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The Farmington Canyon Complex, situated along the Wasatch front in northern Utah, has been the target for many studies. The FCC has been interpreted to be a passive margin sedimentary wedge. Previous studies have yielded isotopic ages that broadly support an Archean age of formation, and a prominent mid-proterozoic amphibolite grade metamorphic event. Based on this study, a new interpretation for the FCC is presented. Field relations and whole-rock geochemistry as well as recent advances in understanding Archean crustal processes have resulted in the FCC to be considered as an accretionary complex that formed along the SW margin of the Wyoming province in the early Archean. Rock assemblages such as mafic and ultramafic metavolcanics have chemistries that resemble oceanic crust and arc related volcanics. The extensive quartzo-felspathic gneiss and schist units have compositions that reflect greywacke, and are presented here as a melange matrix. The quartzites have chemistries, which may represent cherts or silicified microbial mats. The field relations and timing of these rocks indicate that the FCC may represent a continental arc synchronous with the closing of an ocean basin, forming an accretionary wedge. This culminated with the mid-proterozoic metamorphic event as this continental arc collided with the Santaquin arc, as well as the SW margin of Laurentia. This amphibolite grade metamorphic event has subsequently reset or overprinted isotopic evidence and obscured any textures that may have existed. Although much has yet to be learned about Archean processes, comparison to other recognized Archean accretionary complexes has yielded striking similarities, and it is presented here that the FCC represents an active margin, and is likely an accretionary melange.

The Weston Canyon area comprises the southern part of the Bannock Range and northwestern part of the Malad Range in southern Idaho. Geologic investigations of adjacent areas date from 1871. These investigations have led to detailed geologic reports that cover much of the Wasatch Range, Bear River Range, Malad Range, Portneuf Range, and Cache Valley. The geology of the southern part of the Bannock Range, however, has not been studied in detail, and it is the purpose of this investigation to map and describe the geology of the Weston Canyon area and to correlate it with previously described geology of the region.

General Statement A detailed study of the southwestern part of the Randolph quadrangle was undertaken in view of the fact that Richardson (1941) mapped a large area of undifferentiated Ordovician rock. Therefore, the purposes of this investigation are: (1) to prepare a more detailed geologic map of the south­western part of the Randolph quadrangle (Plate 1), (2) to describe the struc­ture, stratigraphy, and geologic history of the area, and (3) to relate the geology to adjacent areas. The elevation of the area mapped ranges from approximately 8, 910 to 6, 700 feet above sea level with the major part of the area above 8, 000 feet. This area forms part of the eastern ridge of the Bear River Range (Williams, 1948, p. 1, 125-1, 126). The southern boundary of the area extends east from the southwest corner of the Randolph quadrangle for a distance of about 4 miles. The eastern boundary extends northward about 11 miles and is parallel to the mountain front. The northern boundary is less well defined and is taken as the ridge separating Curtis Creek from the next canyon to the north. The western boundary extends south approximately 10 miles to the southwest corner of the Randolph quadrangle. The southwestern part of the Randolph quadrangle (Figure 1) covers approximately 56 square miles and lies approximately 60 per cent in Cache County and 40 per cent in Rich County. The major part of the area lies within the Cache National Forest. The area mapped is generally accessible from mid-June to mid- September. A road is maintained along the length of the area by the U. S. Forest Service and is passable by automobile except during heavy rain- storms in the summer months. Field Work The field work was done during the summer of 1963. Formation con- tacts, attitudes, and faults were mapped in the field on aerial photographs of the approximate scale 1:20, 000. This information, concerning the south- western part of the Randolph quadrangle, was transferred to a base map constructed from the topographic map of the U. S. Geological Survey of the same area (1912 edition). The base map was enlarged to the scale 1:24, 000. Stratigraphic sections were measured with a 50-foot steel tape. A Brunton compass was used to measure attitudes and slope angles. Sample rock types were collected from each unit and compared with the rock-color chart (Goddard, 1951) to obtain standard color names. Fossils were collected and identified in the laboratory by the author. Previous Investigations The earlier geologic reports from the general area of the Randolph quadrangle are found in the Hayden Survey and the survey of the Fortieth Parallel supervised by King. Hayden (1871, p. 150-156), Peale (1877, p. 573-609), Hague (1877, p. 393-442), and Emmons (1877, p. 326-393) all commented upon the general area. Walcott (1908) studied the Cambrian rocks of the Bear River Range and defined eight formations. Veatch (1907) studied the area adjacent to the Randolph quadrangle in Wyoming. In the Randolph quadrangle, Richardson (1913) divided the Ordovician rocks into three formations, identified the Silurian rocks as a formation, defined one Mississippian formation, and later (1941) published a geologic map of the quadrangle. Mansfield's (1927) study of southeastern Idaho provided valu­able information concerning regional structure and stratigraphy. Williams (1948) mapped the Logan quadrangle which is adjacent to the area on the west. Specific studies (Ross, 1949, 1951; Maxey, 1941, 1958) have given more detailed information concerning Cambrian and Ordovician rocks of the area. A recent publication by Armstrong and Cressman (1963) is important in dating the uplift and thrust faulting in the ancestral Bear River Range. The Geologic Map of Utah (Stokes, 1961) followed the interpretaion of Richardson (1941), for the southwestern part of the Randolph quadrangle, except in the designation of the Wasatch formation which is shown as Knight conglomerate.

This study investigates the hydrodynamic variations along the Gao-ping Submarine Canyon influence by the topography effects. The data used in this study were collected from two cruises of field observations using research vessel OR3. Instruments applied include sb-ADCP¡Bbm-ADCP¡Bmoored-ADCP¡BCTD and several vertical strings of temperature loggers. Parameters recorded include flow velocities, water temperature and tidal elevation. The analysis method is enlightenment by the case study in the Monterey Canyon of California. The results show that (1) the current speed in the lower layer is faster than that of upper layer, which is explained due to v-shape of topography and bottom-trapped effect of internal tide. This result is consistent with previous studies. (2) In flood tide, the currents flowed into the Canyon from deep water to shallower. The baroclinic kinetic energy decreased to 0.2 at the turning point of canyon axis at 230m water, whichwas caused mainly by bottom friction. On the other hand, the baroclinic kinetic energy increased to 0.47 at 250m water in ebb tide when there was less influence of bottom friction. (3) In comparison the effects of bottom slope and area of cross section of the canyon, the baroclinic kinetic energy dissipation was mainly occurred at up slope flow during the flood tide. The change of the canyon width had less influence. During the ebb, the baroclinic kinetic energy was mainly due to the change of canyon width in the region shallower then the 230m of the second turning of the canyon. (4) The loss of kinetic energy during flooding up slope current can be verified by the changes of water mass temperature. Cold bottom was raised to upper layer when there was large drop of kinetic energy. There was likely a conversion of kinetic energy to potential energy. No upwelled cold water detected during ebb current with increase of kinetic energy.

Internal tide is generated in the interface of density stratification by some hydrodynamic disturbance. The major mechanisms are borotrophic tidal current oscillated at the edge of the continental shelf, submarine canyons, ridges or sills. The resulting disturbance generated has the same motion cycle of tidal period. There were internal tides reported in the Kaoping Submarine Canyon. The generation sites and mechanisms, however, are not clear. This study analysis four cruises of field observed data using ship mounted ADCP and CTD, and moored temperature strings and current meters. The results showed: (1) The phase of M2 tidal current increase toward the canyon head, with minimum value at the canyon mouth. This result implies that the internal tide was generated near the canyon mouth and propagated up canyon with the thermocline decreasing toward the shallower water. (2) The internal tide generated at the canyon mouth propagated, through some mechanisms, at the upper layer density interface about 150m instead of beaming near the bottom layer where the current and topography interact. (3) The vertical variations of tidal ellipse and phase based on bottom mounted ADCP support the results of ship mounted observations, the internal tidal energy propagates near the interface of 150m below the surface.

A field study of positive inversion is conducted to describe associated structural fabrics and to infer kinematic development of the Palisades Monocline, Grand Canyon, Arizona. These features are then compared to sand, clay and solid rock models of positive inversion to test model results and improve understanding of inversion processes. The N40W 90 oriented Palisades fault underlying the monocline has experienced northeast-southwest Precambrian extension and subsequent northeastsouthwest Laramide contraction. The magnitude of inversion is estimated to be 25% based on vertical offset across the fault, although this does not account for flexure or horizontal shortening. The preferred N50W 90 joint and vein orientation and N50W 68 NE and SW conjugate normal faults are consistent with the Palisades fault and northeastsouthwest extension. The N45E 90 joint orientation and approximately N40W 28 NE and SW conjugate thrust faults are consistent with northeast-southwest contraction. The deformation is characterized by three domains across the fault zone: 1) the hanging wall, 2) the footwall, and 3) an interior, fault-bounded zone between the hanging wall and footwall. Extensional features are preserved and dominate the hanging wall, contractional features define footwall deformation, and the interior, fault-bounded zone is marked by the co-existence of extensional and contractional features. Extension caused a master normal fault and hanging wall roll-over with distributed joints, veinsand normal faults. During inversion, contraction induced reverse reactivation of existing hanging wall faults, footwall folding and footwall thrust-faulting. Precambrian normal slip along the master normal fault and subsequent Laramide reverse slip along the new footwall bounding fault created an uplifted domain of relatively oldest strata between the hanging wall and footwall. Physical models of co-axial inversion suggest consistent development of the three domains of deformation described at the Palisades fault, however the models often require magnitudes of inversion greater than 50%. Although vertical block motion during horizontal compression is not predicted directly by the Mohr-Coulomb criterion, physical models and analytical solutions (incorporating Mohr- Coulomb criterion) suggest maximum stress trajectories and near vertical failure above high angle basement faults that compare favorably with the Palisades fault zone.

This study presents the first reconstruction of pollution history of Polychlorinated biphenyls (PCBs) in Taiwan coast. Six sediment cores were collected from Gaoping submarine canyon and its adjacent area to investigate the distribution and source recognition of PCBs. The concentrations of PCBs in the cores from Gaoping canyon ranged 0.155--2.281 ng/g dry wt, whereas the maximum concentrations of PCBs reached 21.0 and 2.93 ng/g dry wt, respectively, in the cores from the northern and sourthern continental shelf of Gaoping canyon. The toxicological effects assessed by sediment quality guidelines (SQGs), show that only 2-10cm in core L27 exceeded the guideline value suggested by Förstner (6 ng/g), which indicated the sediment in this area had been polluted seriously and should not be disturbed. Overall, compared with studies in the world, the sediment PCB concentrations in Kao-Ping coastal areas were relatively low. Hierarchical Cluster Analysis identified the source of PCBs in the study area was a mixture of Aroclor 1016, Aroclor 1242 and Aroclor 1260. Similarity in vertical variations of total concentrations of PCBs among the six cores was observed and the trend is consistent with the history of the PCB usage in Taiwan. The drastic decrease in PCB concentrations around the late 1980s, clearly demonstrates the effectiveness of the ban of PCBs use in 1980 in Taiwan.

This study was designed to inform the third party Environmental Impact Statement (EIS) required for the Quitchupah Creek Road, UTU-57907, Fishlake National Forest and Bureau of Land Management, Richfield District, Sevier and Emery Counties, Utah. The road proposal involved upgrading a jeep trail located in Quitchupah Canyon. Modifications of this four-wheel drive dirt road would involve extensive environmental engineering, bridges culverts for side canyon intermittent streams and paving of approximately 9.2 miles. A team of ethnographers from the University of Arizona interviewed members of the Paiute Indian Tribe of Utah (PITU) to understand cultural meaning, traditional use, and potential impacts to Native American resources in the study area.