Geology Commons^™

Geometry, Timing, And Kinematics Of Neogene Extensional And Transtensional Structures Of Southern Death Valley: Implications For Regional Reconstructions And A Corrective Method For Rigid Body Rotations, Zachariah Fleming

Open Access Theses & Dissertations

Chapter 1:Advancements in computing capabilities over the last decade have allowed for the routine creation of Structure from Motion-Multiview Stereo (SfM-MVS) terrain models that can serve as base for high resolution geologic mapping. Outcrops models developed from these systems are high-resolution, photo-realistic 3D base providing unprecedented capability for geometric analysis. Yet, before this technology becomes a mainstay of field geology, the potential errors associated with it must be well understood. Here, we compare orientation measurements from multi-point analyses on the SfM-MVS point clouds to those taken in the field with the objective of resolving the geometry of complex folds within …

Characterization And Geochemistry Of Carbonate Caprock Associated With The Gypsum Valley Salt Wall, Paradox Basin, Colorado: Implications For Understanding Lateral Caprock Emplacement, Piper Lee Poe

Open Access Theses & Dissertations

On the northeastern side of Gypsum Valley salt wall in the Paradox Basin of Colorado, discontinuous exposures of layered gypsum and carbonate rocks were previously mapped as the contact between diapiric Paradox Formation and marine limestone of the Pennsylvanian Honaker Trail Formation. Utilizing new and existing mapping, petrographic and isotopic geochemical analyses, this study reinterprets this zone to represent lateral gypsum and carbonate caprock that formed in the Triassic during passive rise of the Gypsum Valley salt wall. Gypsum Valley lateral carbonate caprock can be distinguished from Pennsylvanian and Permian depositional carbonate strata exposed elsewhere on the salt wall by …

Attributes Of The Fisher Valley Megaflap And Comparison To The Gypsum Valley Megaflap, Paradox Basin, Utah And Colorado: Implications For Controls On Megaflap Formation, Kate Grisi

Open Access Theses & Dissertations

Megaflaps are panels of steeply dipping to overturned strata that extend kilometers up the side of a salt diapir or equivalent weld. They often form important components of salt-diapir related hydrocarbon systems, though little is known about their geologic characteristics or how they form. In this study, I collected structural, stratigraphic, and sedimentologic data of the Fisher Valley megaflap and compared these attributes to the previous studied Gypsum Valley megaflap to test the differential sediment loading model proposed for initiation of megaflap formation. This model predicts that the sediment source proximal megaflap of Fisher Valley should have started rotation earlier, …

Facies Changes Associated With Formation Of An Extensive Salt Shoulder By The Coastal And Eolian Carmel And Entrada Formations, Gypsum Valley, Colorado, Ryan Burtron Ronson

Open Access Theses & Dissertations

A salt shoulder forms a zone at the margin of a salt diapir where that margin steps relatively abruptly inward. These shoulders form when the salt rise rate near the diapir margin substantially decreases or stops relative to the salt rise rate at the inboard central part of the diaper. Based on current models of interactions between these salt shoulders and overlying sediment, it was anticipated that the thickness changes of the Entrada and Carmel formations would be only gradual and that any notable thinning would take place proximal to the neck portion of the diapir that would still have …

Gravitational Analysis And Fault Identification Within An Active Rift Basin: The Mesilla Valley Bolson In Western Texas - Southern New Mexico, Jose Pablo Cervantes

Open Access Theses & Dissertations

The metropolitan region of El Paso Texas and Ciudad Juárez, Chihuahua, located within the northern Chihuahua Desert, contains approximately two million inhabitants. The two main aquifers that supply groundwater to this region are the Mesilla and Hueco Bolsons. Both bolsons have been tapped for decades without sustainable recharge. This study's purpose is to use geophysical methods coupled with published geochemical analyses to determine the structural and stratigraphic controls on the quality and quantity of groundwater in the southern Mesilla Bolson.

The Mesilla Bolson is one of many fault-controlled basins within the Rio Grande Rift - southern Basin and Range. Faults …

Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa

Open Access Theses & Dissertations

For over a century, coal has been used worldwide to meet ever-growing energy demands. Coal combustion accounts for over 30% of electricity generation in the United States. In the U.S., coal combustion produces annually over 100 million tons of coal combustion products (CCPs) of which only 30% are used in beneficial and economic ways. One of the primary CCPs from coal-burning power plants is fly ash, typically fine-sized and enriched in many trace elements (e.g., arsenic, chromium, lead, and vanadium). When disposed in the environment, fly ash may release significant concentrations of trace elements into surrounding ecosystems and induce toxicity …

A Machine Learning Approach To Rendering 3d Stratigraphic Models Of The Hueco Bolson, Western Texas And Northern Mexico, Joel Gerardo Castro

Open Access Theses & Dissertations

Data visualization is an effective way to analyze large amounts of spatial information to identify correlations, trends, outliers, and patterns. In this Thesis I test the application of supervised machine learning algorithms to render a series of 3D visualizations designed to highlight general traits of the Hueco Bolson, a geologic basin located east of the Franklin Mountains in far west Texas and northern Mexico. A geologic basin is one of the most common inland places where sediments are collected. The geology of basins is of much interest to geophysicists, hydrologists, paleontologists, and oil prospectors. Here the task of 3D geologic …

Comparison Of Mesoscopic Fracture Analysis Techniques: A Case Study Near Onion Creek Diapir, Paradox Basin, Utah, Muhammed Tarik Iraz

Open Access Theses & Dissertations

Faults and fractures are abundant along the diapir contact in the Onion Creek Diapir in eastern Utah and relate to the mechanisms of diapir formation. Western Onion Creek exhumes two spectacular exposures of the diapir contact and adjacent wall rocks providing two nearly orthogonal transects oriented ~E-W and S-N. In this study, I used field measurements from natural outcrops and a 3D model developed using Structure-from-Motion/Multiview Stereo photogrammetry to evaluate fracture reservoir development along diapir margins. The 3D-Model was developed using Agisoft Photoscan from ~3200 ground-based images and was georeferenced using 76 ground control points located with a GPS unit …

Depositional Controls And Sequence Stratigraphy Of Lacustrine To Marine Transgressive Deposits In A Rift Basin, Lower Cretaceous Bluff Mesa, Indio Mountains, West Texas, Andrew Anderson

Open Access Theses & Dissertations

Successful hydrocarbon exploration in former rift basins of the South Atlantic pre-salt has generated interest in understanding depositional, diagenetic, and stratigraphic controls on pre-salt deposits. However, most studies to date have focused on attributes and controls on presalt lacustrine carbonate reservoir systems and little work has been done on the overlying marine sealing facies. Currently our standard sequence stratigraphic model of marine transgression of rift systems involves a single pulse of marine flooding over fluvially-incised valleys resulting in backstepping of fluvial and estuarine siliciclastic facies within the erosionally confined zone of an incised valley. However, the pre-salt systems of the …

Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer

Open Access Theses & Dissertations

Caprocks are found on top of or in a lateral position relative to salt diapirs. The caprocks predominantly comprise sulfate minerals such as anhydrite or gypsum, which presumably accreted during the dissolution of salt from evaporite sediments. In some cases, the sulfate minerals are replaced by carbonate minerals, referred to as "carbonate caprock". Carbonate caprocks associated with salt diapirs are important because they can act as reservoirs or conduits for hydrocarbons, and because they can be easily misidentified as carbonate lithologies belonging to the stratigraphy of the sedimentary sequences adjacent to the diapir, which can jeopardize the accurate interpretation of …

Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos

Open Access Theses & Dissertations

Hydrocarbon exploration in pre-salt sediments of rift basins on the South Atlantic Margin have proven to be successful major oil plays. Located on the western margin of the rift, the Brazilian pre-salt reservoirs of the Santos, Campos, and Espirito Santo Basins are hosted by lacustrine/marine-influenced carbonates that comprise laterally extensive, laminated microbialite facies. The Indio Mountains, located in West Texas, provide well-exposed outcrops of Lower Cretaceous marine and non-marine rift basin strata that can be considered a reservoir-analog to the South Atlantic Margin pre-salt facies. Of particular interest for hydrocarbon exploration are unique carbonate features that have been discovered in …

Constraining Times Of Extension In The Southern Rio Grande Rift And Basin And Range Using Apatite And Zircon (U-Th)/He Thermochronology, Julian Biddle

Open Access Theses & Dissertations

The Rio Grande rift and the Basin and Range are adjacent extensional domains that have evolved contemporaneously in western North America. Although the rift is often considered to be the easternmost boundary of Basin and Range extension, there is geologic and geophysical evidence that suggests the two are discrete provinces. Existing low-temperature thermochronologic data indicate that a period of synchronous extension occurred across the entire length of the rift from ~25-10 Ma. However, these studies were more focused on the northern and central sections of the rift, and thermochronologic data remains sparse in southern New Mexico. We collected rock samples …

A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason

Open Access Theses & Dissertations

Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypoThesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, …

Airborne Lead In El Paso, Texas, Usa, Lisa Marie Paz

Open Access Theses & Dissertations

Despite significant strides to minimize lead in our air, water, soil, food, homes, workplaces, and consumer products, sporadic and systemic lead poisoning persists in industrial societies, e.g., the contemporary Flint (Michigan, USA) municipal water tragedy. Because lead exposure is cumulative, the sum of exposure from all sources, it is important to document and update potential community or neighborhood exposure levels from such environmental compartments as air, water, and housing. Here we present ambient airborne lead levels in El Paso, Texas, USA, parsed by particulate matter (PM) size fraction, geography, and season. Dichotomous samplers at 8 stations collected particulate matter continuously …

Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea

Open Access Theses & Dissertations

Dry deposition significantly affects evolution of the critical zone by nutrient supply and contributing to soil genesis. Dust influx and cycling in soils are difficult to quantify because dust sources can be chemically similar to local soils. White Sands, New Mexico, emits gypsum dust with a unique chemical and isotopic signature, providing an opportunity to investigate dust deposition and its movement in soils. This study evaluated the mobility of White Sands dust particles in the critical zone at White Mountain, New Mexico, a highland 100 km downwind. Four soil profiles were collected over limestone, igneous, mixed limestone and dolostone, and …

Near-Surface And High Resolution Seismic Imaging Of The Bennett Thrust Fault In The Indio Mountains Of West Texas, Alan Thomas Vennemann

Open Access Theses & Dissertations

My research investigates the structure of the Indio Mountains in southwest Texas, 34 kilometers southwest of Van Horn, at the UTEP (University of Texas at El Paso) Field Station using newly acquired active-source seismic data. The area is underlain by deformed Cretaceous sedimentary rocks that represent a transgressive sequence nearly 2 km in total stratigraphic thickness. The rocks were deposited in mid Cretaceous extensional basins and later contracted into fold-thrust structures during Laramide orogenesis. The stratigraphic sequence is an analog for similar areas that are ideal for pre-salt petroleum reservoirs, such as reservoirs off the coasts of Brazil and Angola …

Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder

Open Access Theses & Dissertations

On the western margin of the Pennsylvanian/Permian Orogrande Basin, two composite measured sections in the Lower Permian upper interval of the Middle Member of the Hueco Limestone were analyzed in regards to depositional environment, facies and sequence stratigraphy. This can elucidate where potential unconventional reservoirs can be found in the Wolfcamp Shale of the Permian Basin. Based on these analyses, 12 lithofacies were identified, including 9 carbonate lithofacies: 1) fenestral dolomudstone, 2) peloidal dolomudstone, 3) ostracode foraminifera packstone, 4) foraminifera peloidal grainstone, 5) skeletal intraclast grainstone, 6) phylloid algal peloidal grainstone, 7) echinoderm phylloid algal packstone, 8) echinoderm bivalve brachiopod …

Structural And Stratigraphic Development Of A Salt Diapir Shoulder, Gypsum Valley, Colorado, Joshua Coleman Mcfarland

Open Access Theses & Dissertations

A salt shoulder is a low-angle segment of the salt-sediment interface where the margin of a passive diapir steps abruptly inboard. The Late Triassic Chinle Formation overlies caprock on the northeastern margin of Gypsum Valley (GV) at the salt-sediment interface in the natural amphitheater of Bridge Canyon. Modern erosion of the Dolores River has created 3D outcrop of the salt shoulder, expressed by a 500 meter wide, sub-horizontal platform that dips abruptly into the subsurface to the northeast toward the Dry Creek minibasin. Within Bridge Canyon, seven facies associations have been recognized and interpreted within the Chinle Formation: 1) non-caprock …

Geology, Geochemistry, And 3d Geological Modelling Of The Independencia - Los Bancos Ag-Au Epithermal Vein Systems In The Palmarejo District, Chihuahua, Mexico, Arturo Ramirez

Open Access Theses & Dissertations

The Sierra Madre Occidental (SMO) is a Cretaceous-Tertiary silicic ignimbrite province in northwestern Mexico. It is the result of tectonic and magmatic events produced by the subduction of the Farallon plate under North America (80-40 Ma) and the opening of the Gulf of California (14-12 Ma), thus forming the SMO metallogenic provinces. The Late Eocene to Oligocene was a major period of metallic mineralization hosting various deposit types, principally Ag-Au (±Pb-Zn-Cu) epithermal veins, which have been economically significant.

The study area lies in the Palmarejo district, operated by Coeur Mining Inc., which was the worldâ??s fifth largest silver producer in …

Geochemical Signatures As A Chemostratigraphic Tool To Correlate Stacked Carbonates Of The Glorieta, Victorio Peak, Cutoff, And Upper San Andres Formations West Dog Canyon, Guadalupe Mountains, New Mexico, Eric Bergersen

Open Access Theses & Dissertations

For oil exploration, stratigraphic correlation of formations over distance and across structural complications is essential. I tested if an established method – carbon and oxygen isotope composition of carbonates (δ 18Ocarbonate, δ13Ccarbonate) and a new chemostratigraphic tool – sulfur isotope composition of Carbonate Associated Sulfate (δ34SCAS) can aid in the correlation of rock packages belonging to multiple stacked carbonate horizons from a carbonate platform.

In my study area, located in the Brokeoff Mountains, north of the Guadalupe Mountains National Park, the δ18Ocarbonate, δ 13Ccarbonate and δ34SCAS scatter strongly within single beds of the Leonardian-aged Victorio Peak Formation. In stratigraphic order, …

Tectonostratigraphic Evolution Of A Suprasalt Minibasin, Oligocene - Miocene Western Slope Of The Gulf Of Mexico, Felix Alan Ramirez

Open Access Theses & Dissertations

The petroleum industry has focused Gulf of Mexico exploration efforts on salt-related geologic provinces in search of major hydrocarbon accumulations. This work has led to recognition of the influence that salt tectonics has had on play elements of the petroleum system in the producing salt basins. In particular, the complex depositional patterns of the reservoir rocks controlled by shifting depocenters resulting from the accommodation space generated by salt withdrawal from minibasins.

The focus of this research is to understand the structural and stratigraphic components that controlled the evolution of an Oligocene - Miocene suprasalt minibasin located in the upper continental …

Geophysical Constraints On The Hueco And Mesilla Bolsons: Structure And Geometry, Victor Manuel Avila

Open Access Theses & Dissertations

The Hueco and Mesilla Bolsons are part of the intramountain basins of the Rio Grande Rift system. These bolsons are the primary source of groundwater for the El Paso-Ciudad Juarez metropolitan area and contain faults that show evidence of repeated earthquakes during the Quaternary. The region is also associated with has low-level (M<4) seismicity. The collection and analysis of precision gravity data, coupled with information from water wells, multichannel analysis of surface waves (MASW) studies and previously published seismic reflection lines, have been used to examine the structure and faulting within these bolson. This study reveals that the Hueco and Mesilla Bolsons are very different structurally. The southern Mesilla Bolson contains about 500 m of sediment. Faults are difficult to trace and have less than 50-100 m of displacement across them. The southernmost bolson contains numerous Tertiary intrusions and the thickness of Cretaceous bedrock appears to decrease from south to north, possibly delineating the edge of Laramide age deformation within the bolson. The northern Hueco Bolson contains 1800 to 2500 m of basin fill. Displacement along the East Franklin Mountains fault (EFMF), a fault with evidence for repeated earthquakes within the past 64,000 years, is about 1500 m, and displacement on intrabasin faults is 200-300 m. Several intrabasin faults appear to control the saline to freshwater contact within the bolson. The EFMF may extend over 30 km south of the end of its mapped trace at the end of the Franklin Mountains and a number of intrabasin faults also extend south into the urbanized regions of the study area. The EFMF and other basin structures appear to be offset or disrupted at the speculated edge of Laramide deformation that lies beneath the bolson. Horizontal Gradient Methods (HGM) were applied to the gravity data and were successful for tracing faults and older Laramide features within the Hueco Bolson beneath the urbanized regions of the cities. HGM were not as successful at tracing faults within the Mesilla Bolson, however they were helpful for tracing the subsurface extent of igneous intrusions including the Mt. Cristo Rey, River, Three Sisters, and the Westerner outcrops. Some of these features appear linked at depth by a series of dikes and faults. MASW data were used to determine the average shear wave velocity in the upper 30m (Vs 30) at ~70 sites within the Hueco Bolson. These observations were combined with similar data collected previously in Juarez to produce regional velocity and site classification maps. The results show low velocities are found close to the river within fluvial deposits with higher velocities close to the Franklin Mountains where bedrock is close to the surface and higher velocities in upland regions of northeast El Paso were soils appear to be more highly cemented. These data will be used in conjunction with information on bolson geometries to model the expected effects of strong ground motion from earthquakes in the El Paso-Ciudad Juarez region.

Sedimentologic And Stratigraphic Analysis Of Synrift Siliciclastic Fluvial And Lacustrine Strata In The Lower Cretaceous Upper Yucca Formation, Indio Mountains, West Texas, Matthew Robert Fox

Open Access Theses & Dissertations

Outcrops of the upper Yucca Formation in the Indio Mountains near Van Horn, Texas provide temporal, tectonic, and climatic similarities to Lower Cretaceous, synrift, greenhouse pre-salt lacustrine strata along in the subsurface of the South Atlantic margin. These "pre-salt" strata hold prolific petroleum reservoirs but despite extensive seismic studies performed for regional scale hydrocarbon exploration in these lacustrine reservoirs, sedimentologic and stratigraphic analyses have rarely been published. The Upper Yucca Formation in the Indio Mountains contain lacustrine reservoir analogs that intertongue with fluvial and deltaic sandstones. Near Squaw Canyon, fluvial-deltaic sandstones are reduced in abundance to lacustrine carbonates by nearly …

Salt Tectonic Controls On Facies And Sequence Stratigraphy Of The Triassic Chinle Formation, Gypsum Valley Salt Wall, Colorado, Elizabeth Heness

Open Access Theses & Dissertations

This study focuses on mapping the facies geometry and depositional sequences of the Chinle Formation adjacent to the Gypsum Valley Salt Wall (GVSW). Interactions between salt tectonics and fluvial systems can affect sediment distribution. The upper Triassic Chinle Formation was deposited across the western U.S. in an intra-cratonic, fluvial environment. Throughout the Paradox Basin in Utah and Colorado, deformation associated with rising salt anticlines and subsiding minibasins coincided with Chinle deposition. In most areas, only small and isolated remnant Chinle outcrops actually expose the contact between Chinle sediments and the salt diapir. In Gypsum Valley three study areas were mapped …

Quantifying A Mining Investability Quotient To Mitigate Junior Mining Investment Risk, Jonathan Mickey Merguerian

Open Access Theses & Dissertations

Uncertainty and risk are inherent features of investing in mineral exploration ventures. Investors rely on qualitative and quantitative analysis to evaluate risk of capital. The distinction between risk and uncertainty pertaining to mineral exploration is that risk is an opportunity for loss and uncertainty can be described as the range of probabilities that some condition may occur (Rose, 1987). Stakeholders rely on a combination of investment conferences, risk analysis equations, press releases, financial reports, and investment research to determine if an investment potential. J. M. Cozzolini developed a formula for Risk Adjusted Value (RAV) of an exploration venture. The study …

An Integrated Geophysical Survey Of Kilbourne Hole, Southern New Mexico: Implications For Near Surface Exploration Of Mars And The Moon, Nisa Maksim

Open Access Theses & Dissertations

Features such as the Home Plate plateau on Mars, a suspected remnant of an ancient phreatomagmatic eruption, can reveal important information about paleohydrologic conditions. The eruption intensity of a phreatomagmatic volcano is controlled mainly by the quantity of water and magma, the internal geometry of the volcano, and the depth of the interaction zone between magma and water. In order to understand the paleohydrologic conditions at the time of eruption, we must understand all the factors that influenced the phreatomagmatic event. I conducted an integrated geophysical survey, which are magnetic and gravity surveys, and a ground-penetrating radar (GPR) surveys at …

National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray

Open Access Theses & Dissertations

The U.S. Geological Survey recently updated a geochemical database consisting of data for approximately 160,000 produced waters samples, primarily from petroleum and geothermal reservoirs. Using major and trace elements from conventional and unconventional well types from the database, this Thesis provides a comprehensive, national evaluation for mineral commodity potential in produced waters. Produced waters contain virtually every naturally occurring element and can range in salinity to several times that of seawater. Despite the typical outlook to view produced waters as a waste, they have potential for natural resource development.

This Thesis provides, for each mineral commodity found in the produced …

Investigation Of Lunar Subsurface Cavities Using Thermal Inertia And Temperature Maximum To Minimum Ratios, Rachel Ann Slank

Open Access Theses & Dissertations

Previous studies have revealed a small number of subsurface cavities, including lava tubes, as well as skylights, lava flow pits, and impact melt pits on the Moon. The interiors of subsurface cavities would have been protected from micrometeorite bombardment, solar radiation, space weathering, and extreme diurnal temperature swings over long periods of geologic time. As a result, subsurface cavities can provide access to pristine crustal samples and stratigraphy. These cavities may also harbor important volatiles, such as water ice, that would enable future exploration missions by relieving many operational constraints, including the supply of propellants and life support. In addition, …

Reconstructing Late Pleistocene And Holocene Paleoenvironments Using Playa-Lunette System Sediments Within The Harney Basin Of Southeastern Oregon, Usa, Joe Collins

Open Access Theses & Dissertations

Paleoenvironmental investigations of the Late Pleistocene and Early Holocene in the Harney Basin of eastern Oregon have been limited to date. This Dissertation investigates and links the stratigraphy of Rimrock Draw Rockshelter (35HA3855) (RDR) and two surrounding playas, Rimrock Lake and Hay Lake, located on the western margin of the Harney Basin, in order to identify paleoenvironmental shifts during the last ~20 kyr. An emphasis also is given to demonstrating the potential for playas in the Harney Basin to record changes in paleoclimate, as well as the application of multivariate statistics to interpret paleoenvironments from sedimentary grain size data. Stratigraphy …

Regional Geochemical Mapping Of The Superior Upland Province; Ichnology Of The Cretaceous Mesilla Valley Formation, Cerro De Cristo Rey; A New Ichnospecies Of Cardioichnus From The Cretaceous (Albian) Of New Mexico; A Pedagogy For The Cerro De Cristo Rey Tracksite; Walking In The Footprints Of Dino, Eric J. Kappus

Open Access Theses & Dissertations

This is a multi-disciplinary study that covers a variety of geoscience topics on both international borders of the continental United States. This Dissertation is the product of several separate investigations. First is a report on the landscape geochemistry of the Superior Upland Province of Minnesota, Wisconsin, and Michigan, with regional maps of 37 chemical elements interpreted in terms of bedrock, glacial reworking, and anthropogenic influence. The next 2 sections are reports on the invertebrate ichnology of the Cretaceous Mesilla Valley Formation at Cerro de Cristo Rey, including the proposal of a new ichnospecies of echinoid resting trace, Cardioichnus biloba nov. …