Stratigraphic and structural framework of Himalayan foothills, northern Pakistan

The oldest sedimentary and metasedimentary rocks exposed in the Himalayan foothills of Pakistan record a gradual transition seaward from the evaporites of the Salt Range Formation to pelitic sediments deposited in deeper water to the north. The Upper Proterozoic Tanawal Formation was derived from erosion of a northern highland produced during the early stages of Late Proterozoic to early Ordovician tectonism. Early Paleozoic tectonism is indicated by an angular unconformity at the base of the Paleozoic section, the intrusion of the Mansehra Granite, and the local removal of Cambrian strata. Paleozoic shallow-marine strata are preserved in half-grabens created during extensional tectonism that began during the Carboniferous and climaxed with rifting during the Permian. Paleozoic rocks were largely or completely eroded from northwest-trending highlands on the landward side of the rift shoulder. Thermal subsidence of the rifted margin resulted in transgression of the highlands and deposition of a Mesozoic section dominated by carbonates. Compressional tectonism related to the impending collision with Asia commenced in the Late Cretaceous. Rocks north of the Panjal-Khairabad fault were deformed and metamorphosed during Eocene subduction of northern India beneath the Kohistan arc terrane. Following their uplift and exhumation, rocks metamorphosed beneath Kohistan were thrust southward over unmetamorphosed rocks along the Panjal and Khairabad faults which are inferred to be connected beneath alluvium of the Haripur basin. Contrasts in stratigraphy and metamorphism on either side of the Panjal-Khairabad fault indicate that shortening on this structure exceeds that of any other fault in the foothills region. The migration of deformation towards the foreland produced south- or southeast-vergent folds and thrust faults in strata south of the Panjal-Khairabad fault and reactivated Late Cretaceous structures such as the Hissartang fault. The Hissartang fault is the westward continuation of the Nathia Gali fault, a major structure that thrusts Proterozoic rocks in the axis of a Late Paleozoic rift highland southward over Mesozoic strata. Fundamental differences in stratigraphy, metamorphism, and relative displacement preclude straightforward correlation of faults and tectonic subdivisions of the central Himalaya of India and Nepal with the northwestern Himalaya of Pakistan

Studies in Dye-Tracing Technologies in Karst Hydrogeology

Information on fluorescent dyes used for water tracing and the results of six studies are reported. Optical brightener, direct yellow, fluorescein, rhodamine (WT), and other dyes are described and the procedures employed in their use ·in the field and in equilibration experiments are discussed. Three of the six studies consisted of investigations of the equilibration with passive detectors of three of the dyes. The absorption of optical brightener on fabric detectors was apparently linear with concentration and with immersion time, while detectors became rapidly saturated with direct yellow. Equilibrium of fluorescein on charcoal detectors with an elutriating solution was not achieved. Several data processing tasks were performed, including the creation of a computer file for field data and the writing-of programs to sort the field data and generate plotted maps, and to display the total fluorescence of samples. A fifth study was based. on a series of dye traces into Royal Spring and Russell Cave Spring in the Inner Bluegrass Karst Region. Samples were collected with an automatic water sampler and the resulting flow velocity determinations combined with discharge data provided values at a number of aquifer parameters. The most interesting result was the very small value for depth of flow. A final study was of fracture traces identified on topographic maps and aerial photographs in the Inner Bluegrass Karst Region. It was found that while more such features were visible on the photographs, some were only apparent on maps

Extraordinary transport and mixing of sediment across Himalayan central Gondwana during the Cambrian-Ordovician

Detrital zircon samples from Cambrian and Lower to Middle Ordovician strata were taken across and along the strike of the Himalaya from Pakistan to Bhutan (~2000 km). By sampling rocks from one time interval for nearly the entire length of an orogen, an

Epitope mapping of HSV-1 glycoprotein K (gK) reveals a T cell epitope located within the signal domain of gK

Glycoprotein K (gK) is a virion envelope component of herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), which plays an important role in virion morphogenesis and egress. We previously demonstrated that immunization of mice with gK, but not with any of the ten other HSV-1 glycoproteins, resulted in exacerbation of corneal scarring and herpetic dermatitis following ocular HSV-1 infection. However, little is known about the gK epitope(s) that is (are) involved in T cell activities in vitro or in vivo. Thus, epitope mapping of gK was performed using a panel of 15-mer peptides with five-amino-acid overlaps spanning the full-length gK, and four expressed gK recombinant proteins representing different regions of gK. Epitope mapping within the gK polypeptide defined the amino acid sequence STVVLITAYGLVLVW as the predominant CD4(+) and CD8(+) T cell stimulatory region both in vitro and in vivo. IFN-γ expression by CD4(+) T cells was CD8(+) T cells-dependent. This immunodominant epitope is located within the signal sequence of the gK polypeptide and is highly conserved in HSV-1 and HSV-2 strains. Using prediction algorithms, the peptide is predicted to bind to numerous MHC class I and class II molecules