Clastic Pipes Research Articles

An erg landscape mystery: An exotic boulder in Jurassic aeolian‐fluvial deposits, Grand Staircase Escalante National Monument, Utah, USA

An unusually large exotic boulder occurs in strata close to the interfingering transition of the fluvial deposits of the Lower Jurassic Kayenta Formation and aeolian deposits of the Lamb Point Tongue of the Jurassic Navajo Sandstone in Grand Staircase Escalante National Monument, Utah. This boulder is composed of a weakly bedded, pink, thrombolitic burrowed mudstone and siltstone in a carbonate mudstone matrix. Comparison with similar carbonate units of the region—interpreted as lacustrine in origin and associated with interfingering deposits of Kayenta‐Navajo strata—indicates that the strata from which the boulder originated was likely a product of wind‐blown silt deposited in carbonate mud of a shallow lake. The exotic boulder is clearly embedded in and is eroding out of mostly massive to weakly bedded Jurassic, fine‐ to medium‐grained host sandstone. Nearby, the sandstone is disrupted by soft‐sediment deformation. The upper half of the enclosing sandstone shows low‐angle cross‐stratification that abuts against the edge of the boulder, indicating that Jurassic sedimentation lapped up against the sides of the boulder. Surprisingly, the exotic boulder does not co‐occur with any other clasts of similar lithology, nor is any obvious source lithology present within the immediate area. Lake beds of similar lithology in the same region are not physically traceable to the site where the exotic boulder occurs. The exotic boulder is evidence of the dynamic processes of the Jurassic landscape. The collective characteristics of the massive sandstone with typical polygonal weathering patterns and clusters of clastic pipes in the lower host rock suggest that the exotic boulder was emplaced in one of three ways: (A) fluid overpressurization, likely triggered by strong ground motion, produced the massive and deformed sandstone host and transported the boulder upward in the subsurface; (B) the block was an erosional remnant produced by Jurassic landscape degradation; or (C) the block was transported by a hyperconcentrated overland flow.

Sedimentology, diagenesis, and reservoir characterization of the Permian White Rim Sandstone, southern Utah: Implications for carbon capture and sequestration potential

Rising CO2 emissions have caused scientists and policy makers to explore potential solutions to reduce atmospheric CO2 levels, including carbon capture and sequestration. This project, funded through the Department of Energy CarbonSAFE initiative, aims to characterize the potential storage capacity and preferential fluid-flow pathways through the Permian White Rim Sandstone on and near the San Rafael Swell, Utah, to assess the formation’s viability as a possible CO2 sequestration reservoir. A diverse suite of sedimentological observations and diagenetic analyses was used to assess the White Rim Sandstone’s reservoir potential, including detailed outcrop observations, facies descriptions and ichnology, measured stratigraphic sections with associated correlations, permeability measurements, thin-section petrography, and visible and near-infrared spectroscopy. Stratigraphically, the White Rim Sandstone has two major units separated by a marine transgressive surface. The lower eolian unit is characterized by decimeter- to meter-scale trough cross-bedded grain-flow and wind-ripple facies. The upper reworked, shallow-marine unit has a consistent set of facies at all three field sites: (1) soft-sediment deformation facies (e.g., contorted bedding or clastic pipes), (2) symmetric ripple laminations, (3) bioturbated (dominantly horizontal), and (4) bioturbated (dominantly vertical). This set of four facies represents the transgression of the Permian Kaibab sea over the Permian White Rim coastal dune field. The outcrop samples and subsurface core samples (∼1561–2243 m deep and ∼33–50 km away from the outcrop localities) experienced different diagenetic fluid-flow histories that drastically impacted the reservoir properties. Outcrop samples have initial quartz overgrowth cements followed by rim-forming calcite cements, iron oxide cements, and occasional oil staining. In contrast, the core samples show significant compaction, followed by quartz overgrowth cementation and a later stage of patchy, large, pore-filling calcite cement that eliminated the porosity and permeability of the potential reservoir (<0.1 md). Outcrop permeability values tend to reflect textural differences in facies, particularly the presence and spacing of internal laminations and bounding surfaces. Facies with fewer internal laminations, such as the grain-flow facies, have higher permeability values than facies with closely spaced internal laminae, such as the wind-ripple facies. Disruption of original bedding (e.g., soft-sediment deformation or bioturbation) alters original depositional textures and creates preferential flow pathways with the potential to increase permeability. Overall, if the diagenesis and resulting low permeability values of the core samples are representative of the White Rim Sandstone at depth, then the White Rim Sandstone would not make a high-quality storage reservoir despite initial, promising outcrop results.

The Wind-Swept Nautilus, Enigmatic Clastic Pipes, and Toadstool Landforms: Geologic Features of the Paria Plateau

The Colorado Plateau occupies much of the southwestern United States including portions of Arizona, Colorado, Utah, and New Mexico. This region presents unobstructed views from mesa tops, beautifully colored soils, lone standing buttes, and canyons cut thousands of feet deep. The Colorado Plateau represents a well-preserved window into the Earth’s history. Today, the rocks of the Colorado Plateau lie roughly horizontally, as they were deposited hundreds of millions of years ago. The Plateau’s rise has motivated rivers, in their downhill progress, to carve innumerable canyons. These river canyons allow any nature-lover the opportunity to gaze at 100s of millions of years of geologic history. Within the larger Colorado Plateau, the Paria Plateau straddles the Utah and Arizona borders, and includes the Vermilion Cliff s National Monument, the Paria Canyon-Vermilion Cliffs Wilderness Area, and the southern extent of the Grand Staircase Escalante National Monument (GSENM; pre-2018 boundaries). The Paria Plateau is best known for spectacularly colored, wind-sculpted features such as Coyote Buttes and “The Wave,” where vivid colors accent cross-strata resembling a cresting ocean wave. The Plateau is also recognized for the geologically notable Vermilion Cliff s, Buckskin Gulch slot canyon, White Pocket area, and the Paria River Canyon. Although only two, dual-lane highways circumvent the plateau, several wash-boarded gravel and deeply mud-rutted roads allow access to its interior. From these dirt roads, a few sandy, four-wheel drive paths diminish as they extend and branch into the plateau’s interior. Overall, the Paria Plateau is a relatively quiet and little-visited wilderness.

Clastic pipes and mud volcanism across Mars: Terrestrial analog evidence of past martian groundwater and subsurface fluid mobilization

Clastic pipes are cylindrical injection features that vertically crosscut bedding with sharp contacts. Terrestrial pipes have cylindrical morphologies, massive or radially graded interiors, and raised outer rims. Increased grain size and subsequent cementation along the more porous edges makes the rims more resistant to weathering. Pipes have crosscutting relationships with other pipes due to multiple formation events or migrating eruption centers, and are associated with other soft-sediment deformation features. Terrestrial clastic pipes form via liquefaction and fluidization, which require a near-surface groundwater system to initiate (i.e., sand-sized sediments must be saturated for pipes to form).Clastic pipes (cm to 1000+ m diameters) occur on Mars across multiple time periods and terrains and are recognized in both rover and orbital imagery. A conical or cylindrical geometry and massive interior/core characterize these features. The pipes on Mars show various geomorphic expressions and are classified into five types by the presence or absence of a raised outer rim, or a central pit. These types are interpreted to represent the erosional evolution of pipes at different stages from their initial surface eruptive structures to their weathered remnants (eroded conical hills). Martian pipes formed via fluidization as evidenced by: 1) raised outer rims possibly indicating textural differences along the pipe edges from traction interactions of fluid-suspended sediment; 2) crosscutting relationships with other pipes suggesting reactivated fluidization pathways or migrating eruptive vents; and 3) close spatial association between pipes and other features thought to form by soft-sediment deformation (e.g., contorted bedding). Integration of terrestrial analog data with the Mars observations provides evidence for past Martian groundwater and subsurface fluid mobilization.

Clastic Pipes and Soft-Sediment Deformation of the Jurassic Carmel Formation, Southern Utah, U.S.A.: Implications For Pipe Formation Mechanisms and Host-Rock Controls

Abstract Vertically oriented columns of sandstone, termed clastic pipes, are common in Jurassic deposits of the Colorado Plateau. Exposures in the sabkha to fluvial strata of the Carmel Formation in southern Utah provide an excellent opportunity to understand pipe-formation mechanisms and controls on their expressions. These clastic pipes demonstrate significant variability and fall into two major categories: (1) primary textural pipes and (2) non-textural pipes. Primary textural pipes show significant textural differences relative to the host rock, including an internal outward grain coarsening indicative of traction structures. The pipes contain entrained, brecciated host material, and the surrounding host rock has associated soft-sediment deformation. Primary textural pipes formed through multiple liquefaction and fluidization events as evident from crosscutting pipes, multiple eruption horizons, traction structures, and other evidence of fluid-suspended-sediment transport. Non-textural pipes do not have significant textural differences from the surrounding host rock but have clear diagenetic differences (e.g., mineral coloration and cement differences) relative to the host rock. These non-textural pipes formed through the upward expulsion of fluids similar to primary textural pipes, but the fluid forces were likely insufficient to fully fluidize the sand. Overall, the porous, sandstone host rock plays a key role in explaining pipe characteristics, including their cylindrical geometry (versus tabular geometries in mudstones) and diagenetic expression. Pipe variability typically corresponds to lithologic and stratigraphic changes in the surrounding host rock. These pipe examples are key paleoenvironmental indicators, which give valuable information about subsurface fluids and the presence of a near-surface groundwater system.

Enigmatic clastic pipe swarms and implications for fluidization dynamics in aeolian deposits

AbstractSoft‐sediment deformation of contorted and massive sandstone is common throughout much of the siliciclastic record, but clastic pipes represent a distinctive class of pressurized synsedimentary features. Remarkable centimetre to metre‐scale clastic pipe exposures in the Jurassic Navajo Sandstone of Utah (USA) establish a range of pipe sizes, expressions and relationships to the host rock in an erg margin setting, traditionally thought to be just a dry desert system. In particular, the field and laboratory characterizations of cylindrical pipes show internal concentric, annular rings that imply water fluidization, with alignment of long grain axes due to shear flow along pipe margins. Central interior parts of decimetre‐scale pipes appear massive in plan view, but display weakly developed pseudobedding from post‐pressure release, gravitational settling in the cross‐sectional view. Deformation features of conjugate fractures, ring faults, hypotrochoid patterns (geometric arcs and circles) and breccia in the host material reflect both brittle and ductile behaviour in response to the fluidization and injection of the clastic pipes. The stratigraphic context of individual pipes and the stratabound intervals of pipe features imply dynamic deformation nearly coincident with deposition in this Early Jurassic aeolian system related to multiple factors of groundwater expulsion, timing and local host sediment properties that influenced pipe development. Although the pipe features might be easily overlooked as a smaller scale feature of soft‐sediment deformation in dune deposits, these are valuable environmental indications of disrupted fluid pathways within porous, reservoir quality sands, associated with possible combinations of periodic springs, high water‐table conditions and strong ground‐motion events. These pipe examples may be important analogues where exposures are not so clear, with applications to diverse modern and ancient clastic settings internationally on Earth as well as in planetary explorations such as on Mars.

A brief review on 7 papers from the special issue of “The environmental significance of soft-sediment deformation” of the Sedimentary Geology 344 (2016)

From the viewpoint of origins of soft-sediment deformation structures (SSDS), 7 papers (Ito et al., 2016; Jiang et al., 2016; Lunina and Gladkov, 2016; Moretti et al., 2016; Rana et al., 2016; Rodríguez-Pascua et al., 2016; Wheatley et al., 2016) selected from the special issue of “The environmental significance of soft-sediment deformation” of the Sedimentary Geology 344 (2016) were reviewed. (1) The first paper (according to the published order) by Moretti et al. is a general review and introduction of this special issue. This special issue has made an important contribution to the study of sedimentary environments. (2) The fourth paper by Rodríguez-Pascua et al. is an excellent case study. All evidence of earthquake in this paper is reliable. The old Roman City (adjacent to Madrid, the capital of Spain) was definitely destroyed by an earthquake. This paper solved the problem that the archaeologists have not solved yet. (3) The 19th paper by Rana et al. is another excellent case study. It demonstrated that SSDS in the youngest modern sediments in the seismically active area, i.e., the Alaknanda Valley, Garhwal Himalaya, India, are of non-seismic origin, but with typically sedimentary origin. All evidence of sedimentary origin of SSDS in the study area is reliable. (4) The second paper by Lunina and Gladkov stated that SSDS (mainly clastic dikes) in epicentral areas of the recent earthquakes in southern Siberia were originated by earthquakes and that the clastic dikes are the most reliable indicators in the epicentral areas of earthquakes. This conclusion is right. However, it is not accurate to consider all clastic injections as “in-situ earthquake structures” in anywhere, because the clastic injections are with multiple origins. (5) The third paper by Wheatley et al. comprehensively stated the clastic pipes of the Jurassic in the Colorado Plateau, USA. However, the principal origin of the clastic pipes (columns) was possibly not originated by “palaeoseismic controls”, but by “tectonic controls” or “tectonic uplifts”. (6) The 10th paper by Jiang et al. proposed that 6 types of SSDS of the Lixian Section in eastern Tibetan Plateau, i.e., in a tectonically and seismically active area, were originated by earthquakes. However, the evidence of seismic origin is not sufficient. Therefore, the origins of SSDS in the Lixian Section are worthy to be further discussed. (7) The “injectites” and “extrudites” in a Late Pliocene basin on the Boso Peninsula, Japan, from the 24th paper by Ito et al., are non-SSDS and their origin is unreliable.The above viewpoints may be inappropriate. Criticisms and corrections are welcome.This paper is not only the author's brief review on 7 papers selected from the special issue of the Sedimentary Geology 344 (2016), but also an invitation to geologists worldwide to write papers for a new special issue of “The origins of SSDS” of the Journal of Palaeogeography which is planned to be published in 2018.

Clastic pipe characteristics and distributions throughout the Colorado Plateau: Implications for paleoenvironment and paleoseismic controls

Clastic pipes occur throughout much of the Phanerozoic strata of the Colorado Plateau and provide a unique opportunity to test the validly of various deformation and triggering mechanism hypotheses in the context of their tectono-stratigraphic and paleoenvironmental settings. Pipes dominantly occur in Jurassic strata and preferentially in eolian (especially interdune), sabkha, and fluvial deposits because these sediments contained interbedded fine-grained and water-saturated, high-porosity, coarse-grained facies. The greatest geographic concentrations of pipes occur in three trends: (1) a northeast trend from the Lake Powell to Moab areas of southern and southeastern Utah, (2) an east–west trend in northern Arizona within and north of the Grand Canyon, and (3) a west-northwest–east-southeast trend along Interstate 40 west of Albuquerque, New Mexico. Many pipes formed due to liquefaction and fluidization and were potentially triggered by seismic activity originating from basement-cored uplifts within the Colorado Plateau, although other trigger mechanisms cannot be completely eliminated. Some breccia pipes within northern Arizona that are rooted in karst are the exception to this interpretation. Pipes possess unique depositional and triggering requirements and thus provide an excellent opportunity to understand the interplay of sedimentology and tectonics within continental systems.

Seismogenically induced fluidization of Jurassic erg sands, south‐central Utah

Large bodies of fluidized sandstone occur in the Jurassic Entrada, Carmel, Page and Navajo Formations at several locations in south‐central Utah. They are most abundant in the Entrada Sandstone, where they commonly occur in clusters, have a cylindrical form and have a sharp contact with their cross‐bedded host rock. These clastic pipes are as wide as 75 m and have exposed heights of as much as 100 m. Some of the Entrada pipes extend well into the underlying Carmel redbeds. Other clastic pipes in the Entrada Sandstone are less deformed and display various degrees of brittle‐to‐hydroplastic deformation and liquefaction. Clastic pipes in the Page and Navajo Sandstones are less common, but are similar in size and form to those in the Entrada and Carmel, and probably have a similar origin. Some massive sandstone bodies are irregular in form and have tongue‐like projections into the host rock, implying forcible injection of fluidized sand. Several pipe–host contacts in the Entrada Sandstone display small‐scale ring faults. Where relative displacement can be clearly demonstrated, pipe sandstones are invariably down‐faulted, locally as much as 5 m. At two sites, Carmel host rock is upwarped around the Entrada pipes. Stratified and cross‐bedded breccia blocks occur in many Entrada pipes, and preliminary petrographic analysis indicates that at least some of these breccia blocks are derived from the host rock. Homogeneous pipe sandstones are also petrographically similar to their Entrada host rock, suggesting that some pipes originate through fluidization of the fine‐grained Entrada. Fluidization of the Entrada must have occurred in a water‐saturated environment during early diagenesis but before complete lithification, most probably under considerable porewater pressure. Although there are no known modern analogues to these huge masses of structureless sandstone, they may have a small‐scale modern counterpart in earthquake‐induced sandblows. These features were most probably caused by large‐magnitude seismic events during the Middle Jurassic, although other possibilities cannot be ruled out at this point.

Conical sandstone landforms cored with clastic pipes in Glen Canyon National Recreation Area, southeastern Utah

Clusters of conical sandstone landforms, many with summit weathering pits, have developed on barren outcrops of the Jurassic Entrada Sandstone in Glen Canyon National Recreation Area, southeastern Utah. The conical landforms have developed on cylindrical bodies of fluidized sandstone (clastic pipes) that typically have near-vertical contacts with the enclosing cross-bedded, eolian sandstone. These landforms vary in size and shape due chiefly to differential erosion of the clastic pipe relative to the enclosing sandstone. The greater resistance to weathering of the clastic pipes is due in part to their higher content of calcite cement. Conical, pipe-cored landforms develop progressively from low domes to cones as high as 70 m. Some of the clastic pipes have relatively soft cores and resistant contacts, leading to the development of conical landforms with summit weathering pits. With time, the size of these pits increases as does the relief of the conical landform. The summit pits are as deep as 16 m and have width–depth ratios as low as 1.5. The resistant rims of these pits are due in part to calcite-enriched pipe contacts. Sandy pit-floor sediment is removed principally by strong wind rotors and vortices. Intense eolian activity in and near the landforms is indicated by abrasional features and pit-floor sand dunes. Factors that promote the development of these conical landforms include (i) the presence of clastic pipes, some with relatively soft cores; (ii) porous, friable, fine-grained pipe and host sandstones; (iii) aridity; (iv) strong winds; and (v) virtually sediment-free, unvegetated bedrock outcrops.