoir objectives for appraisal of established fields and for exploration in wildcat areas. Cooper Basin reserves have been increased and further additions are likely. Integration of drilling, production and pressure data for the Moomba and Big Lake Fields has resulted in the discovery of a structural-stratigraphic trap on the south-west flank of the Moomba Dome. Moomba-65 flowed gas at 9.8 MMCFD (0.27 Mm3/d) from deltaic sandstone of the Epsilon Formation (Early Permian). Similar plays are likely to be found on the flanks of other Cooper Basin fields and will become increasingly important as opportunities for conventional crestal tests of anticlines diminish.Exploration to the south-west of the Moomba Field has established the first significant gas flows from rocks beneath the conventional reservoirs of the Cooper Basin. Lycosa-1 drilled a faulted anticline and achieved a maximum gas flow of 5.0 MMCFD (0.14 Mm3/d) from fractured metasiltstone of the Dullingari Group (Ordovician). Moo- lalla-1 drilled a low-side fault terrace and flowed gas at 9.6 MMCFD (0.27 Mm3/d) from 'protoquartzite' tentatively assigned to the Dullingari Group. Consequently, structures where 'basement' reservoirs are faulted against mature Patchawarra Formation source rocks are attractive exploration targets.Petrological studies have identified 'glauconitic illite' in the Cooper Basin sequence suggesting hitherto unrecognised marine conditions. A reassessment of the source and reservoir potential of the region will be necessary if the presence of marine environments is substantiated by further studies.

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