Wellsville Mountain is 10 miles west of Logan, Utah, at the northern extremity of the Wasatch Range. Paleozoic rocks forma northeast-dipping homocline bounded in part by northwest-trending high-angle faults and cut by a series of northeast-trending high-angle faults. A major transverse fault, with a stratigraphic displacement of 4,500 feet, divides the mountain into two distinct blocks. The rock units of the area are comparable to those of the Logan quadrangle immediately to the east. Pre-Cambrian rocks crop out in Box Elder Canyon, just east of Brigham City, and are overlain by at least 20,000 feet of northeast-dipping Paleozoic rocks of every period except possibly the Permian. The Beirdneau sandstone member of the Jefferson formation, is tentatively correlated with that of the upper Devils Gate limestone of central Nevada. About 6,600 feet of the Oquirrh formation of Pennsylvanian age is exposed near the northern end of Wellsville Mountain. The presence of Desmoinesian fusulinids at the base of the Oquirrh and upper Virgilian fusulinids throughout the interval from 1,000 to 2,000 feet above its base indicates an absence of Lower Pennsylvanian rocks and suggests that the upper 4,400 feet may be in part Permian. Mesozoic rocks are not found in the area. The Wasatch formation and Salt Lake group of Tertiary age crop out in the foothills at the northern end of Wellsville Mountain. Two fault systems are recognized in the area. The northeast-trending high-angle transverse faults of Laramide age and the north-west-trending high-angle bordering faults are Basin and Range age.

Wellsville Mountain forms the extreme northern end of the Wasatch Range in northern Utah. It lies at the western margin of the Middle Rocky Mountain province and is bordered by valleys of the Basin and Range province. Many geologic investigations have been made in this region. Much of the Wasatch Range has been studied and mapped as well as parts of the Bear River Range, east of Cache Valley, and the Malad Range which extends north from Wellsville Mountain; however, the geology of Wellsville Mountain has not been studied or mapped in detail. Some reconnaissance mapping has been done and sections of Cambrian and Pennsylvanian formations have been measured on the western mountain front (Maxey, 1941; Williams, 1943), but little is known about the middle Paleozoic formations and the structural geology of the northern part of the mountain.

Anhydrous ammonia (NH3) was tested as a potential replacement for residual, non specific toxicants as an effective control agent. It was postulated that NH3 would effectively control northern pocket gophers (Thomomys talpoides) and also act as a fertilizer for rangeland vegetation. Compound 1080 was selected as a standard for comparison of gopher control efficiency. Over 700 burrow systems were treated or monitored. Results showed compound 1080 to be 81 percent and NH3 45 percent efficient in controlling gophers. Although fertilizing effects of NH3 were positive, the low control efficiency and high application costs make NH3 an unlikely replacement for the now restricted residual toxicants.

The purpose of this study was to determine the ecological factors existing within the chaparral community. The present status of the vegetation in a one-acre exclosure was analyzed and recorded so that subsequent improvement or eterioration might be noted. A brief history of the area, the weather, and the geology are presented. Many other aspects of the problems enumerated in the introduction need to be studied. This study provides a foundation for a more detailed study of the vegetation which may be undertaken at a future date.

This vegetational analysis is concerned with changes which have cocurred since 1949 in a mountain brush community within an exclosure in the central Wasatch Mountains. The exclosure, established in 1949, is located in Pole Canyon on lower Provo Canyon. Two major studies have been conducted previously, but it has been nine years since the last intensive work was done. Several major changes occurring during the eighteen year period are evident and are described.

This is a comparative study of the vegetation and soils of an exclosure in the mountain brush vegetation of the Wasatch Mountains, Utah. The exclosure was fenced and initially analyzed during the summers of 1949-1950. The study area is located in Pole Canyon in the Uinta National Forest, a few miles northeast of Provo, Utah. The dominant woody species of the vegetation in the exclosure are big toothed maple (Acer grandidentatum) and Gambel oak (Quercus gambelii). After settlement of the area in and around Provo, Pole Canyon became overgrazed by livestock. Since 1949 the area has been protected from grazing. The purpose of this study was to analyze the vegetative and environmental relationships in the exclosure and to determine any changes occurring since the initial study by comparison with the results of the preliminary study.

An analysis of the relative abundance of the prevalent species in 25 major plant communities of the Wasatch Mountains demonstrates that variation in species diversity is significantly correlated with many floral characteristics. Wind pollinated flowers decrease in abundance while animal pollinated flowers increase along the diversity gradient. Both relationships are highly significant statistically. Color diversity and species diversity are significantly and positively correlated in open communities but are not correlated in forest communities. The percent sum frequency of yellow and pink-magenta flowers decreased with increasing species diversity while blue and whitish flowers increased. Also, zygomorphic flowers and flowers in which access to the nectar supply is restricted by morphological barriers are positively correlated with species diversity. It is shown that wind pollinated flowers and entomophilous open flowers are significantly more abundant than animal pollinated flowers whose nectaries are morphologically restricted, Theoretical explanations are offered for these relationships.

A detailed structural study of Rock Canyon (near Provo, Utah) provides insight into Wasatch Range tectonics and fold-thrust belt kinematics. Excellent exposures along the E-W trending canyon allow the use of digital photography in conjunction with traditional field methods for a thorough analysis of Rock Canyon's structural features. Detailed photomontages and geometric and kinematic analyses of some structural features help to pinpoint deformation mechanisms active during the canyon's tectonic history. Large-scale images and these structural data are synthesized in a balanced cross section, which is used to reconstruct the structural evolution of this portion of the range. Projection of surficial features into the subsurface produces geometrical relationships that correlate well with a fault-bend fold model involving one or more subsurface imbrications. Kinematic data (e.g. slickenlines, fractures, fold axes) indicate that the maximum stress direction during formation of the fault-bend fold trended at approximately 120°. Following initial thrusting, uplift and development of a thrust splay produced by duplexing may have caused a shift in local stresses in the forelimb of the Rock Canyon anticline leading to late-stage normal faulting during Sevier compression. These normal faults may have activated deformed zones previously caused by Sevier folding, and reactivated early-stage decollements found in the folded weak shale units and shaly limestones. Movement on most of these normal faults roughly parallels stress directions found during initial thrusting indicating that these extensional features may be coeval with thrusting. Other zones of extension and brittle failure produced by lower ramp geometry appear to have been activated during Tertiary Basin and Range extension along the Wasatch Fault Zone. Slickenline data on these later normal faults suggest a transport direction of nearly E-W distinguishing it from earlier events.

The Early Pennsylvanian (Bashkirian/Morrowan) Bridal Veil Limestone of north-central Utah was deposited in the eastern portion of the rapidly subsiding Oquirrh basin. The 420 meter-thick Bridal Veil Limestone displays distinct cyclicity formed by stacked, meter to decameter scale high-frequency sequences and their constituent parasequences. Though no one ideal cycle may be defined for the Bridal Veil Limestone, each high-frequency sequence and parasequence contains a general shallowing upward trend that ranges from anaerobic to dysaerobic mudstone at the base to skeletal wackestone to mud-dominated packstone, capped by heterozoan grain-rich carbonates or siliciclastic tidalites. Cycles bounded by exposure surfaces, indicated by micro-brecciation, rhizoliths, laminated calcite or silica crusts, rip-up clasts, centimeter-scale teepee structures, and/or pronounced erosional relief are termed high-frequency sequences. Those bounded by marine flooding surfaces are defined as parasequences. Thusly defined, the Bridal Veil Limestone is divided into 25 high-frequency sequences designated BVL-1 through BVL-25. Overall, two distinct sets of high-frequency sequences may be observed in the Bridal Veil Limestone. Sequences comprising the lower half of the formation (BVL-1 through BVL-12) are thicker, muddier, and less sand-prone than sequences in the upper half of the formation (BVL-13 through BVL-25), indicating an overall change in oxygenation, depositional texture, and accommodation upward in the section. Tracing of key beds and surfaces between the Thorpe Hills, Lake Mountain, and the Wasatch Range (spanning a distance greater than 50 miles) reveals that deposition was remarkably uniform across the southeastern part of the Oquirrh basin which we herein designate the Bridal Veil sub-basin and distinct from coeval formations in the southern Oquirrh basin, Ely basin, and Wyoming shelf. Mudstone and wackestone textures comprise a large portion of the formation by volume. Grain-rich carbonates are almost exclusively heterozoan in composition, indicating that the sub-basin was subphotic to aphotic through Early Pennsylvanian time.