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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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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Late Paleozoic Evolution of the Anadarko Basin: Implications for Laurentian Tectonics and the Assembly of Pangea

Abstract Interplay between marginal and intraplate late Paleozoic tectonics in southeastern Laurentia is a subject of debate. In southern Laurentia, intraplate deformation has been attributed to combinations of compressive forces from orogenic belts in the west, southwest, and southeast. While left‐lateral transpression is generally an accepted mechanism for formation of uplifts in the Southern Oklahoma Aulacogen (SOA), to date no studies have explained the driving mechanisms of these kinematics. Here, we analyze the Southern Oklahoma Transpressional System (SOTS), a ∼500 km long ∼50 km wide fault zone that extends from the southeastern Laurentian margin into the plate interior along Cambrian lithospheric weaknesses inherited from the SOA. We use a compilation of published studies to present detailed, time‐integrated sedimentary thickness maps of SOTS‐related basins. We combine these maps with a new interpretation of three 2D seismic reflection lines to constrain timing and kinematics of all major late Paleozoic SOTS fault zones. We show that the SOTS kinematics evolved from contraction to left‐lateral strike‐slip during Mississippian‐Pennsylvanian time. Tectonic activity and fault kinematics in the SOTS are explained by a model in which a remnant ocean basin closed diachronously from northeast to southwest along the Southern Appalachian and Ouachita‐Marathon orogens. Left‐lateral transpression during diachronous closure of the Rheic oceanic basin along the Ouachita‐Marathon margin is related to rotation of the stress field due to changes in slab‐pull and eastward drift of Laurentia toward Gondwana. We speculate that the SOTS acted in part as a STEP (subduction‐transfer edge propagator) fault that followed the pre‐existing SOA.

Hobbs, Noah. F.↗
NASA NTRS1987

A comparative study of diversification events: the early Paleozoic versus the Mesozoic

We compare two major long-term diversifications of marine animal families that began during periods of low diversity but produced strikingly different numbers of phyla, classes, and orders. The first is the early-Paleozoic diversification (late Vendian-Ordovician; 182 MY duration) and the other the Mesozoic phase of the post-Paleozoic diversification (183 MY duration). The earlier diversification was associated with a great burst of morphological invention producing many phyla, classes, and orders and displaying high per taxon rates of family origination. The later diversification lacked novel morphologies recognized as phyla and classes, produced fewer orders, and displayed lower per taxon rates of family appearances. The chief difference between the diversifications appears to be that the earlier one proceeded from relatively narrow portions of adaptive space, whereas the latter proceeded from species widely scattered among adaptive zones and representing a variety of body plans. This difference is believed to explain the major differences in the products of these great radiations. Our data support those models that hold that evolutionary opportunity is a major factor in the outcome of evolutionary processes.

NASA Discipline Exobiology↗
DOE OSTI2022

Synthesis of high-density olivine LiFePO 4 from paleozoic siderite FeCO 3 and its electrochemical performance in lithium batteries

The lithium-ion cathode material olivine LiFePO 4 (LFP) has been synthesized for the first time from natural paleozoic iron carbonate (FeCO 3 ). The ferrous carbonate starting material consists of the mineral siderite at about 92 wt. % purity. Because FeCO 3 has divalent iron, the reaction with lithium dihydrogen phosphate (LiH 2 PO 4 ) provides a unique method to develop iron-(II) containing LFP in an inert atmosphere. Since siderite FeCO 3 is a common mineral that can be directly mined, it may, therefore, provide an inexpensive route for the production of LFP. After carbon-coating, the LFP yields a capacity in the range of 80–110 mAh g -1 LFP (in one chosen specimen sample), which is lower than commercially available LiFePO 4 (150–160 mAh g -1 LFP ). However, the tap density of LFP derived from siderite is noticeably high at 1.65 g cm -3 . The material is likely to be improved with powder purification, nanosized processing, and more complete carbon-coating coverage with increased optimization.

36 MATERIALS SCIENCE↗
NASA NTRS1987

Environmental trends in extinction during the Paleozoic

Extinction intensities calculated from 505 Paleozoic marine assemblages divided among six environmental zones and 40 stratigraphic intervals indicate that whole communities exhibit increasing extinction offshore but that genera within individual taxonomic classes tend to have their highest extinction onshore. The offshore trend at the community level results from a concentration of genera in classes with low characteristic extinction rates in nearshore environments. This finding is consistent with the ecologic expectation that organisms inhabiting unpredictably fluctuating environments should suffer more extinction than counterparts living under more predictably equitable conditions.

Sepkoski, J. John, Jr.↗
NASA NTRS2000

Competitive displacement among post-Paleozoic cyclostome and cheilostome bryozoans

Encrusting bryozoans provide one of the few systems in the fossil record in which ecological competition can be observed directly at local scales. The macroevolutionary history of diversity of cyclostome and cheilostome bryozoans is consistent with a coupled-logistic model of clade displacement predicated on species within clades interacting competitively. The model matches observed diversity history if the model is perturbed by a mass extinction with a position and magnitude analogous to the Cretaceous/Tertiary boundary event, Although it is difficult to measure all parameters in the model from fossil data, critical factors are intrinsic rates of extinction, which can be measured. Cyclostomes maintained a rather low rate of extinction, and the model solutions predict that they would lose diversity only slowly as competitively superior species of cheilostomes diversified into their environment. Thus, the microecological record of preserved competitive interactions between cyclostome and cheilostome bryozoans and the macroevolutionary record of global diversity are consistent in regard to competition as a significant influence on diversity histories of post-Paleozoic bryozoans.

NASA Discipline Exobiology↗
DOE OSTI2017

Isotopically zoned carbonate cements in Early Paleozoic sandstones of the Illinois Basin: δ 18 O and δ 13 C records of burial and fluid flow

SEM/SIMSimaging andanalysis of δ 18 O and δ 13 C in sandstonesfrom a transect through the Illinois Basin(USA) show systematic μm-scale isotopic zonation of up to 10‰ in both carbonate and quartzcements of the middle-Ordovician St. Peter and Cambrian Mt. Simonformations. Quartz δ 18 O values are broadly consistent with the model of Hyodo et al. (2014), wherein burial and heating in the Illinois Basinis recorded insystematically zonedquartz overgrowths. Observations of zoned dolomite/ankerite cements indicate that they preserve a more extended record of temperature and fluid compositionsthan quartz, including earlydiagenesis before orduring shallow burial,and late carbonates formed after quartzovergrowths. Many carbonate cements show innermostdolomite withδ 18 O values (21-25‰ VSMOW) that are too low to have formed by depositionat low temperatures from ancient seawater(δ 18 O>-3‰)and most likelyreflect mixing with meteoric water. A sharp increase in Fe content is commonly observed in zoned carbonate cements to be associated with a drop in δ 18 O and an abrupt shift in δ 13 C to higher or lower values. These changes are interpreted to record the passage of hot metal-richbrinesthrough sandstone aquifers,that wasassociated with Mississippi-Valley Type (MVT) Pb-Zn deposits (ca. 270 Ma) of the Upper Mississippi Valley. Local variability and individual trends in δ 13 Care likely controlled by the sources of carbon and the degree to which carbonis sourced fromadjacent carbonate units or thermal maturation of organic matter. Quartz overgrowths in sandstones provide an excellent record of conditions during burial, heating, and pressure-solution, whereas carbonate cements in sandstonespreserve a more-extendedrecord includinginitial pre-burial conditions and punctuated fluid flowevents.

58 GEOSCIENCES↗
NASA NTRS1971

New pre-Paleozoic nannofossils from the Stoer Formation /Torridonian/, northwest Scotland.

The nature of the sph eroidal unicellular fossils 10 to 62 micrometers in diameter that are abundant in black shales referred to the Stoer Formation of lower Torridonian age at Stoer Bay, in northwest Scotland, is examined. It is shown that their biological affinities are obscure; it is, however, not unlikely that many or most of them are independent unicellular members of the marine phytoplankton.

Cloud, P.↗