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2.
Combined subsidence and thermal 1D modelling was performed on six well-sections located in the north-western Mid-Polish Trough/Swell
in the eastern part of the Central European Basin system. The modelling allowed constraining quantitatively both the Mesozoic
subsidence and the magnitude of the Late Cretaceous–Paleocene inversion and erosion. The latter most probably reached 2,400 m
in the Mid-Polish Swell area. The modelled Upper Cretaceous thickness did not exceed 500 m, and probably corresponded to 200–300 m
in the swell area as compared with more than 2,000 m in the adjacent non-inverted part of the basin. Such Upper Cretaceous
thickness pattern implies early onset of inversion processes, probably in the Late Turonian or Coniacian. Our modelling, coupled
with previous results of stratigraphic and seismic studies, demonstrates that the relatively low sedimentation rates in the
inverted part of the basin during the Late Cretaceous were the net result of several discrete pulses of non-deposition and/or
erosion that were progressively more pronounced towards the trough axis. The last phase of inversion started in the Late Maastrichtian
and was responsible for the total amount of erosion, which removed also the reduced Upper Cretaceous deposits. According to
our modelling results, a Late Cretaceous heat-flow regime which is similar to the present-day conditions (about 50 mW/m2) was responsible for the observed organic maturity of the Permian-Mesozoic rocks. This conclusion does not affect the possibility
of Late Carboniferous–Permian and Late Permian–Early Triassic thermal events. 相似文献
3.
David J. A. Williams Beda A. Hofmann Ian G. Glasspool 《Swiss Journal of Geoscience》2008,101(3):651-658
Vitrinite reflectance (Rr), proximate analysis and carbon isotope composition (δ13C) have been used to characterise coal samples from two zones of Late Carboniferous sediments (Gastern and Ferden) in the Aar massif where they are penetrated by the Lötschberg base tunnel (constructed between 1999 and 2005). Samples are characterised by variable ash yields (21.7–93.9%; dry basis); those with ash yields of less than ~50% and with volatile matter content (V;dry ash-free basis) within the limits 2 < V% ≤ 8 are anthracite. Values of Rr range from 3.89% to 5.17% and indicate coalification to the rank of anthracite and meta-anthracite in both Gastern and Ferden Carboniferous zones. Samples of anthracite and shale from the Gastern Carboniferous exhibit a relatively small range in δ13C values (–24.52‰ to –23.38‰; mean: –23.86‰) and are lighter than anthracite samples from the Ferden Carboniferous (mean: –22.20‰). The degree of coalification in the Gastern and Ferden Carboniferous zones primarily depends on the maximum rock temperature (T) attained as a result of burial heating. Vitrinite reflectance based estimates of T range from ~290° –360 °C. For a proposed palaeogeothemal gradient of 25 ° C/km at the time of maximum coalification the required overburden is attributable to relatively thin autochtonous Mesozoic/Cenozoic sedimentary cover of the Aar massif and Gastern granite and deep tectonic burial beneath advancing Helvetic, Ultrahelvetic and Prealpine (Penninic) nappes in Early Oligocene to Miocene. 相似文献
4.
SUN Xiao-jie LI Chao-lin WANG Li-bin REN Ri-chun LI Hai-yan ZHUANG Yi-ming LIU Ying-xin SUN Ke .Daqing Petroleum Institute Daqing Heilongjiang China .Coalfield Geological Geophysical Exploration Company of Jilin Province Changchun China .Coal Field Geology Bureun of Jilin Province Changchun China 《吉林大学学报(地球科学版)》2006,(Z2)
已知勘查区深度范围前提下,最大炮检X和道间距ΔX,不可以太大也不可以太小,施工前能够计算出它的允许值范围。 相似文献
5.
用空间分辨率为1km的MODIS和MISR数据可计算16天BRDF和反照率产品,该文证明了在多数采样条件下,用MODIS/MISR角度采样的BRDF和反照率反演精度在5到10个百分点以内。 相似文献
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Saturated and aromatic biomarker ratios continue to change systematically through the oil window and into the gas-condensate window to high vitrinite reflectances (Ro = 1.16%) in mature marine and lacustrine Mesozoic clastic samples from a South African basin. Two of the ratios reverse above Ro = 0.9%. These unusual maturation effects result from isolated periods of high rates of maturation increase. The basin cooled regionally after the break-up of Gondwana but high heating rates prevailed during the late Cretaceous-early Tertiary, as Africa moved across a hotspot, and again in the late Tertiary as a result of a possible hotspot and hydrothermal event. 相似文献
8.
植被冠层多角度遥感研究进展 总被引:7,自引:0,他引:7
综述了近年来关于植被冠层多角度遥感研究的最新成果,分别讨论了二向性反射的正向模型和参量反演问题在理论和实际应用中的新进展。分析了卫星平台多角度遥感的应用前景及面临的困难,指出了未来多角度遥感研究的新方向。 相似文献
9.
VICARIOUS RADIOMETRIC CALIBRATION OF SATELLITE FY-ID SENSORS AT VISIBLE AND NEAR INFRARED CHANNELS
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ZHANG Yuxiang QIU Kangmu HU Xiuqing RONG Zhiguo ZHANG Lijun 《Acta Meteorologica Sinica》2004,18(4):505-516
For the problem of in-flight test site radiometric calibration for the FY-1D Meteorological Satellite onboard sensor's visible and near infrared channels,this paper described the calibration method,satellite-ground synchronous observation data acquired at China Dunhuang Calibration Test Site,parameter derivation and radiative transfer computation during the calibration,and the calibration result analysis.At FY-1D seven channels (with central wavelength at Channels 1:630 nm,2:865 nm;6:1610 nm;7:455 nm,8:505 nm;9:555 nm;10:932 nm),calibration coefficients obtained during the ground site calibration were compared with that respectively of prelaunch calibration.It is demonstrated that results of FY-1D onboard two sensors' (A and B) at channels 1,2,6 and 10 were close to pre-calibration,and the absolute difference of Gobi desert reflectance computed using test site and pre-launch calibration coefficients was no more than 2%. At other channels,large pre-launch calibration errors resulted in a poor consistency between the test site and pre-launch calibration.The errors can be corrected by the test site calibration results. Based on a rough estimation,the overall error of the calibration was about 6%. The paper also presented the in-flight vicarious calibration at the visible and near infrared channels of FY-1C sensor A which was launched in 1999 and has been put into operational mode since 2002.The results exhibit that FY-1C sensor's response has 23% attenuation at Channels 7 and 8,while only minor degradation at the other channels was found. During the mission,calibrations were also conducted at NOAA-17's Channels 1 and 2 (1:430-830 nm,2:500-1072 nm).A very good consistency has been achieved between the test site and pre-launched calibration results. 相似文献
10.
1IntroductionThecarbonisotopiccompositionofnaturalgasesisregardedasacontanttracerusedinthegeochemicalresearchofnaturalgases .Basedonthecarbonisotopiccomposition ,thegenetictypesofnaturalgasesarebasicallydividedtodeterminethematurationofnaturalgasesandmakegas sourcecorrelations (Stahl,1 973;StahlandCarey ,1 975;Stahletal.,1 977;James ,1 983;Schoell,1 983,1 988;DaiJinxingetal.,1 992 ;FuJiamoetal.,1 992 ;XuYongchang ,1 994 ) .Theformationofnaturalgasescouldbededucedintermsofcarbonisotopicvar… 相似文献