Northwest Arizona Research Articles

Characterizing fungal communities on Mojave desert tortoises (Gopherus agassizii) in Arizona to uncover potential pathogens

The Mojave Desert tortoise (Gopherus agassizii) is a threatened reptile endemic to the southwestern United States. There are many factors contributing to its population decline such as human-driven habitat destruction and infectious diseases, which might include emerging fungal pathogens. We analyzed the fungal communities of two tortoises from northwest Arizona and compared the host mycobiome to the burrow mycobiome. Our main goal was to characterize the fungal community living on the Mojave Desert tortoise and to determine whether there are differences in community composition and potential pathogen abundance between the soil from burrows and tortoises’ mycobiome. Dissimilarities in communities would indicate that there are fungi adapted to the animal niche that are rarely present in soil and vice versa. Metagenomic analysis of ITS2 amplicons revealed significant differences in fungal communities between the substrate and samples taken from the animals. The tortoise samples show higher alpha diversity than the soil and are distinct from soil samples based on beta diversity analysis. We observed significantly greater relative abundance of potential fungal pathogens from the order Onygenales in the tortoise samples than the soil. These mycobiome data suggest that there is a unique fungal community occupying the desert tortoise host niche and this community contains a higher relative abundance of potential fungal pathogens. We argue that these fungi may pose a risk for increased morbidity and mortality among desert tortoises, which can in turn drive population decline.

Microbiome of Grand Canyon Caverns, a dry sulfuric karst cave in Arizona, supports diverse extremo-philic bacterial and archaeal communities

We analyzed the microbial community of multicolored speleosol deposits found in Grand Canyon Caverns, a dry sulfuric karst cave in northwest Arizona, USA. Underground cave and karst systems harbor a great range of microbial diversity; however, the inhabitants of dry sulfuric karst caves, including extremophiles, remain poorly understood. Understanding the microbial communities inhabiting cave and karst systems is essential to provide information on the multidirectional feedback between biology and geology, to elucidate the role of microbial biogeochemical processes on cave formation, and potentially aid in the development of biotechnology and pharmaceuticals. Based on the V4 region of the 16S rRNA gene, the microbial community was determined to consist of 2207 operational taxonomic units (OTUs) using species-level annotations, representing 55 phyla. The five most abundant Bacteria were Actinobacteria 51.3 ± 35.4 %, Proteobacteria 12.6 ± 9.5 %, Firmicutes 9.8 ± 7.3 %, Bacteroidetes 8.3 ± 5.9 %, and Cyanobacteria 7.1 ± 7.3 %. The relative abundance of Archaea represented 1.1 ± 0.9 % of all samples and 0.2 ± 0.04 % of samples were unassigned. Elemental analysis found that the composition of the rock varied by sample and that calcium (6200 ± 3494 ppm), iron (1141 ± 1066 ppm), magnesium (25 ± 17 ppm), and phosphorous (37 ± 33 ppm) were the most prevalent elements detected across all samples. Furthermore, carbon, hydrogen, and nitrogen were found to compose 4.7 ± 4.9 %, 0.3 ± 0.4 %, and 0.1 ± 0.1 % of samples, respectively. Finally, Raman spectra compared to the RRUFF Project database using CrystalSleuth found that the mineral composition of the speleosol consisted of calcite, hematite, paraspurrite, quartz, and trattnerite. These data suggest that dry sulfuric karst caves can harbor robust microbial communities under oligotrophic, endolithic, and troglophilic conditions.

Emergence of the Leaf Beetle Triarius trivittatus (Coleoptera: Chrysomelidae) from Sacahuista Nolina microcarpa (Asparagaceae)

Nolina microcarpa S. Watson (Asparagaceae) shrubs in northwest Arizona were covered with insect-emergence traps to determine whether Triarius trivittatus Horn (Coleoptera: Chrysomelidae), a beetle species that carries pollen from male to female flowers, undergoes larval development on the plant. The 3 traps covered different clumps of leaf rosettes and caught 39 beetles, 15 males and 24 females, during 27 May–24 June 2019. Larvae of T. trivittatus likely develop on roots, similar to other beetles in the same tribe, or on underground stems that connect leaf rosettes. Development of larvae on the plant, as well as pollen transport to female flowers by the adult beetles, suggests that N. microcarpa and T. trivittatus have a mutualistic relationship.

The Colorado and Virgin Rivers before Lake Mead

ABSTRACTIn 1936, the completion of Hoover Dam on the Colorado River in Nevada and Arizona created Lake Mead, the largest reservoir in the United States. When the lake reached capacity in 1941 several canyons and valleys were flooded, along with two towns, several mines, farm fields, and roads. The area had not been surveyed archaeologically and little detailed information exists about the vegetation and geology of this region. The map reconstructions the geography of the area in 1930 before Lake Mead was constructed, showing roads, towns, mines, physical features, and private property, and was created using a range of historical United States Geological Survey (USGS) maps, a digital elevation model (DEM) providing underwater elevations, and other historical sources. The map includes portions of southern Nevada and northwest Arizona, United States, and is at a scale of 1:210,000. It is hoped that the map may draw attention to the lost geographies of other localities across the United States due to the more than 84,000 dams and reservoirs in the country.

A Brief Evaluation of a Project to Engage American Indian Young People as Agents of Change in Health Promotion Through Radio Programming, Arizona, 2009-2013.

Young people can be valuable motivational resources for health promotion. A project implemented from 2009 through 2013 in a small American Indian community in northwest Arizona recruited American Indian young people aged 10 to 21 as agents of change for health promotion through radio programming. Thirty-seven participants were recruited and trained in broadcasting and creative writing techniques; they produced and aired 3 radio dramas. In post-project evaluation, participants were confident they could influence community behaviors but thought that training techniques were too similar to those used in school activities and thus reduced their drive to engage. Effective engagement of young people requires creativity to enhance recruitment, retention, and impact.

Paleogene Grand Canyon incompatible with Tertiary paleogeography and stratigraphy

The Hualapai Plateau in northwest Arizona, the location of the western Grand Canyon, contains an unusually lengthy Tertiary stratigraphic record dominated by fluvial deposition and extending from at least late Paleocene through late Miocene time. The thickest and oldest Tertiary sections are best exposed in a system of partially re-exhumed Laramide paleocanyons. The Paleogene drainage system was locally disrupted and ponded by Laramide monoclines. In pre-Oligocene time, extensive alluvial fans spread southward from the Shivwits Plateau scarp across the current location of the modern Colorado River gorge to the northern margin of the Laramide drainage system at Hindu Canyon. Locally derived, fluvial Buck and Doe Conglomerate subsequently filled the disrupted Paleogene channels, spilled out over the local interfluves, and formed an extensive aggradational surface of low relief by late Oligocene time. Early Miocene volcanism filled in much of the relict Laramide relief. Erosional recession of the adjacent Shivwits Plateau escarpment shifted the northern Hualapai Plateau margin 8 km northeastward after the Laramide drainage episode and before the incision by the modern Colorado River. Partially exhumed tributaries to the Hindu Canyon paleochannel and associated sedimentary deposits bordering the southern edge of the Grand Canyon gorge demonstrate that local surface runoff flowed south, away from the modern Grand Canyon location, during early Paleogene time. Headwardly eroding Colorado River tributaries exhumed, captured, and reversed the flow of these tributaries to the Laramide canyon, beginning in late Miocene or Pliocene time. The geomorphic and stratigraphic records show no evidence of, and provide no space for, incision of a Late Cretaceous–Paleogene ancestral precursor to the modern Colorado River gorge. Instead, all the field evidence clearly supports a late Miocene–Pliocene origin for integration of the western Grand Canyon on the central Hualapai Plateau with the upper Colorado River.

Parasitism of Prehistoric Humans and Companion Animals from Antelope Cave, Mojave County, Northwest Arizona

Previously, we reported a tick recovered from Antelope Cave in extreme northwest Arizona. Further analyses of coprolites from Antelope Cave revealed additional parasitological data from coprolites of both human and canid origin. A second tick was found. This site is the only archaeological locality where ticks have been recovered. We also discovered an acanthocephalan in association with Enterobius vermicularis eggs in the same coprolite. This association shows that the coprolite was deposited by a human. This discovery expands our knowledge of the range of prehistoric acanthocephalan infection. In addition, findings from canid coprolites of Trichuris vulpis are reported. This is the first published discovery of T. vulpis from a North American archaeological context. The close association of dogs with humans at Ancestral Puebloan (Anasazi) sites raises the potential that zoonotic parasites were transferred to the human population. The archaeological occupation is associated with the Ancestral Pueblo culture 1,100 yr ago.

A Tick From a Prehistoric Arizona Coprolite

Ticks have never been reported in archaeological analyses. Here, we present the discovery of a tick from a coprolite excavated from Antelope Cave in extreme northwest Arizona. Dietary analysis indicates that the coprolite has a human origin. This archaeological occupation is associated with the Ancestral Pueblo culture (Anasazi). This discovery supports previous hypotheses that ticks were a potential source of disease and that ectoparasites were eaten by ancient people.

MORTALITIES FROM CLIMBING ACCIDENTS OF TRANSLOCATED BIGHORN SHEEP IN ARIZONA

Abstract Desert bighorn sheep (Ovis canadensis) are known for their climbing skills in rugged and steep terrain. Occasionally sheep die from climbing accidents. Between 1979 and 1995, the Arizona Game and Fish Department reintroduced desert bighorn sheep to areas within their historic distribution: northwest, southwest, southeast, and central Arizona. Because at least half of reintroduced sheep (n = 412) were fitted with radiocollars and monitored monthly, we documented mortalities by climbing accidents. None of 54 mortalities in the southeastern region and 53 mortalities in the southwestern region was identified as climbing accidents. However, climbing accidents caused 5 of 42 sheep mortalities in the northwestern region and 4 out of 54 mortalities in the central region. Most climbing accidents (7 out of 9) happened <9 months after sheep were translocated. Our data suggest that translocated desert bighorn sheep can be vulnerable to climbing accidents due to lack of familiarity with local terrain. Differe...

Effects of historical mining activities on surface water and groundwater - an example from northwest Arizona

The focus of this research was to determine the impact of abandoned mines on surface water and groundwater in the historical mining districts of the Cerbat Mountains, Arizona. The surface water in the mining areas was found to be contaminated by various combinations and concentrations of heavy metals. Elevated arsenic, cadmium, and iron concentrations were detected in most surface-water samples, while lead, copper, and zinc contamination differed from region to region, depending on the ore mined. The groundwater was seriously polluted by arsenic, cadmium, lead, zinc, iron, and manganese in the immediate vicinity of mines that processed ore on the site, such as the Tennessee Mine near Chloride. Chloride's groundwater, however, showed no evidence of contamination. Three possible explanations are discussed: immobilization of the heavy metals in the soil by chemical reactions and adsorption, dilution effects due to the rainy season in spring, or the existence of different groundwater systems.

Pattern of Herbivore Abundance Along a Climatic Gradient: Guild Shift of Leaf-Feeding Insects and Changes in Leaf Characteristics

The abundance of insects in 3 feeding guilds (strip-feeding, pit-feeding, and sucking) and leaf characteristics (toughness as measured by resistance to penetration, and specific leaf area) were examined during 2 summers along a climatic and vegetation gradient in the southwest United States. Strip-feeding insects were more abundant, and needles were softer (less resistant to penetration) and thinner (higher specific leaf area) on pinon pines of summer-wet southeast Arizona than on pinon pines of the drier summer climates of northcentral and northwest Arizona. Sucking insects were more abundant and needles were tougher on pinon pines of northcentral Arizona. Pit-feeding insects were less abundant on southeast pinon pines (the difference was significant in 1990 but not 1991) and showed different abundance on northcentral and northwest pinon pines between the 2 summers.

Crustal structure of the Colorado Plateau, Arizona: Application of new long‐offset seismic data analysis techniques

The Colorado Plateau is a large crustal block in the southwestern United States that has been raised intact nearly 2 km above sea level since Cretaceous marine sediments were deposited on its surface. Controversy exists concerning the thickness of the plateau crust and the source of its buoyancy. Interpretations of seismic data collected on the plateau vary as to whether the crust is closer to 40 or 50 km thick. A thick crust could support the observed topography of the Colorado Plateau isostatically, while a thinner crust would indicate the presence of an underlying low‐density mantle. This paper reports results on long‐offset seismic data collected during the 1989 segment of the U.S. Geological Survey Pacific to Arizona Crustal Experiment that extended from the Transition Zone into the Colorado Plateau in northwest Arizona. We apply two new methods to analyze long‐offset data that employ finite difference travel time calculations: (1) a first‐arrival time inverter to find upper crustal velocity structure and (2) a forward‐modeling technique that allows the direct use of the inverted upper crustal solution in modeling secondary reflected arrivals. We find that the crustal thickness increases from 30 km beneath the metamorphic core complexes in the southern Basin and Range province to about 42 km beneath the northern Transition Zone and southern Colorado Plateau margin. We observe some crustal thinning (to ∼37 km thick) and slightly higher lower crustal velocities farther inboard; beneath the Kaibab uplift on the north rim of the Grand Canyon the crust thickens to a maximum of 48 km. We observe a nonuniform crustal thickness beneath the Colorado Plateau that varies by ∼15% and corresponds approximately to variations in topography with the thickest crust underlying the highest elevations. Crustal compositions (as inferred from seismic velocities) appear to be the same beneath the Colorado Plateau as those in the Basin and Range province to the southwest, implying that the plateau crust represents an unextended version of the Basin and Range. Some of the variability in crustal structure appears to correspond to preserved lithospheric discontinuities that date back to the Proterozoic Era.

The active southwest margin of the Colorado Plateau: Uplift of mantle origin

During Cenozoic time, the Colorado Plateau was raised about 2 km above sea level. The most-recent and best-documented uplift of the plateau (;1 km) has been concentratedatitssouthwestmarginbetween6 and 1 Ma, whereas the eastern Colorado Plateau may have been at high elevations sinceEocenetime.Tobetterunderstandthe recent tectonic activity at the southwest marginoftheColoradoPlateau,wecompile detailed crustal thickness and density informationfromseismicandgravitydatafor a region that includes northwest Arizona and the southern tip of Nevada. This information is used to isolate the mantle contribution to uplift. Wefind that there is relatively low density mantle underlying the southernmarginoftheplateauinnorthwest Arizona, which could result from about 60‐80 km of thinning of the dense mantle lithosphere combined with about 100 &Cof heating through a 100-km-thick mantle layer. The available estimates from earthquake-source seismology in or near the studyareaarecompatiblewiththisestimate of lithospheric thinning. We speculate that uplift may result from subduction-related thinning of the continental lithosphere.

Patterns of food use and nutrient intake of obese and non-obese Hualapai Indian women of Arizona

To document patterns of food use and nutrient intake associated with obesity in Native American women, a sample of 14 obese and 14 non-obese free-living Hualapai Indian women living in northwest Arizona was studied. Patterns of food use were determined through long-term observation, dietary histories, and 24-hour dietary recalls. Dietary intake was determined through 24-hour dietary recalls over 7 consecutive days. Patterns of food acquisition, selection, and preparation were similar for obese and non-obese Hualapai women. The diets of both groups were dominated by nonalcoholic beverages, potatoes, beans, white wheat flour, and canned goods. Wild and locally cultivated foods were not eaten on a regular basis. The diets of both the obese and non-obese women were high in energy (pooled mean +/- standard deviation [SD] = 2,602 +/- 766 kcal/day) and carbohydrates (pooled mean +/- SD = 333.4 +/- 95.6 gm/day), moderate in protein (pooled mean +/- SD = 77.8 +/- 20.9 gm/day) and fat (pooled mean +/- SD = 101.1 +/- 25.4 gm/day), and low in crude fiber (pooled mean +/- SD = 4.7 +/- 2.0 gm/day). The study indicates that significantly (p less than .001) higher energy intakes of the obese women can be attributed to their greater consumption of nonalcoholic and alcoholic beverages.

Preliminary Petroleum Source Rock Assessment of Upper Proterozoic Chuar Group, Grand Canyon, Arizona: ABSTRACT

Strata in the Chuar Group, Grand Canyon, Arizona, are potential petroleum source rocks. This group, divided into the Galeros Formation below and the Kwagunt Formaton above, consists predominantly of very fine-grained siliciclastic rocks and thin sequences of sandstones and stromatolites and cryptalgal carbonate rocks. Over half the succession consists of organic-rich, gray to black mudstone and siltstone. Geochemical analyses indicate that the 281-m thick Walcott Member, the uppermost unit of the Kwagunt, has good to excellent petroleum source rock potential. The lower half of the Walcott is characterized by total organic carbon (TOC) contents as much as 7.0% (average /approximately/ 3.0%), hydrogen indices as much as 204 mg HC/g TOC (average 135 mg HC/g TOC), genetic potentials (S/sub 1/ + S/sub 2/) of nearly 16,000 ppm (average /approximately/ 6000 ppm), and extractable organic matter (EOM) as much as 4000 ppm. Data for the upper Walcott are incomplete but suggest that these rocks are as rich or richer than the lower Walcott. Maturity assessment indicates that source rocks of the Walcott are within the oil generation window. Strata of the thermally mature underlying Awatubi Member of the Kwagunt and the thermally mature to overmature Galeros Formation are, in general, rated asmore » poor oil sources with genetic potentials generally less than 1000 ppm, but they are possible gas sources. Several thin sequences in these units, however, display good oil source characteristics, with EOM nearly 2000 ppm and genetic potentials nearly 7000 ppm. Chuar Group strata may be potential sources for economical accumulations of petroleum in upper Proterozoic or lower Paleozoic reservoir rocks in northwest Arizona and southwest Utah.« less

Integrated analysis of high-resolution field and airborne spectroradiometer data for alteration mapping

Oatman epithermal gold deposit in Northwest Arizona. Pervasive argillic and wall-rock phyllic and propylitic alteration. Discrimination of these zones rests on identification of the dominant alteration minerals; alunite, illite (mica), and chlorite.--Modified journal abstract.

Scapolite phenocrysts in a latite dome, northwest Arizona, U.S.A.

A latite dome in northwest Arizona contains a rare occurrence of primary SO 4-rich scapolite phenocrysts. The total phenocryst assemblage consists of plagioclase (An 20−An 33), hornblende, biotite, and scapolite (Me 68). Microphenocrysts include allanite and oxidized low-Ti magnetite. Electron microprobe analyses show that the scapolite contains about 1.74 wt.% S, which indicates an atomic S/(S + C) of 0.58. Although scapolite occurs in xenoliths in volcanic rocks and diatremes, as well as a metamorphic mineral in granulites, its occurrence as a primary igneous mineral is extremely rare. Ca-rich scapolite has been crystallized experimentally by others from melts with a wide range of SiO 2, CaO, and Na 2O contents, at temperatures above 825°C and pressures ranging from 3 to 15 kbar. Comparison of scapolite from this latite with synthetic scapolite crystallized from nepheline syenite melt suggests that the Arizona phenocrysts crystallized under conditions of 850 to 900°C, 3–6 kbar total pressure, and unusually high ƒ CO 2 and ƒ SO 2 . The rarity of scapolite as a phenocryst mineral suggests that high partial pressures of CO 2 and SO 2 are rare in the magmatic environment.

A regional strategy for geothermal exploration with emphasis on gravity and magnetotellurics

As part of the resource evaluation and exploration program conducted by Los Alamos Scientific Laboratory for the national Hot Dry Rock (HDR) Geothermal Program, a regional magnetotelluric (MT) survey of New Mexico and Arizona is being performed. The MT lines are being located in areas where the results of analysis of residual gravity anomaly maps of Arizona and New Mexico, integrated with other geologic and geophysical studies indicate the greatest potential for HDR resources. The residual gravity anomalies are derived by applying the concept of predicting gravity anomalies from topography. This can be accomplished by employing reductions similar to those used in some isostatic investigations, in which a regional topographic surface is used as the Bouguer reduction datum. The datum is derived by comparison of various harmonics of Bouguer anomalies and elevations of stations. Topography can be used to predict Bouguer anomalies because of isostatic compensation; the resultant anomalies can be considered high frequency residual anomalies or isostatic anomalies corrected for regional compensation. Such maps have been produced for Arizona, New Mexico, west Texas, and Chihuahua, Mexico. The main objective of the MT project is to produce a regional geoelectric contour map of the pervasive deep electrical conductor within the crust and/or upper mantle beneath the Colorado Plateau and the adjacent Basin and Range Province and Rio Grande Rift. The MT survey consists of 200 sites along several long profiles with site spacing of 15–20 km. Pre-existing available MT data are being integrated with the new data. After the data are processed, a one-dimensional inversion is applied to the sounding curve and used as a starting point for 2-D modeling. Such a project and ultimate map will be of major value in studying the regional geophysics and tectonics of the southwest United States as they now apply to HDR resources in particular and geothermal resources in general. Electrical conductivity anomalies of large areal extent are of particular interest in geothermal exploration. Correlation analysis of large conductive anomalies with other geophysical, geological, and geotectonic data is being performed. Preliminary analysis of the data has suggested several major regions of anomalously shallow high electrical conductivity. Among these is the Aquarius area of northwest Arizona which is the site of a longwavelength residual anomaly low, which when modeled and correlated with other geophysical data can be shown to be possibly related to low density and high temperature in the crust at depths of 20 km or less. Preliminary analysis of MT data indicates the possible existence of a mid-crustal high electrical conductivity anomaly in this same region.

Analysis of Arizona Flood Data Network for regional information

The technique known as Network Analysis for Regional Information is used for a network of stream‐gaging stations in northwest Arizona in order to suggest a logical gaging strategy for the area. This procedure uses a Bayesian estimation scheme to arrive at the relationship between information content of a regional regression and the level of data availability (measured by the number pf stations and harmonic mean record length). Superimposed on this relationship is the relationship between estimated network operating costs for planning periods of 10, 20, and 30 years for alternative gaging strategies. These relationships are used to develop the relationship between expected information content of the network and estimated cost of network operation, which, in turn, can be used to suggest the best gaging strategy to pursue in an uncertain future.

A Regional Seismic Evaluation of Flagstaff, Arizona

Research Article| January 01, 1977 A Regional Seismic Evaluation of Flagstaff, Arizona SALVATORE GIARDINA, JR. SALVATORE GIARDINA, JR. At the time of this writing, Salvatore Giardina, Jr. was with Engineers Testing Laboratories, Inc., Phoenix, Arizona. Search for other works by this author on: GSW Google Scholar Environmental & Engineering Geoscience (1977) xiv (2): 89–103. https://doi.org/10.2113/gseegeosci.xiv.2.89 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation SALVATORE GIARDINA; A Regional Seismic Evaluation of Flagstaff, Arizona. Environmental & Engineering Geoscience 1977;; xiv (2): 89–103. doi: https://doi.org/10.2113/gseegeosci.xiv.2.89 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract A seismo-tectonic study of Flagstaff, Arizona was conducted to determine the range of possible expected ground motion parameters which could originate from local and regional earthquake activity. This study is based on correlation of regional geology and historical earthquake data, obtained from multiple sources. The study concludes that the Flagstaff area could be affected by future major earthquake activity, consisting of a local event originating on the Oak Creek Canyon fault system. Distant events, originating in other seismically active areas of northwest Arizona and extreme southwest Arizona are not likely to produce significant ground motion at Flagstaff. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.