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Academic literature on the topic 'Crustal Correlation'

Author: Grafiati

Published: 6 September 2023

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Journal articles on the topic "Crustal Correlation"

1

Okaya, David A., and Craig M. Jarchow. "Extraction of deep crustal reflections from shallow Vibroseis data using extended correlation." GEOPHYSICS 54, no. 5 (May 1989): 555–62. http://dx.doi.org/10.1190/1.1442682.

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Lower crustal seismic reflections can be extracted from shallow crustal seismic profiles through the application of extended correlation to uncorrelated Vibroseis seismic data. “Fixed‐bandwidth” extended correlation shortens the correlation operator before crosscorrelation, producing reflections over an increased correlation time range, all with lowered bandwidth. “Self‐truncating” extended correlation preserves the full bandwidth in the original seismic reflection times but loses bandwidth in a predictable manner at the additional (later) arrival times. Correlation wavelet shape and extra correlation time are directly related and can be calculated for specific acquisition parameters. Pre‐correlation tapering is necessary to avoid undue wavelet distortion at extended correlation times. Seismic data collected in the Basin and Range province illustrate the application of the method; the results are verified with conventional correlations of long sweep records and with impulsive source data.

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Moore, Eli K., Daniella L. Martinez, Naman Srivastava, Shaunna M. Morrison, and Stephanie J. Spielman. "Mineral Element Insiders and Outliers Play Crucial Roles in Biological Evolution." Life 12, no. 7 (June 24, 2022): 951. http://dx.doi.org/10.3390/life12070951.

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The geosphere of primitive Earth was the source of life’s essential building blocks, and the geochemical interactions among chemical elements can inform the origins of biological roles of each element. Minerals provide a record of the fundamental properties that each chemical element contributes to crustal composition, evolution, and subsequent biological utilization. In this study, we investigate correlations between the mineral species and bulk crustal composition of each chemical element. There are statistically significant correlations between the number of elements that each element forms minerals with (#-mineral-elements) and the log of the number of mineral species that each element occurs in, and between #-mineral-elements and the log of the number of mineral localities of that element. There is a lesser correlation between the log of the crustal percentage of each element and #-mineral-elements. In the crustal percentage vs. #-mineral-elements plot, positive outliers have either important biological roles (S, Cu) or toxic biological impacts (Pb, As), while negative outliers have no biological importance (Sc, Ga, Br, Yb). In particular, S is an important bridge element between organic (e.g., amino acids) and inorganic (metal cofactors) biological components. While C and N rarely form minerals together, the two elements commonly form minerals with H, which coincides with the role of H as an electron donor/carrier in biological nitrogen and carbon fixation. Both abundant crustal percentage vs. #-mineral-elements insiders (elements that follow the correlation) and less abundant outsiders (positive outliers from the correlation) have important biological functions as essential structural elements and catalytic cofactors.

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Candia, Gabriel, Alan Poulos, Juan Carlos de la Llera, Jorge G. F. Crempien, and Jorge Macedo. "Correlations of spectral accelerations in the Chilean subduction zone." Earthquake Spectra 36, no. 2 (February 2, 2020): 788–805. http://dx.doi.org/10.1177/8755293019891723.

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The correlation between spectral accelerations is key in the construction of conditional mean spectra, the computation of vector-valued seismic hazard, and the assessment of seismic risk of spatially distributed systems, among other applications. Spectral correlations are highly dependent on the earthquake database used, and thus, region-specific correlation models have been developed mainly for earthquakes in western United States, Europe, Middle East, and Japan. Correlation models based on global data sets for crustal and subduction zones have also become available, but there is no consensus about their applicability on a specific region. This study proposes a new correlation model for 5% damped spectral accelerations and peak ground velocity in the Chilean subduction zone. The correlations obtained were generally higher than those observed from shallow crustal earthquakes and subduction zones such as Japan and Taiwan. The study provides two illustrative applications of the correlation model: (1) computation of conditional spectra for a firm soil site located in Santiago, Chile and (2) computation of bivariate hazard for spectral accelerations at two structural periods.

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Yan, Yuping, Paul A. Mayewski, Shichang Kang, and Eric Meyerson. "An ice-core proxy for Antarctic circumpolar zonal wind intensity." Annals of Glaciology 41 (2005): 121–30. http://dx.doi.org/10.3189/172756405781813294.

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AbstractUsing US National Centers for Environmental Prediction/US National Center for Atmospheric Research re-analysis data, we investigate the relationships between crustal ion (nssCa2+) concentrations from three West Antarctic ice cores, namely, Siple Dome (SD), ITASE00-1 (IT001) and ITASE01-5 (IT015), and primary components of the climate system, namely, air pressure/geopotential height, zonal (u) and meridional (v) wind strength. Linear correlation analyses between nssCa2+ concentrations and both air-pressure and wind fields for the period of overlap between records indicate that the SD nssCa2+ variation is positively correlated with spring circumpolar zonal wind, while IT001 nssCa2+ has a positive correlation with circumpolar zonal wind throughout the year (r > 0.3, p < 0.01). Intensified Southern Westerlies circulation is conducive to transport of more crustal aerosols to both sites. Further correlation analyses between nssCa2+ concentrations from SD and IT001 and atmospheric circulation suggest that the high inland plateau (represented by core IT001) is largely influenced by transport from the upper troposphere. IT015 nssCa2+ is negatively correlated with westerly wind in October and November, suggesting that stronger westerly circulation may weaken the transport of crustal species to IT015. Correlations of nssCa2+ from the three ice cores with the Antarctic Oscillation index are consistent with results developed from the wind-field investigation. In addition, calibration between nssCa2+ concentration and the multivariate El Niño–Southern Oscillation (ENSO) index shows that crustal species transport to IT001 is enhanced during strong ENSO events.

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Bursnall, J. T., A. D. Leclair, D. E. Moser, and J. A. Percival. "Structural correlation within the Kapuskasing uplift." Canadian Journal of Earth Sciences 31, no. 7 (July 1, 1994): 1081–95. http://dx.doi.org/10.1139/e94-097.

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Comparison of progressive deformation and metamorphic history within and between the tectonic domains of the Kapuskasing uplift indicates significant variation in age and style of deformation across this large segment of the central Superior Province; multiple stages of tonalite and granitoid intrusion, melt generation, polyphase diachronous deformation, and likely rapid deep burial of supracrustal rocks collectively produced the complex character of this example of Archean mid to deep crust. At least four Archean deformation phases are recognized, although not all are of regional extent. Dated structural chronology suggests that the locus of the earliest recorded deformations migrated to deeper crustal levels with time. Pre-2680 Ma deformation (local D1–D2) within high-level tonalites is correlated with deformation in the Michipicoten supracrustal belt. The apparent earliest deformational fabrics at deeper crustal levels in the granulite terrane of the Kapuskasing structural zone occurred between 2660 and 2640 Ma. Archean third and fourth phase deformation phases (~ 2667 to ~ 2629 Ma) are present at mid-crustal and deeper levels and deform post-2667 Ma metaconglomerate; these resulted in large-scale folding and subhorizontal ductile shear zones, which seem to represent an important transitional zone that separated a passive upper crust from continued ductile strain at deeper levels.Subsequent uplift of the high-grade rocks was accomplished in multiple stages, initiated prior to 2.45 Ga and likely culminated around 1.9 Ga, although continued movement occurred as late as 1.14 Ga. The Ivanhoe Lake fault zone, along which much of the uplift must have occurred, exhibits some evidence of ductile deep-thrust-related fabrics, but most of the observed structures are brittle to brittle–ductile and steeply inclined. A broad zone of pervasive cataclasis and brittle–ductile shear zones is a characteristic feature of the fault zone throughout its length, and both dextral and sinistral offset are locally present. Clear ground evidence for major transcurrent or thrust displacements, however, has not been recognized.

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Bodri, L., and B. Bodri. "On the correlation between heat flow and crustal thickness." Tectonophysics 120, no. 1-2 (November 1985): 69–81. http://dx.doi.org/10.1016/0040-1951(85)90087-3.

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Rindraharisaona, E. J., F. Tilmann, X. Yuan, G. Rümpker, J. Giese, G. Rambolamanana, and G. Barruol. "Crustal structure of southern Madagascar from receiver functions and ambient noise correlation: Implications for crustal evolution." Journal of Geophysical Research: Solid Earth 122, no. 2 (February 2017): 1179–97. http://dx.doi.org/10.1002/2016jb013565.

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Kim, Jeong Woo, Ralph R. B. von Frese, and Hyung Rae Kim. "Crustal modeling from spectrally correlated free‐air and terrain gravity data—A case study of Ohio." GEOPHYSICS 65, no. 4 (July 2000): 1057–69. http://dx.doi.org/10.1190/1.1444799.

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We investigate the use of spectral correlation theory to analyze terrain gravity effects and free‐air gravity anomalies of Ohio for possible constraints on the thickness variations and neotectonics of the crust. Terrain gravity effects are computed from the topography by Gauss‐Legendre quadrature integration and are compared against independent free‐air gravity anomaly observations for their wavenumber correlation spectrum. Spectral correlation filters are designed accordingly to extract terrain‐correlated free‐air gravity anomalies that are subtracted from the terrain gravity effects for estimates of the compensated terrain gravity effects. These effects are used to model the Moho by inversion, assuming they predominantly reflect crustal thickness variations. Our results characterize the middle third of Ohio as a broad zone of thickened Precambrian crust, which also may include rifted regions where the thickness of the prerift crust has been reduced greatly. Furthermore, we find that about 83% of the instrumentally determined earthquake epicenters are located within the inferred thinner regions of Ohio’s crust or at their margins where compressional stresses may dominate. In general, these crustal thickness variations provide new constraints on modeling the tectonic evolution and geotechnical parameters of the crust—constraints that are important for evaluating earthquake hazards, the distribution and extraction of crustal resources, and the storage of hazardous waste and other crustal engineering applications.

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Kolstrup, M. L., and V. Maupin. "Measuring and crust-correcting finite-frequency travel time residuals – application to southwestern Scandinavia." Solid Earth Discussions 7, no. 3 (July 1, 2015): 1909–39. http://dx.doi.org/10.5194/sed-7-1909-2015.

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Abstract. We present a data processing routine to compute relative finite-frequency travel time residuals using a combination of the Iterative Cross-Correlation and Stack (ICCS) algorithm and the MultiChannel Cross-Correlation method (MCCC). The routine has been tailored for robust measurement of P and S wave travel times in several frequency bands and for avoiding cycle-skipping problems at the shortest periods. We also investigate the adequacy of ray theory to calculate crustal corrections for finite-frequency regional tomography in normal continental settings with non-thinned crust. We find that ray theory is valid for both P and S waves at all relevant frequencies as long as the crust does not contain low-velocity layers associated with sediments at the surface. Reverberations in the sediments perturb the arrival times of the S waves and the long-period P waves significantly, and need to be accounted for in crustal corrections. The data processing routine and crustal corrections are illustated using data from a network in southwestern Scandinavia.

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St-Onge, M. R., D. J. Scott, and N. Wodicka. "Review of crustal architecture and evolution in the Ungava Peninsula — Baffin Island area: connection to the Lithoprobe ECSOOT transect." Canadian Journal of Earth Sciences 39, no. 5 (May 1, 2002): 589–610. http://dx.doi.org/10.1139/e02-022.

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Within the Trans-Hudson Orogen in northern Quebec and southern Baffin Island, parautochthonous Archean basement and Paleoproterozoic cover, as well as allochthonous (accreted) Paleoproterozoic units, are exposed in a series of antiformal culminations and complementary synclinoria. The parautochthonous rocks of the Superior Province margin and two assemblages of accreted Paleoproterozoic units (Ungava and Meta Incognita crustal terranes) define a basic tripartite crustal architecture which is characterized by polyphase deformation and metamorphic histories. Early structures and mineral assemblages are recognized in all three crustal components and shown to be temporally distinct. The earlier structures and assemblages are overprinted by younger elements and mineral assemblages that are related to at least three regional contraction episodes and one thermal event that are common to all crustal components of the orogen. Close correlation of regional aeromagnetic data in northern Quebec and southern Baffin Island with the three crustal components offers a first-order approximation of the distribution of basement lithological units across Hudson Strait. Continuation of the aeromagnetic domains beneath Ungava Bay to northeastern Quebec and northern Labrador allows for the southward extrapolation of the tripartite Trans-Hudson Orogen crustal architecture into the Lithoprobe Eastern Canadian Shield OnshoreOffshore Transect area.

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Dissertations / Theses on the topic "Crustal Correlation"

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Carr, Steve Asamoah Boamah. "Crustal stress changes induced by seasonal hydrological load variations in correlation with seismicity rate changes in the Malawi Rift System." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1621867336511141.

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Saygin, Erdinc, and erdinc saygin@anu edu au. "Seismic Receiver and Noise Correlation Based Studies in Australia." The Australian National University. Research School of Earth Sciences, 2007. http://thesis.anu.edu.au./public/adt-ANU20091009.115242.

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This thesis is directed at exploiting information in the coda of seismic phases and the ambient noise field to provide new constraints on the structure of the Australian Continent. ¶ The exploitation of the immediate coda following the onset of P waves from a distant earthquake using radial receiver functions is now a well established method. The 40 sec interval following P contains reverberations and conversions, by deconvolving the radial component trace with the vertical components, the conversions are emphasized by canceling the part of the response that are common to both components. A member of different styles of such deconvolution, are investigated and a variant of the multitaper method is adopted for subsequent applications. The TASMAL experiment 2003-2005 spans the expected location of the transition between Precambrian and Phanerozoic Australia. The 20 portable broadband stations were exploited in receiver function studies to extract S wave crustal structure through the inversion of stacked receiver functions using the Neighbourhood Algorithm. There is no clear crustal transition associated with the presence of Tasman Line. The Precambrian Cratons tend to exhibit crustal thicknesses close to 40 km but such values are also found in some Phanerozoic sites. ¶ The second part of the thesis is directed at the exploitation of ambient noise or seismic coda to gain information on the Green's function between seismic stations. The TASMAL experiment covered a significant fraction of the Australian continent with a simultaneous deployment of portable broadband stations. From these continuous records, it has proved possible to extract very clear Rayleigh wave signals for station separations up to 2000 km, and to demonstrate the frequency dependent variations in group velocity behaviour. The combination of the paths between the 20 stations localize such behaviour, but detailed images needed more data. The entire archive of portable broadband data recorded by RSES was mined, and combined with data from permanent stations to provide more than 1100 estimates of interstation Green's functions within Australia. Group velocity analysis as function of frequency was followed by nonlinear tomography with the Fast Marching Method. The resulting images of group velocity patterns as a function frequency show pronounced regions of lowered group velocities, most of which match regions of thick sediment. The frequency dependence is not consistent with just sedimentary structure and low midcrustal velocities, most likely due to elevated temperatures, are also needed. ¶ The surface wave portion of the interstation Green's function is the most energetic, and is normally all that seen in ambient noise studies. However, in the coda of events record at the broadband Warramunga seismic array in the Northern Territory, the P and S body wave components also emerge. The characteristics of these arrivals match those observed from nearby small earthquakes. The stacked cross-correlation is the normal approach to enhance Green's function information from ambient noise, but a broader spectral band width with the same phase response can be found by spectral division. It appears advantageous to compare both approaches and select the best result, since very little modifications to procedures are needed. ¶ The properties of the ambient noise at a single station have been investigated in the logarithmic spectral domain and a station dependent signal can be extracted by stacking. The signal appears to be related to the local structure beneath the station, and when fully characterized may provide a new means of investigating structure.

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Becker, Gesa Karen [Verfasser], Brigitte [Akademischer Betreuer] Knapmeyer-Endrun, Ulrich [Gutachter] Christensen, and Laurent [Gutachter] Gizon. "Crustal thickness from seismic noise correlations in preparation for the InSight mission to Mars / Gesa Karen Becker ; Gutachter: Ulrich Christensen, Laurent Gizon ; Betreuer: Brigitte Knapmeyer-Endrun." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1166399753/34.

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Caballero, Suárez Olga Liliana. "Effects of ion correlations in high density plasmas neutrino scattering and transport properties in supernovae and neutron star crusts /." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337248.

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Thesis (Ph.D.)--Indiana University, Dept. of Physics, 2008.
Title from PDF t.p. (viewed on Jul 29, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: B, page: 7583. Adviser: Charles J. Horowitz.

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Thanooja, P. V. "Crustal evolution and tectonic processes of the Madras Block, India." Thesis, 2021. https://etd.iisc.ac.in/handle/2005/5796.

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The Neoarchaean (2.8–2.5 Ga) era in the earth’s history witnessed significant crustal growth related to the amalgamation and dispersion of ancient continents. The processes leading to the formation and destruction of the crust remain enigmatic. Thus, it becomes critical to investigate the Neoarchaean continental crust for understanding these crustal and tectonic processes operated at that time. The crustal blocks which are situated as a transitional zone in between the Southern Granulite Terrane (SGT) and the Dharwar Craton in India, are the well-preserved example of Neoarchaean terranes. The Madras Block is one of the least studied among different crustal blocks in this region. It consists mainly of charnockite, felsic-orthogneiss and meta-monzo-diorite, with a minor occurrence of amphibolite, meta-volcanic, and meta-pelitic rocks. The detailed petrographical, geochemical, and geochronological investigations on these basement rocks pointed out three petrogenetically distinct types (Type-A, -B, and -C) of charnockite from the Madras Block. The Type-A charnockite comprises felsic minerals, minor clinopyroxene and orthopyroxene, abundant biotite, and amphibole. Relative to Type-A charnockite, Type-B, and Type-C, charnockite is rich in garnet and anhydrous ferromagnesium minerals, respectively. Type-A shows a highly depleted HREE pattern ((La/Yb)N = ~36) with a higher degree of chemical fractionation compared to the Type-B ((La/Yb)N ~11) and Type-C ((La/Yb)N ~5). The present results demonstrate that the Type-A charnockite was formed by melting of the subducting oceanic slab and overriding Mesoarchaean proto-crust with a minor input of mantle wedge during 2.79–2.54 Ga. The combined melting of the underplated mantle and overriding Mesoarchean proto-crust along with mixing and homogenisation of Type-A charnockite, during 2.57–2.50 Ga, led to the formation of Type-B and -C charnockite. All the charnockites were subjected to regional metamorphism at ~2.50 Ga, as the prolonged upwelling and magmatism raised the temperature of the entire crust. The felsic-orthogneiss has a highly fractionated REE profile (La/YbN = ~42) resembling Archaean TTG suite of rocks. The meta-monzo-diorite shows a weakly fractionated REE pattern (La/Yb)N = ~17.6) with relatively higher HREE (∑HREE = ~88 ppm) similar to that of Type-B charnockite. The amphibolite which occurs as enclaves, have relatively flat REE pattern, while those occurring as larger volumes (outcrops) have comparatively high LREE. The similar initial 143Nd/144Nd (0.5091–0.5094) and initial 87Sr/86Sr (0.7016–0.7033), along with field and geochemical evidence, suggest that the felsic-orthogneiss and meta-monzo-diorite were formed from the same parental magma (basaltic in affinity) during 2.57–2.51 Ga. The REE geochemical modelling demonstrates a multi-stage magma generation starting from partial melting of a mantle-derived underplated basaltic source, followed by mixing and homogenisation with crustal felsic melt and different rate of continuous fractionation (25-50%) formed ~2.54 Ga felsic and mafic rock in the Madras Block. Thus, the basement rocks of the Madras Block were formed as the result of the repetitive intrusions of basaltic magma into the lower-crust over a long period of time. Consequently, the proto-underplated basaltic magma (~2.62 Ga) be thermally rejuvenated by another pulse of hotter magma and generated ~2.54 Ga felsic-mafic rocks. Synchronous late Neoarchaean magmatic events and associated metamorphism are also identified from the eastern block of the North China Craton (Yishui terrane, Shandong Peninsula), and the north-central Korean Peninsula (Daeijak Island, NW-Gyeonggi Massif). These two terranes and the southern India (Madras Block) demonstrate their close similarities in geological setting, age, petrochemistry, isotopic composition and metamorphic history. Hence, this study proposes that these terranes were once contiguous as part of a Neoarchaean supercontinent.
DST - INSPIRE (IF150424) and DST - SERB project (EMR / 2016 / 003632)

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Becker, Gesa Karen. "Crustal thickness from seismic noise correlations in preparation for the InSight mission to Mars." Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E495-4.

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Ishwar, Kumar C. "Mesoproterozoic Suturing Of Archean Crustal Blocks In Western Peninsular India : New Insights On India-Madagascar Correlations." Thesis, 2015. https://etd.iisc.ac.in/handle/2005/2651.

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The structural lineament mapping of southern India along withgeological, geochronological datasets help in redefining the Precambrian crustal blocks.The newly proposed Kumta and Mercara suture zones welding Archean crustal blocks in western peninsular India offer critical insights into the crustal evolution of Gondwana. The Kumta suturemainly consists of schistose rocks including quartz-phengite, garnet-biotite, chlorite, fuchsite and marble, whereas the Mercara suture contains mylonitic quartzo-feldspathic gneiss, garnet-kyanite-sillimanite gneiss, calc-silicate granulite and metagabbro. Metamorphic pressure-temperature estimations (Kumta suture: 11-18 kbar at 790-550oC; Mercara suture: 13 kbar at 825oC) suggest that, the sediments have undergone subduction to greater depths. The K-Ar age of biotite, phengite and U-Pb dating of zircon yields consistent metamorphic age of 1100-1400 Ma. In situ zircon 176Lu/177Hf isotope analysis shows wide range of εHf (t) values indicating the protolith sediments were derived from Paleo-Neoarchean juvenile crust that mixed with recycled older crust. The Bondla ultramafic-gabbro complex, northwest of the Kumta suture contains basalt, dolerite, gabbro, serpentinite, chromitite, peridotite and chromian spinel chemistry suggests evolution in a supra-subduction zone arc tectonic setting.The Sirsi shelf towards east of the Kumta suture, contains weakly deformed sedimentary rocks (limestone, shale, banded iron formations, greywacke, sandstone and quartzite) unconformable on relatively high-grade ca. 2571 Ma gneisses of the Dharwar craton. The Karwar block to the west is composed of weakly metamorphosedca. 3200 Ma tonalite-trondhjemite-granodiorite (TTG) with enclaves of amphibolite. In situ zircon 176Lu/177Hf isotope analysis and whole-rock 143Nd/144Nd isotopic analysis of TTGs show positive εHf and εNd values indicating ca. 3200 Ma juvenile crust. The Coorg block consists of ca. 3200 Ma charnockite, mafic granulites, hornblende-biotite gneiss, garnet-hornblende gabbro and anorthosite.In situ zircon 176Lu/177Hf isotope analysis indicates source as mixture of juvenile crust and older recycled crustal materials. Synthesis of the above results with published data suggests that Kumta and Mercara suture zones incorporate Paleoarchean to Mesoproterozoic sedimentssubjected to high-pressure metamorphism in the late Mesoproterozoic. Metamorphic P-T estimations of mafic granulite and U-Pb zircon geochronology of pelitic gneisses from Betsimisaraka suture zone, Madagascar suggests the rocks were underwent metamorphism at c. 24 kbar and c. 780°C during Mesoproterozoic suturing of Antongil-Masora blocks with the Antananarivo block.From the integration of above results with the new geophysical results and published data Mesoproterozoic Kumta-Mercara suture is interpreted as eastern extension of the Mesoproterozoic Betsimisaraka suture of Madagascar into western India.

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Ishwar, Kumar C. "Mesoproterozoic Suturing Of Archean Crustal Blocks In Western Peninsular India : New Insights On India-Madagascar Correlations." Thesis, 2015. http://hdl.handle.net/2005/2651.

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The structural lineament mapping of southern India along withgeological, geochronological datasets help in redefining the Precambrian crustal blocks.The newly proposed Kumta and Mercara suture zones welding Archean crustal blocks in western peninsular India offer critical insights into the crustal evolution of Gondwana. The Kumta suturemainly consists of schistose rocks including quartz-phengite, garnet-biotite, chlorite, fuchsite and marble, whereas the Mercara suture contains mylonitic quartzo-feldspathic gneiss, garnet-kyanite-sillimanite gneiss, calc-silicate granulite and metagabbro. Metamorphic pressure-temperature estimations (Kumta suture: 11-18 kbar at 790-550oC; Mercara suture: 13 kbar at 825oC) suggest that, the sediments have undergone subduction to greater depths. The K-Ar age of biotite, phengite and U-Pb dating of zircon yields consistent metamorphic age of 1100-1400 Ma. In situ zircon 176Lu/177Hf isotope analysis shows wide range of εHf (t) values indicating the protolith sediments were derived from Paleo-Neoarchean juvenile crust that mixed with recycled older crust. The Bondla ultramafic-gabbro complex, northwest of the Kumta suture contains basalt, dolerite, gabbro, serpentinite, chromitite, peridotite and chromian spinel chemistry suggests evolution in a supra-subduction zone arc tectonic setting.The Sirsi shelf towards east of the Kumta suture, contains weakly deformed sedimentary rocks (limestone, shale, banded iron formations, greywacke, sandstone and quartzite) unconformable on relatively high-grade ca. 2571 Ma gneisses of the Dharwar craton. The Karwar block to the west is composed of weakly metamorphosedca. 3200 Ma tonalite-trondhjemite-granodiorite (TTG) with enclaves of amphibolite. In situ zircon 176Lu/177Hf isotope analysis and whole-rock 143Nd/144Nd isotopic analysis of TTGs show positive εHf and εNd values indicating ca. 3200 Ma juvenile crust. The Coorg block consists of ca. 3200 Ma charnockite, mafic granulites, hornblende-biotite gneiss, garnet-hornblende gabbro and anorthosite.In situ zircon 176Lu/177Hf isotope analysis indicates source as mixture of juvenile crust and older recycled crustal materials. Synthesis of the above results with published data suggests that Kumta and Mercara suture zones incorporate Paleoarchean to Mesoproterozoic sedimentssubjected to high-pressure metamorphism in the late Mesoproterozoic. Metamorphic P-T estimations of mafic granulite and U-Pb zircon geochronology of pelitic gneisses from Betsimisaraka suture zone, Madagascar suggests the rocks were underwent metamorphism at c. 24 kbar and c. 780°C during Mesoproterozoic suturing of Antongil-Masora blocks with the Antananarivo block.From the integration of above results with the new geophysical results and published data Mesoproterozoic Kumta-Mercara suture is interpreted as eastern extension of the Mesoproterozoic Betsimisaraka suture of Madagascar into western India.

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Saygin, Erdinc. "Seismic Receiver and Noise Correlation Based Studies in Australia." Phd thesis, 2007. http://hdl.handle.net/1885/49353.

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This thesis is directed at exploiting information in the coda of seismic phases and the ambient noise field to provide new constraints on the structure of the Australian Continent. ¶ The exploitation of the immediate coda following the onset of P waves from a distant earthquake using radial receiver functions is now a well established method. The 40 sec interval following P contains reverberations and conversions, by deconvolving the radial component trace with the vertical components, the conversions are emphasized by canceling the part of the response that are common to both components. A member of different styles of such deconvolution, are investigated and a variant of the multitaper method is adopted for subsequent applications. ... ¶ The second part of the thesis is directed at the exploitation of ambient noise or seismic coda to gain information on the Green's function between seismic stations. ¶ ...

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"Effects of ion correlations in high density plasmas: Neutrino scattering and transport properties in supernovae and neutron star crusts." INDIANA UNIVERSITY, 2009. http://pqdtopen.proquest.com/#viewpdf?dispub=3337248.

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Books on the topic "Crustal Correlation"

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E, John Barbara, and Geological Survey (U.S.), eds. Crustal extension and the peak Colorado River gravity high, southern Sacramento Mountains, California: A preliminary correlation. [Reston, Va.]: Dept. of the Interior, U.S. Geological Survey, 1994.

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E, John Barbara, and Geological Survey (U.S.), eds. Crustal extension and the peak Colorado River gravity high, southern Sacramento Mountains, California: A preliminary correlation. [Reston, Va.]: Dept. of the Interior, U.S. Geological Survey, 1994.

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Book chapters on the topic "Crustal Correlation"

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Sherman, Ian. "Holocene Sea-Level Changes and Crustal Movements in the North Sea Region: An Experiment with Regional Eustasy." In Late Quaternary Sea-Level Correlation and Applications, 1–25. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0873-4_1.

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Dey, Bidisha, Kaushik Das, Nilanjan Dasgupta, Sankar Bose, Hiroshi Hidaka, and Hindol Ghatak. "Zircon U–Pb (SHRIMP) Ages of the Jahazpur Granite and Mangalwar Gneiss from the Deoli-Jahazpur Sector, Rajasthan, NW India: A Preliminary Reappraisal of Stratigraphic Correlation and Implications to Crustal Growth." In Society of Earth Scientists Series, 39–56. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-89698-4_3.

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Marquis, Guy, and Roy D. Hyndman. "Velocity-resistivity correlations in the deep crust." In Continental Lithosphere: Deep Seismic Reflections, 329–33. Washington, D. C.: American Geophysical Union, 1991. http://dx.doi.org/10.1029/gd022p0329.

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Dambara, Takeshi. "Correlation of Vertical Movement and Gravity Anomalies in Two Zones of the Japanese Islands." In The Crust and Upper Mantle of the Pacific Area, 307–11. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm012p0307.

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Litak, R. K., R. H. Marchant, L. D. Brown, O. A. Pfiffner, and E. C. Hauser. "Correlating crustal reflections with geologic outcrops: Seismic modeling results from the southwestern USA and the Swiss Alps." In Continental Lithosphere: Deep Seismic Reflections, 299–305. Washington, D. C.: American Geophysical Union, 1991. http://dx.doi.org/10.1029/gd022p0299.

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Gower, Charles F. "Correlations between the Grenville Province and Sveconorwegian Orogenic Belt — Implications for Proterozoic Evolution of the Southern Margins of the Canadian and Baltic Shields." In The Deep Proterozoic Crust in the North Atlantic Provinces, 247–57. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5450-2_15.

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Vuori, S., and A. Luttinen. "Geochemical correlations between Jurassic gabbros and basaltic rocks in Vestfjella, Dronning Maud Land, Antarctica." In Dyke Swarms - Time Markers of Crustal Evolution, 201–12. Taylor & Francis, 2006. http://dx.doi.org/10.1201/noe0415398992.ch14.

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Rao, D. Rameshwar. "Geochemical and Mineralogical Studies of Gneiss-Charnockite Rocks of Schirmacher Region, East Antarctica." In Geoscientific Investigations From the Indian Antarctic Program, 32–67. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-4078-0.ch002.

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The studies of multifaceted problems of gneiss-charnockite rocks in the Schirmacher region of East Antarctica suggest a retrograde clockwise isobaric cooling P-T history of the terrain involving an early granulite phase, a late granulite phase, and a retrograde amphibolite phase metamorphism in the region. Also, a good correlation between fluid and mineral data is observed. The high-density CO2 fluids fall well within the P-T box estimated by mineral thermobarometers, envisaging a pervasive influx of deep-seated CO2 rich fluid from the mantle resulting in the formation of the granulites, followed by decrease CO2 density fluids along with progressive influx of hydrous fluids leading to the generation of retrograde amphibolite facies rocks. The geochemical studies helped trace two-phase evolution of the region (basic magmatism around ~1200 Ma) involving a depleted mantle source implying an accretion of the juvenile crust during the late Mesoproterozoic period and major felsic magmatism around ~880 Ma involving partial melting of mafic-intermediate crust.

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Mewa, Getnet, and Filagot Mengistu. "Assessment of Landslide Risk in Ethiopia: Distributions, Causes, and Impacts." In Landslides [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.101023.

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The complex geological and geomorphological settings of Ethiopia, consisted of highland plateaus, escarpments, deeply dissected valleys, and flat lowlands, are results of multiple episodes of orogenesis, peneplanation, crustal up-doming, faulting, and emplacement of huge volumes of lava. The broad elevation contrast raging from about −125 m to 4550 m Above Mean Sea Level (AMSL) is an important factor in determining the climate regimes, vegetation types, and even populations’ lifestyles. In Ethiopia landslides, mostly manifested as rockfall, earth slide, debris, and mudflow, are among the major geohazard problems that immensely affects life, infrastructures, and the natural environment. They widely occur in the central, S-SW, and N-NW highland regions. This study discusses the distributions, causes, and impacts of landslides and presents a susceptibility zoning map produced applying the weighted overlay analysis method in the ArcGIS environment. For this purpose, key parameters (lithology, elevation, rainfall, slope angel, land use-land cover, and aspect) were selected and assigned weights by considering their contributions to slope failures. Correlations with inventory data have shown very good matching, where more than 90% of the observed data fall in areas categorized either as moderate, high, or very high susceptible zones, where appropriate risk assessments could be mandatory before approval of major projects.

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Kangarli, Talat, Tahir Mammadli, Fuad Aliyev, Rafig Safarov, and Sabina Kazimova. "Revelation of Potentially Seismic Dangerous Tectonic Structures in a View of Modern Geodynamics of the Eastern Caucasus (Azerbaijan)." In Earth's Crust and its Evolution - From Pangea to the Present Continents [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101274.

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The stress state of the earth’s crust in the Eastern Caucasus, located in the zone of collision junction of the North Caucasian, South Caucasian, and Central Iranian continental massifs, is a consequence of the inclusion of the Arabian indenter into the buffer structures of the southern framing of Eurasia at the continental stage of alpine tectogenesis. This evidenced from the results of geophysical observations of the structure and seismic-geodynamic activity of the region’s crust. The latter, at the neotectonic stage, was presented as underthrust of the South Caucasian microplate under the southern structures of Eurasia. The analysis and correlation of historical and recent seismic events indicate the confinement of most earthquake foci to the nodes of intersection of active faults with various orientations or to the planes of deep tectonic ruptures and lateral displacements along unstable contacts of material complexes of various competencies. The focal mechanisms of seismic events reveal various rupture types, but in general, the earthquake foci are confined to the nodes of intersection of faults of the general Caucasian and anti-Caucasian directions. Based on the observed weak seismicity, active areas of deep faults were identified, which are accepted as potential source zones.

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Conference papers on the topic "Crustal Correlation"

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Kowalczyk, Kamil, and Joanna Kuczynska-Siehien. "Testing Correlation between Vertical Crustal Movements and Geoid Uplift for North Eastern Polish Border Areas." In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.206.

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Long time span of observations from GNSS permanent stations can be used in the development of models of vertical crustal movements. The absolute vertical crustal movement related to the ellipsoid consists of the observed movement with relation to the mean sea level, the eustatic movement and the geoid uplift. The geoid uplift can be determined from GRACE satellite mission observations. The calculated parameters can be compared with the theoretical ones. The aim of this study is to check the correlation between vertical crustal movements and a geoid height variations determined from satellite data. GNSS data, levelling data and satellite observations for north eastern Polish border areas were used as a case study. Temporal variations of geoid were calculated based on the geopotential models from GRACE satellite observations. The obtained results give an overview of a possibility of the proposed method usage.

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Ruliansatri, V. "Present-Day 3D Lithospheric-Scale Thermal Characterization of Sumatra, Indonesia, and Its Correlation to The Regional Tectonic." In Indonesian Petroleum Association - 46th Annual Convention & Exhibition 2022. Indonesian Petroleum Association, 2022. http://dx.doi.org/10.29118/ipa22-g-79.

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We present a present-day 3D lithospheric-scale thermal model covering the Sumatra area. The structural model was built based on published geological and geophysical data which resolves major sedimentary, crustal, and lithospheric mantle packages. This process allowed us to contrast the characteristics of four hydrocarbon-prone back-arc basins namely the North Sumatra Basin (NSB), Central Sumatra Basin (CSB), South Sumatra Basin (SSB), and Sunda Basin (SB) respectively. We moreover assessed variables that influence the present-day subsurface temperature and how it relates to the area tectonic setting. The modeling process began with the creation of a 3D geological model and setting up the upper and lower boundary condition. The temperature modeling was performed by constructing a forward model that consists of multiple 1-D temperatures using Basin 3D Temperature (B3T) simulation tools, which subsequently was used to build a 3D forward model. The model was iteratively calibrated by adjusting the boundary conditions and its prior thermal properties. An ensemble smoother with multiple data assimilation (ES-MDA) method was also applied to minimize the difference between model predictions and observations. A total of 147 temperature data sets from an open access Southeast Asia research group were used to assess model accuracy. The modeled temperature distribution varies in response to the imposed heterogeneous distribution of thermal properties assigned to the different units. First-order variations in the present-day thermal structure are primarily caused by the variability in the radiogenic heat produced within the different crustal compartments, variation in the lithospheric and upper crust thickness, and the thermal blanketing effect from the sedimentary layer. This study demonstrates how first-order variations in the structurally controlled distribution of thermal properties influence the regional thermal field. Both academia and industry also can use this model as the starting point for refinement of local models of a higher spatial resolution if denser data coverage is available.

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Wen*, Baihong, Hui Yang, Qiang Wei, and Lianqun Zhang. "Gravity Fields and their Correlation Analysis of Crustal Density Structure of Cratonic Basins in China." In GEM 2019 Xi'an: International Workshop and Gravity, Electrical & Magnetic Methods and their Applications, Chenghu, China, 19-22 April 2015. Society of Exploration Geophysicists and Chinese Geophysical Society, 2019. http://dx.doi.org/10.1190/gem2019-043.1.

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Bala, Andrei. "CRUSTAL STRUCTURE MODELS IN WESTERN PART OF ROMANIA USING CROSS CORRELATION OF SEISMIC NOISE AND RECEIVER FUNCTIONS." In 16th International Multidisciplinary Scientific GeoConference SGEM2016. Stef92 Technology, 2016. http://dx.doi.org/10.5593/sgem2016/b13/s05.056.

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Issawy, E., J. Mrlina, and A. Radwan. "Vertical Crustal Movements as Deduced from Temporal Gravity Variations and Its Correlation to Seismic Hazards in Egypt." In 75th EAGE Conference and Exhibition incorporating SPE EUROPEC 2013. Netherlands: EAGE Publications BV, 2013. http://dx.doi.org/10.3997/2214-4609.20130712.

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Kowalczyk, Kamil. "Testing the Correlation Between the Vertical Crustal Movements and Temperature Changes on the Example of Selected Vectors Permanent GNSS Stations." In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.205.

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In the last years air temperature increasing gradual. It also changes depending on the area: metropolitan, rural. The temperature changes directly affects the expansion of materials of which are made geodetic control network and support infrastructure. This may be influenced on the daily change in the amount determined for permanent GNSS stations. The main aim of the article is to examine the relationship between height changes and temperature changes. Daily difference in height between the selected stations Polish ASG EUPOS and the temperature in the vicinity of the stabilization of these stations data were used. Three year period was taken to the analysis. The results give a view on the article thesis.

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Dimitrov, Nikolay, and Mila Atanasova. "GEODETIC DATABASE FOR MONITORING OF GEODYNAMIC PROCESSES IN THE REGION OF SOFIA AND SOUTHWESTERN BULGARIA." In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/2.1/s09.28.

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This paper covers the activities of creating a database for the study of modern crustal movements in the region of Sofia and Southwestern Bulgaria, including data from GNSS measurements of the geodynamic network and the results of their processing and analysis, data from permanent stations and archive data from Synthetic-aperture radar, processing and obtaining interferometric images. The local archive of GNSS measurement includes: manual sketches of the location of the points; log sheets of the measurement with information for the height of the antenna, start and end time of measurement and operator name; raw GNSS measurements and data in RINEX format. Data from permanent stations are extracted from external repositories such as IGS or SOPAC are also included in the archive. The local archive of interferometric images contains scenes from the Sentinel-1 satellite downloaded from the repository of the European Space Agency's Science Center. Data for a digital terrain model are extracted from external sources, such as SRTM or ASTER repositories are also included. In order of the envisaged integration with GNSS data, it should be borne in mind that both types of data must be in the same reference system. Measurement campaigns in the geodetic network are carried out in a certain period of time and these periods are used as reference, which allows comparisons to the information extracted from interferometric images. The available experience shows that there is a good correlation between the two types of data. The processing and analysis of the obtained results is another important part of the local archive. The database thus created contains important information and allows for a more accurate analysis of ongoing geodynamic processes in the study area and obtaining reliable information for better regional planning from local authorities.

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Doneva, Blagica. "CORRELATION BETWEEN THE EARTHS CRUST STRUCTURE AND SEISMICITY." In SGEM2011 11th International Multidisciplinary Scientific GeoConference and EXPO. Stef92 Technology, 2011. http://dx.doi.org/10.5593/sgem2011/s06.105.

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Caballero, O. L., C. J. Horowitz, Ricardo Alarcon, Philip L. Cole, Chaden Djalali, and Fernando Umeres. "Effects of Ion Correlations in Supernovae and Neutron Star Crusts." In VII Latin American Symposium on Nuclear Physics and Applications. AIP, 2007. http://dx.doi.org/10.1063/1.2813836.

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Gaus-Liu, Xiaoyang, Alexei Miassoedov, and Stephan Gabriel. "Review of Experimental Studies on the Heat Transfer Behaviour of Volumetrically-Heated Pool With Different Boundary Conditions and the Influence of Crust Formation." In 2016 24th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icone24-60268.

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This study investigates the heat transfer characters of a volumetrically-heated melt pool in LWR lower plenum under different top and side boundary conditions. The inconsistency in parameter definitions in Nu-Ra correlations is addressed, and the effect of 2D geometry and crust formation are analyzed. A summary of test conditions of the previous experimental studies are given. The average upwards and downward Nusselt number from LIVE tests in 3D and 2D geometries are compared with each other and with other well-known correlations. The differences of heat flux distribution along the vessel wall are analyzed regarding boundary cooling condition and crust formation. This paper provides some explanations about the discrepant among the exiting heat transfer correlations and recommends most suitable descriptions of melt pool heat transfer under different accident management scenarios.

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Reports on the topic "Crustal Correlation"

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Harris, L. B., P. Adiban, and E. Gloaguen. The role of enigmatic deep crustal and upper mantle structures on Au and magmatic Ni-Cu-PGE-Cr mineralization in the Superior Province. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328984.

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Aeromagnetic and ground gravity data for the Canadian Superior Province, filtered to extract long wavelength components and converted to pseudo-gravity, highlight deep, N-S trending regional-scale, rectilinear faults and margins to discrete, competent mafic or felsic granulite blocks (i.e. at high angles to most regional mapped structures and sub-province boundaries) with little to no surface expression that are spatially associated with lode ('orogenic') Au and Ni-Cu-PGE-Cr occurrences. Statistical and machine learning analysis of the Red Lake-Stormy Lake region in the W Superior Province confirms visual inspection for a greater correlation between Au deposits and these deep N-S structures than with mapped surface to upper crustal, generally E-W trending, faults and shear zones. Porphyry Au, Ni, Mo and U-Th showings are also located above these deep transverse faults. Several well defined concentric circular to elliptical structures identified in the Oxford Stull and Island Lake domains along the S boundary of the N Superior proto-craton, intersected by N- to NNW striking extensional fractures and/or faults that transect the W Superior Province, again with little to no direct surface or upper crustal expression, are spatially associated with magmatic Ni-Cu-PGE-Cr and related mineralization and Au occurrences. The McFaulds Lake greenstone belt, aka. 'Ring of Fire', constitutes only a small, crescent-shaped belt within one of these concentric features above which 2736-2733 Ma mafic-ultramafic intrusions bodies were intruded. The Big Trout Lake igneous complex that hosts Cr-Pt-Pd-Rh mineralization west of the Ring of Fire lies within a smaller concentrically ringed feature at depth and, near the Ontario-Manitoba border, the Lingman Lake Au deposit, numerous Au occurrences and minor Ni showings, are similarly located on concentric structures. Preliminary magnetotelluric (MT) interpretations suggest that these concentric structures appear to also have an expression in the subcontinental lithospheric mantle (SCLM) and that lithospheric mantle resistivity features trend N-S as well as E-W. With diameters between ca. 90 km to 185 km, elliptical structures are similar in size and internal geometry to coronae on Venus which geomorphological, radar, and gravity interpretations suggest formed above mantle upwellings. Emplacement of mafic-ultramafic bodies hosting Ni-Cr-PGE mineralization along these ringlike structures at their intersection with coeval deep transverse, ca. N-S faults (viz. phi structures), along with their location along the margin to the N Superior proto-craton, are consistent with secondary mantle upwellings portrayed in numerical models of a mantle plume beneath a craton with a deep lithospheric keel within a regional N-S compressional regime. Early, regional ca. N-S faults in the W Superior were reactivated as dilatational antithetic (secondary Riedel/R') sinistral shears during dextral transpression and as extensional fractures and/or normal faults during N-S shortening. The Kapuskasing structural zone or uplift likely represents Proterozoic reactivation of a similar deep transverse structure. Preservation of discrete faults in the deep crust beneath zones of distributed Neoarchean dextral transcurrent to transpressional shear zones in the present-day upper crust suggests a 'millefeuille' lithospheric strength profile, with competent SCLM, mid- to deep, and upper crustal layers. Mechanically strong deep crustal felsic and mafic granulite layers are attributed to dehydration and melt extraction. Intra-crustal decoupling along a ductile décollement in the W Superior led to the preservation of early-formed deep structures that acted as conduits for magma transport into the overlying crust and focussed hydrothermal fluid flow during regional deformation. Increase in the thickness of semi-brittle layers in the lower crust during regional metamorphism would result in an increase in fracturing and faulting in the lower crust, facilitating hydrothermal and carbonic fluid flow in pathways linking SCLM to the upper crust, a factor explaining the late timing for most orogenic Au. Results provide an important new dataset for regional prospectively mapping, especially with machine learning, and exploration targeting for Au and Ni-Cr-Cu-PGE mineralization. Results also furnish evidence for parautochthonous development of the S Superior Province during plume-related rifting and cannot be explained by conventional subduction and arc-accretion models.

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Agassi, Menahem, Michael J. Singer, Eyal Ben-Dor, Naftaly Goldshleger, Donald Rundquist, Dan Blumberg, and Yoram Benyamini. Developing Remote Sensing Based-Techniques for the Evaluation of Soil Infiltration Rate and Surface Roughness. United States Department of Agriculture, November 2001. http://dx.doi.org/10.32747/2001.7586479.bard.

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The objective of this one-year project was to show whether a significant correlation can be established between the decreasing infiltration rate of the soil, during simulated rainstorm, and a following increase in the reflectance of the crusting soil. The project was supposed to be conducted under laboratory conditions, using at least three types of soils from each country. The general goal of this work was to develop a method for measuring the soil infiltration rate in-situ, solely from the reflectance readings, using a spectrometer. Loss of rain and irrigation water from cultivated fields is a matter of great concern, especially in arid, semi-arid regions, e.g. much of Israel and vast area in US, where water is a limiting factor for crop production. A major reason for runoff of rain and overhead irrigation water is the structural crust that is generated over a bare soils surface during rainfall or overhead irrigation events and reduces its infiltration rate (IR), considerably. IR data is essential for predicting the amount of percolating rainwater and runoff. Available information on in situ infiltration rate and crust strength is necessary for the farmers to consider: when it is necessary to cultivate for breaking the soil crust, crust strength and seedlings emergence, precision farming, etc. To date, soil IR is measured in the laboratory and in small-scale field plots, using rainfall simulators. This method is tedious and consumes considerable resources. Therefore, an available, non-destructive-in situ methods for soil IR and soil crusting levels evaluations, are essential for the verification of infiltration and runoff models and the evaluation of the amount of available water in the soil. In this research, soil samples from the US and Israel were subjected to simulated rainstorms of increasing levels of cumulative energies, during which IR (crusting levels) were measured. The soils from the US were studied simultaneously in the US and in Israel in order to compare the effect of the methodology on the results. The soil surface reflectance was remotely measured, using laboratory and portable spectrometers in the VIS-NIR and SWIR spectral region (0.4-2.5mm). A correlation coefficient spectra in which the wavelength, consisting of the higher correlation, was selected to hold the highest linear correlation between the spectroscopy and the infiltration rate. There does not appear to be a single wavelength that will be best for all soils. The results with the six soils in both countries indeed showed that there is a significant correlation between the infiltration rate of crusted soils and their reflectance values. Regarding the wavelength with the highest correlation for each soil, it is likely that either a combined analysis with more then one wavelength or several "best" wavelengths will be found that will provide useful data on soil surface condition and infiltration rate. The product of this work will serve as a model for predicting infiltration rate and crusting levels solely from the reflectance readings. Developing the aforementioned methodologies will allow increased utilization of rain and irrigation water, reduced runoff, floods and soil erosion hazards, reduced seedlings emergence problems and increased plants stand and yields.

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