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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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406 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Field Geologic Mapping of Sample Sites From the Ground and the Air With Perseverance Rover and Ingenuity Helicopter

One of the primary mission goals for Perseverance is to determine the geologic context of sample sites. Rover-based (in situ) or field geologic context mapping (GXM) based on Perseverance rover and Ingenuity helicopter observations provides a nearly continuous record of geologic context and exposed surface structure over a 120 m-wide corridor along the traverse of Perseverance and the flight path of Ingenuity. Field geologic mapping along the traverse and flight path and outcrop-scale mapping at sample sites provides a spatial dimension to ground truth geologic, stratigraphic, and modern environmental context for samples at scales relevant to sample interpretation. Here we provide an abbreviated overview of field mapping as it relates to documenting the architecture of the Jezero fan and geologic context of several examples of sample locations.

Mars 2020↗
NASA NTRS2024

What Are the Olivine-Rich Boulders in the Upper Fan and Margin Unit at Jezero Crater, Mars?

Since February 2021, the Perseverance rover has explored Jezero Crater in the Nili Fossae region of Mars which hosts large outcrops of a regional olivine-carbonate unit. In the crater floor, Perseverance investigated two igneous formations: Máaz, composed of basaltic lava and/or pyroclastic flows, and Séítah, an olivine-rich cumulate] below Máaz. Then, Perseverance explored the western fan composed by diverse sedimentary rocks of variable composition, but often containing olivine On the upper fan and margin unit, Perseverance encountered number of centimetric to metric boulder rocks. Two main types of boulders were identified based on texture and composition: the olivine-rich and pyroxene-bearing boulders. Here, we use SuperCam data to describe the texture, geochemistry and mineralogy of the olivine-rich boulders. Then, we discuss their possible petrological origin and some possible implications for the regional Nili Fossae olivine-carbonate unit.

Mars 2020↗
DOE OSTI2017

Evidence of a Sandy Suspended-Load Dominated River from the Mississippian Cypress Formation, Illinois, USA

Describes how diagnostic sedimentary facies and textures have been identfied by integrating new core and outcrop data, which enabled a new interpretation for the thick sandstones within the Cypress Formation as meandering or anastomosing fluvial deposits. The results provide new insight into the preservation of mesoforms and macroforms under the influence of suspended-load dominated transport as well as implications for the dynamics of Carboniferous continental scale river systems in the Illinois Basin.

Howell, Kalin↗
DOE OSTI2020

Characterizing natural fractures and sub-seismic faults for well completion of Marcellus shale in the MSEEL Consortium project, West Virginia, USA

The Middle Devonian Marcellus shale play has emerged as a major world-class hydrocarbon accumulation and represents one of the largest and most prolific shale plays in the world. According to many outcrop studies in the region, natural fractures are well developed in the Marcellus Shale. However, evaluating fractures in the subsurface is often a significant challenge due to a lack of sufficient data. Therefore, in the Marcellus Shale Energy and Environment Laboratory (MSEEL) consortium project, significant efforts have been made to acquire high-quality image logs in the Marcellus laterals. The project provided tremendous opportunities to characterize the natural fractures and sub-seismic faults and to evaluate their impact on well stimulation. In this study, about 70,000 ft of acquired high-resolution logging while drilling (LWD) acoustic images from five long laterals located in Monongalia County, West Virginia, were processed and interpreted. In addition, the study used high-quality micro-resistivity images from a pilot well, allowing the evaluation of natural fractures in the entire Marcellus vertical sequence. Based on the available acoustic images, the natural fractures were classified into three basic categories: high-amplitude fractures, low-amplitude fractures, and faults. Further, larger open fractures can also be determined when a low-amplitude fracture is evident on caliper images. The fractures in the Marcellus usually have a medium to high angle dip; however, multiple fracture sets in terms of strike orientation were clearly observed in all the laterals. The fracture set with a strike at NE-SW (or 60-240 deg) seems to be the predominant one in all the wells. A few other sets, including those with N-S, NWW-SEE, and E-W strikes, were also observed. Several sub-seismic faults, with mostly a low dip angle and a NE-SW strike, have also been seen in two of the laterals. The fracture density is variable across all the laterals, ranging from very low (or none) to very high (up to 5 fractures per ft). The average fracture density for all the laterals is about 1 fracture per 10 ft. In the vertical sequence, the natural fracture development showed a clear preference for shale or shaly facies over carbonate-rich or thin limestone layers. The interpreted fracture and fault data were used as input data for the stimulation design with the purpose of better understanding the fractures’ impact on well stimulation. Production data from the laterals were also used to evaluate the natural fractures’ influence on well performance. The quality image database and the consistent interpretation results for the entire project enabled a systematic approach to characterizing fractures and, more importantly, to evaluating the impact of fractures on well stimulation and production.

03 NATURAL GAS↗
DOE OSTI2021

Combined Structural Analysis of Core and Image Log of TGH 76-31 South East of Mt Baker, Washington State

Despite active volcanism, few geothermal energy resources have been developed in the Cascades Range. Temperature Gradient Hole 76-31 was drilled to ~440 m measured depth to probe for zones where fractures provide fluid conduits that transport deep volcanic heat to shallow depths that could support baseload, carbon neutral electrical generation. These zones were predicted by a Play Fairway assessment (PFA) of resource potential along a zone 11 km west-southwest of the summit of Mount Baker Volcano. Rock core, temperature logs, and an acoustic image log were obtained. By comparison to outcrops, the core has been initially interpreted as the Chilliwack group comprised of partially metamorphosed basaltic to andesitic volcanics. Core mapping reveals complex, steeply dipping networks of fractures and brecciation along slickensided strike slip faults; clay alteration is common in many of these structures. The majority of fractures are thoroughly healed by layers of chlorite and calcite; preservation of pyrite indicates anoxic conditions. The majority of fracture porosity resides in very dense fractures a few centimeters or less in length. The image log provides good insights into attitude of fractures that fully transect the core, but generally underestimates fracture density. The combination of complex, non-planar fracture zones containing many short fractures and healing promote misinterpretation of natural fracture attitude and density in the image log. The healing and anoxic minerals are consistent with the conductive temperature gradient measured in the well below a shallow isothermal zone, although, several fractures are open or only partially healed and resulted in fluid entries into the well. Here, the equilibrated measured temperature gradient of 64ºC/km and calculated heat flow of 145 mW/m2 is more than twice the regional average, indicating local influence of the Mt Baker magmatic system at the Little Park Creek TGH site.

Cascades↗
DOE OSTI2018

Natural Attenuation Progress, Plume Movement, and Source Reduction for the SRS CMP Pits VOC Plume - 18384

Monitoring the effectiveness of natural attenuation for remediating the Savannah River Site (SRS) Chemical, Metals, and Pesticides (CMP) Pits plume fringe has focused intensive sampling of shallow groundwater for different reaches of Pen Branch from 2005 to 2017. Volatile organic compounds (VOCs) were analyzed for the critical hyporheic zone beneath Pen Branch and adjacent floodplain. These sampling efforts assisted larger-scale compliance monitoring in accordance with US Environmental Protection Agency (EPA) guidelines. When applicable, EPA has found natural attenuation to be an acceptable mode of achieving regulatory compliance. While natural attenuation can include any ecosystem function that reduces contaminant loads, it is focused on microbial biochemical pathways. The study plume originated from CMP Pits, a waste disposal area in operation from 1971 to 1979, when the pits were closed and backfilled. In 1984, excavations of source material and contaminated soils were removed up to a depth of 7.6 m below the trenches. However, monitoring well data indicated that perchloroethylene (PCE) and trichloroethylene (TCE) had seeped beneath the vadose zone and formed groundwater plumes reaching the Pen Branch valley below. Although 'hot spots' of TCE were found within the Pen Branch floodplain, it was unknown just how the flow pattern was entering Pen Branch and to what degree natural attenuation was reducing the contaminant load. For this reason, our stations were located along the Pen Branch reach bordering the modelled plume fringe. In general, VOCs were highest at station piezometer holes in the middle study zone. Moderate VOC levels were detected at upstream stations and lowest VOC levels were found at downstream stations. Electrical resistance heating (ERH) with soil vapor extraction (SVE) conducted by Savannah River Nuclear Solutions (SRNS) from 2008 to 2009 at the filled CMP Pits helped to remove contaminants trapped in clay horizons beneath the CMP Pits and to reduce overall new plume concentrations. Collectively PCE, TCE, and their degradation products displayed a favorable yearly trend of contaminant natural attenuation. Additionally, phytoremediation actions by native bamboo, Arundinaria gigantea, added to VOC removal from wetlands soils. Total VOC concentrations at some stations declined by >25% and concentrations of vinyl chloride (VC), a nearly-final stage degradation product increased from 0.0 ppb to >20 ppb. Temporal patterns displayed a continued reduction of VOCs, while spatial patterns indicated a possible slow progression of the plume downstream along Pen Branch. Conclusions about plume export into surface waters must address the seasonal and geological complexities of this system. Hydrological patterns are complex and plumes do not directly outcrop into Pen Branch surface waters, but emerge into the stream through pathways in the porous hyporheic zone. For this reason, continued sampling must identify critical depths and downstream locations where plume flows may be more intense. During drought periods with no surface flow in Pen Branch, subsurface plume flows may be flowing downslope in the hyporheic zone. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Historical Savannah River Site Tritium Releases, Pathways, and Transport

† Releases of tritium from the production reactors were due almost entirely to releases of moderator, either as liquid or vapor from the reactor systems and from the heavy water rework facility. Small amounts could have been released from the reactor blanket gas system and from irradiated lithium-bearing control rods and targets stored underwater in the disassembly basins (Longtin et al. 1973; Jacober et al. 1973). ‡Only a part of the tritium released to the seepage and retention basins leave the site. Of the 3,015,000 Ci of tritium released to the basins, 27% (0.81M Ci) evaporated from the basin surfaces, 40% (1.2M Ci) migrated to outcrops and entered surface streams, and 33% (0.99M Ci) remains under the basins.

Chiswell, Steven R.↗
DOE OSTI2022

From Lake to River: Documenting an Environmental Transition Across the Jura/Knockfarril Hill Members Boundary in the Glen Torridon Region of Gale Crater (Mars)

Between January 2019 and January 2021, the Mars Science Laboratory team explored the Glen Torridon (GT) region in Gale crater (Mars), known for its orbital detection of clay minerals. Mastcam, Mars Hand Lens Imager, and ChemCam data are used in an integrated sedimentological and geochemical study to characterize the Jura member of the upper Murray formation and the Knockfarril Hill member of the overlying Carolyn Shoemaker formation in northern GT. The studied strata show a progressive transition represented by interfingering beds of fine–grained, recessive mudstones of the Jura member and coarser–grained, cross–stratified sandstones attributed to the Knockfarril Hill member. Whereas the former are interpreted as lacustrine deposits, the latter are interpreted as predominantly fluvial deposits. The geochemical composition seen by the ChemCam instrument show K 2 O–rich mudstones (~1–2 wt.%) versus MgO–rich sandstones (>6 wt.%), relative to the average composition of the underlying Murray formation. We document consistent sedimentary and geochemical data sets showing that low–energy mudstones of the Jura member are associated with the K–rich endmember, and that high–energy cross–stratified sandstones of the Knockfarril Hill member are associated with the Mg–rich endmember, regardless of stratigraphic position. The Jura to Knockfarril Hill transition therefore marks a significant paleoenvironmental change, where a long–lived and comparatively quiescent lacustrine setting progressively changes into a more energetic fluvial setting, as a consequence of shoreline regression due to either increased sediment supply or lake–level drop.

58 GEOSCIENCES↗
DOE OSTI2018

Elevation Grid for top Columbia River Basalt (CRBG) in the Portland Basin used in DDU Feasibility Study

The Portland Basin is a prime location to assess the feasibility of DDU-TES because natural geologic conditions provide thermal and hydraulic separation from overlying aquifers that would otherwise sweep away stored heat. Under the Portland Basin, the lower Columbia River Basalt Group (CRBG) aquifers contain brackish water (1,000-10,000 mg/L TDS), indicating low groundwater flow rates and poor connection with the overlying regional aquifer. Further, CRBG lavas tend to have comparatively low thermal conductivity, indicating that the 400-1,000 ft thick CRBG may be an effective thermal barrier to the overlying aquifer. A temporally and spatially limited previous study of a Portland Basin CRBG aquifer demonstrated that the injection of waste heat resulted in an increase in temperature by more than a factor of two, indicating a high potential for storing heat. This data submission includes ASCII grid surfaces for the Portland and Tualatin Basins including a DEM of modern topography, the top of Columbia River Basalt (CRB), the base of CRB, and basement. It also includes three isochore (thickness) maps between these intervals. In addition, there is an ArcGIS attribute table for associated data points, a map of data types used to constrain the top of CRB, and cross-sections, all made using IHS Kingdom Suite, Petrosys PRO, ESRI ArcGIS, and Adobe Illustrator software.

15 GEOTHERMAL ENERGY↗