Chan's studies have examined aspects of sedimentology and diagenesis in this important reservoir unit. Kayenta Formation deposition was ended by the encroaching dune field that would become the Navajo Sandstone. Prices and download plans . ; Kettler, R.M. Concretions hold the key to understanding diagenesis (i.e., what happens between the time sediments are deposited and when the rock is uplifted and exposed). Sign in Sign up for FREE Prices and download plans These iron oxide concretions typically display a rinded structure: dense sandstone . Navajo/Spruce/Lodge Trails UT (1) Nevis (1) New York City (1) No Mans Mesa UT (1) North Lovell Peak NV (1) Northgate Peaks UT (1) Observation Point UT (1) Both Navajo Sandstone concretions and Mars spherules on Meridiani Planum are enriched in Ni relative to the host rock (Morris et al. 2). The rinded iron oxide concretions found in the Navajo Sandstone (Utah, USA) have been among the most extensively studied of these occurrences. Field relationships, precipitation patterns, and g. The iron-oxide-rich concretions in the Jurassic Navajo Sandstone in southern Utah are unusual in two fundamental ways. They are either deposited along fractures/faults or form layers of hematite-cemented sandstone, referred to as ferricretes [19]. Manitou itself was seen to rest in rocks and boulders, sometimes referred to as 'spirit' or 'image' stones. June 2012 - Moqui Marbles. CHARACTERIZATION OF NAVAJO SANDSTONE HYDROUS FERRIC OXIDE CONCRETIONS by Sally Latham Potter A thesis submitted to the faculty of The University of Utah in partial . In this study, the Fe isotopic compositions of 3 tabular concretions were measured (E#15-3, CR#40 and . Large-scale cross strata composed of wind-ripple and dry avalanche (grain- ow) deposits make up more than 95% of the formation. Name / Title. First, they are cemented by iron oxide (Fe 2 O 3 , or Fe(OH) 3 ); most other concretions are cemented by silica (SiO 2 ), calcite (CaCO 3 dolomite (CaMg(CO 3 2 ), or siderite (FeCO 3 Second, unlike The iron forming these concretions came from the break down of iron-bearing silicate minerals by weathering to form iron oxide coatings on other grains. Most are found in the numerous national parks in the area, so they can no longer be collected. In the lower Navajo Sandstone where cross bedding is more prevalent and undisturbed, concretions are either spheroidal (within thick grainflow beds) or discoidal where concretions grow in alternating wind ripple and grainflow laminae. geochemical modeling performed in this research explored the question of fluid chemistry involved in concretion formation in the navajo sandstone and findings suggest that the calcite concretions formed prior to the precipitation of secondary iron (oxyhydr)oxides and may have provided a localized buffering environment for the precipitation of Iron oxide concretions are formed from post depositional, paleogroundwater chemical interaction with iron minerals in porous sedimentary rocks. Much of the mechanical ingenuity we know of in modern times began to develop only a couple hundred years ago, during the Industrial Revolution. The Jurassic Navajo Sandstone of southern Utah in southwestern USA commonly hosts concretions cemented by iron oxides (Potter 2011, Loope 2012). Jurassic Navajo Sandstone Chan's group has been conducting research on the Jurassic Navajo Sandstone for over two decades. The iron forming these concretions came from the breakdown of iron-bearing silicate minerals by weathering to form iron oxide coatings on other grains. It is therefore desirable to examine apparently unaltered Navajo Sandstone to identify the starting 56 Fe value of the system. Well-exposed Jurassic Navajo Sandstone iron oxide concretions preserve important diagenetic records of groundwater flow and water-rock interactions. . Many scientists attempt to explain these ooparts away as natural phenomena. At least four different models have been. This eolian deposit was the largest desert or sand sea erg in the geologic record. Loope, D.B. Carl Baugh, who was in possession of the artifact, has said the wooden handle has turned to coal (evidence of its great age) and that the metal . . . Object Number / Field Number / Film ID. Concretions cemented by iron oxide are abundant and diverse in the Jurassic Navajo Sandstone of southern Utah. Field relationships, precipitation patterns, and geometries of the Navajo concretions provide the basis for input parameters in numerical computer simulations and laboratory chemical bench tests. These iron oxide concretions typically display a rinded structure: dense sandstone . What is iron concretion? 1 Introduction The eolian Jurassic Navajo Sandstone is widely exposed throughout southern Utah and northern Arizona and is the largest erg that exists on modern or ancient Earth ( Blakey, 1994; Blakey et al., 1988 ). Abstract Concretions cemented by iron oxide are abundant and diverse in the Jurassic Navajo Sandstone of southern Utah. . Wellexposed Jurassic Navajo Sandstone iron oxide concretions preserve important diagenetic records of groundwater flow and water-rock interactions. Sign in Sign up for FREE Prices and download plans The canyon walls are reddish and tan-colored Navajo Sandstone eroded by the North Fork of the Virgin River. XRD analysis of the concretion shows diagnostic peaks for quartz, hematite, and goethite. Some of these structures are considered terrestrial analogs for concretions imaged on Mars. The Jurassic Navajo Sandstone of southern Utah in southwestern USA commonly hosts concretions cemented by iron oxides (Potter 2011, Loope 2012). Thousands of moqui marbles, concretions of iron oxide minerals, accumulate in small troughs eroded into the Navajo Sandstone, Snow Canyon State Park, Utah Southern Utah is a mecca for tourists from around the world, and most of that blame can be placed on the shoulders of a single layer of rock: the Navajo Sandstone. The concretions appear to have formed by filling pore spaces between the aeolian sand grain matrix that hosts them, without disturbing the sand matrix. Rind end-member (Concretions are masses of hardened mineral matter). Some of these structures are considered terrestrial analogs for concretions imaged on 36 Highly Influenced PDF View 4 excerpts, cites background Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars They occur in many places in southern Utah either embedded in or gathered loosely into "puddles" on the ground near outcrops of Jurassic age Navajo Sandstone. Two end-members of micro-concretions are rind and solid. . Serial sections and 3D reconstruction of a Navajo Sandstone iron oxide concretion (Navajo sample A) Figure 1. Abstract The Jurassic Navajo Sandstone of Grand Staircase Escalante National Monument (GSENM), Utah, exhibits a broad range of iron oxide/oxyhydroxide concretionary geometries that record a complex. A reducing fluid infiltrated the sandstone and mobilized the iron into solution as Fe 2+ . 3.1.1. WikiMatrix. First cut. unit called the Navajo Sandstone features prominently in this landscape, and contains some of the largest and most abundant iron concretions found anywhere in the world. Bleaching and Concretions The Navajo Sandstone is white within the Escalante anticline, but is stained red to the southeast, where gently dipping homoclinal beds are exposed along the Escalante River (Fig. The iron forming these concretions came from weathering on other grains to form iron oxide coatings, which broke down iron-bearing silicate minerals and formed iron oxides. Sandstone balls are cemented with a strong layer of iron oxide minerals. The iron-oxide-rich concretions in the Jurassic Navajo Sandstone in southern Utah are unusual in two fundamental ways. Petrography of concretions shows abundant quartz grains embedded within the iron oxide cementation. The abundant concretions found in the Navajo Sandstone consist of sandstone cemented together by hematite (Fe 2 O 3 ), and goethite (FeOOH). During later diagenesis of the Navajo Sandstone while . Spheroidal concretions composed of an iron oxide-rich cemented outer rind and a weakly-cemented core of bleached (iron depleted) sandstone are abundant in the Jurassic Navajo Sandstone of the Colorado Plateau. Some examples of anhydrous secondary minerals include many carbonates, some sulfates (e.g., anhydrite), and metallic oxides such as the iron oxide mineral hematite. The Navajo concretions can be spheroidal, pipelike, or tabular with multicompartmented boxworks. The larger piece was sectioned. Navajo sandstone at The Wave, Arizona, by David Coppedge Navajo sandstone is often accompanied by "moqui marbles" on its surface: rounded iron pebbles that have eroded out of the sandstone . Where the Navajo Sandstone loses its iconic peach, orange and red stripes, hundreds of round, iron-coated stones often litter the ground. From oldest to youngest, these are the Wingate Sandstone, Moenave Formation, Kayenta Formation, and Navajo Sandstone. On the hike out we couldn't help but notice streaks of iron oxide concretions embedded in the sandstone (Little Creek Mountain HP just turned out to be a numbered point on the mesa rim . Characterization of Navajo Sandstone Concretions: Mars Comparison and Criteria for Distinguishing Diagenetic Origins; Pedogenic Hematitic Concretions from the Triassic New Haven Arkose, Connecticut: Implications for Understanding Martian Diagenetic Processes; Fe-Mn Concretions and Nodules to Sequester Heavy Metals in Soils These round rocks form in the Navajo Sandstone formations spread across northern Arizona, northwest Colorado, and Utah. Top right, bottom left: Similar objects known as Moqui marbles from the Navajo Sandstone of southeast Utah . Although overall Navajo Sandstone spheroidal concre- tions range from mm-sized "blueberries" to >10 cm-sized "grapefruits," within any one reaction front population there is generally a consistent size. The iron forming these concretions came from the breakdown of iron-bearing silicate minerals by weathering to form iron oxide coatings on other grains. Left: (Brian A Jackson/Shutterstock); Right: (Lasse Jensen/CC BY 2.5) "Oopart"or "out-of-place artifact"is the term given to numerous prehistoric objects found in various places across the world today that show a level of technological sophistication incongruous with our present paradigm. Known as concretions, these pebbles, secular geologists tell us, have a completely different history than the rock that encases them. The typically iron-rich minerals oxidise rapidly in water and air, staining the rock a brown to red colour due to iron oxide (rust . All models for the genesis of the Navajo concretions contend that the iron oxide that coats sand grains in the Navajo serves as the primary source for the iron in the concretions. The abundant concretions found in the Navajo Sandstone consist of sandstone cemented together by hematite (Fe 2 O 3), and goethite (FeOOH). Abstract The iron oxide concretions of Shankargarh (Allahabad), India belongs to Dhandraul Sandstone of Vindhyan Supergroup. Context. The eolian Jurassic Navajo Sandstone spheroidal hydrous ferric oxide (HFO) concretions are divided into two sizeclasses:macro-concretions ofN5 mmdiameterandmicro-concretionsofb5 mmdiameter.Threeinternal structural end-members of macro-concretions are described as rind, layered, and solid. The A-CN-K and A-CNK-FM ternary diagrams drawn for concretion and host . The iron-oxide-rich concretions in the Jurassic Navajo Sandstone in southern Utah are unusual in two fundamental ways. Article history: The eolian Jurassic Navajo Sandstone spheroidal hydrous ferric oxide (HFO) concretions are divided into two Received 1 June 2010 size classes: macro-concretions of N5 mm diameter and micro-concretions of b5 mm diameter. The red rock country on the Colorado Plateau where the Navajo Sandstone and other . The Navajo Sandstone was deposited near the western edge of Pangea in a vast, Early Jurassic sand sea (Kocurek and Dott, 1983). The mineral of the month for this update is an unusual type of iron concretion called Moqui Marbles. Figure 1. The Navajo Sandstone was named for the "Navajo country" of Arizona, Utah, and New Mexico. Moqui marbles, the colored stones spread over the Utah and Arizona, are often called as a stone, and they fall off pale, cream-colored Navajo Sandstone beds when wind and water wash away the softer rock are often known by the name Moqui. Authored by Tara Macisaac via The Epoch Times (emphasis ours), According to our conventional view of history, humans have only walked the Earth in our present form for some 200,000 years. . Prices and download plans . The iron forming these concretions came from the break down of iron-bearing silicate minerals by weathering to form iron oxide coatings on other grains. This may be the result of Ni mobilization and precipitation adsorbed to the more abundant iron species; however, this trace element phenomenon warrants further investigation with . 2006, Potter and Chan 2011). "The abundant concretions found in the Navajo Sandstone consist of sandstone cemented together by hematite (Fe2O3), and goethite (FeOOH). The abundant concretions found in the Navajo Sandstone consist of sandstone cemented together by hematite (Fe 2 O 3), and goethite (FeOOH). Moqui marbles are small, brownish-black balls composed of iron oxide and sandstone that formed underground when iron minerals precipitated from flowing groundwater. In general, small con- cretions are more closely spaced, and larger concretions are more widely spaced (Chan et al., 2004). 2B). Moqui Marbles, also called Moqui balls or "Moki marbles", are iron oxide concretions which can be found eroding in great abundance out of outcrops of the Navajo Sandstone within south-central and southeastern Utah. (Concretions are masses of hardened mineral matter). Combined single-grain (U-Th)/He and U/Pb dating of detrital zircons from the Navajo Sandstone, Utah 2003: Late Cretaceous-Cenozoic exhumation history of Tiantangzhai region of Dabieshan Orogen: Constraints from (U-Th)/He and fission track analysis 2003: Pliocene and Pleistocene exhumation and uplift of two key areas of the Northern Apennines 2003 The stony spheres are concretions sandstone balls. WikiMatrix. First, they are cemented by iron oxide (Fe2O3, or Fe (OH)3); most other concretions are cemented by silica (SiO2), calcite (CaCO3), dolomite (CaMg (CO3)2), or siderite (FeCO3). They were once a common feature of the landscape. The Navajo concretions can be spheroidal, pipelike, or tabular with multicompartmented boxworks. Description Although it can be argued that this may result in underestimating cm-scale concretions and thus the cumulative volume of cemented vs. host sandstone, it must be born in mind that concretions smaller than the cell size (i.e., 0.001 m3 ) represent less than 0.01% of the total volume of the observed concretions (Figure 8d). Abstract Concretions cemented by iron oxide are abundant and diverse in the Jurassic Navajo Sandstone of southern Utah. Beitler et al. iii. Hematite (Fe2O3) and goethite (FeOOH) cement sandstone together in great quantities in the sandstone deposits of the Navajo Sandstone. Some of these structures are considered terrestrial analogs for concretions imaged on Mars. Concretions can help us understand ground water better - water that we use for drinking and irrigation and need to keep clean. Carl Baugh, who was in possession of the artifact, has said the wooden handle has turned to coal (evidence of its great age) and that the metal its made of has a strange composition. (2003) related this color contrast to bleaching by buoyant, reducing u-ids that migrated through the Navajo Sandstone Some examples of anhydrous secondary minerals include many carbonates, some sulfates (e.g., anhydrite), and metallic oxides such as the iron oxide mineral hematite. In the Navajo Sandstone, Fe-oxide deposits also occur as massive, cm- to m-scale, tabular concretions ( Fig. The iron oxide concretions found in the Navajo Sandstone exhibit a wide variety of sizes and shapes. ~185-180 million years ago The Navajo Sandstone consists of thick layers of cross-bedded sandstone formed by windblown sand dunes in a vast ancient desert. The Navajo Sandstone is one . The range of colors of the Navajo Sandstone -red, brown, pink, salmon, gold, and even whiteresults from varying amounts and forms of iron oxide within the rock, and in the case of the white upper portion of the Navajo, the overall lack of iron. ; Weber, K.A., 2011: Morphologic clues to the origins of iron oxide-cemented spheroids, boxworks, and pipelike concretions, Navajo Sandstone . Where the oxidizing and reducing fluids mixed, the iron precipitated within the Navajo Sandstone. In the early Jurassic, the climate of the Colorado Plateau dried significantly, creating desert conditions over a broad region. These concretions range in shape from spheres to discs, buttons, spiked balls, cylindrical forms, and other odd shapes. First, they are cemented by iron oxide (Fe2O3, or Fe(OH)3); most other concretions are cemented by silica (SiO2), calcite (CaCO3), dolomite (CaMg(CO3)2), or siderite (FeCO3). The Navajo Sandstone is a geologic formation in the Glen Canyon Group that is spread across the U.S. states of southern Nevada, northern Arizona, northwest Colorado, and Utah; as part of the Colorado Plateau province of the United States. Iron precipitation: When this . For many of the Native people living here, manifestations of the supernatural could be expressed by one word: Manitou. The park was named for its whitish Navajo Sandstone cliffs with dome formationssimilar to the white domes often placed on capitol buildingsthat run from the Fremont River . 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