Investigation of the wide-range maturity indices for sedimentary organic matter

1.用甲基二苯并噻吩表征日本泥岩中甲基菲的宽范围成熟度指标：用甲基二苯并噻吩表征日本泥岩中甲基菲指数（PFI），一种宽范围成熟度指标。通过对新泻县中新统七谷寺泊组（MITI Tomikura and Tojo）、秋田县女川组（Onnagawa Formation）、岛根县定宗寺组（Josoji Formation）和高知县下第三纪四万多群（Shimanto Group）泥岩的MPI值变化及其与Ro %的关系进行研究，发现了4个泥岩的MPI值。对于所有岩石样本，MPI显示在成熟区（%Ro=0.5-1.9）中从0.7增加到4.2，在过成熟区（%Ro=1.9-4.5）中从4.2减少到1.3。用地球化学动力学方法讨论了这些趋势的上斜率，认为MPI的变化取决于中间MPI的产生和α-异构体向β-异构体的甲基转移 关于我们 甲基菲的变化：为了了解油窗内MPI的变化，通过对女川组猿川原油与粘土矿物（膨润土）和水在300、350、370、380、400和450℃的热/压稳定反应器中的加热实验，研究了MPI变化的地球化学动力学。通过加热实验获得了上斜率内MPI变化的活化能（E）和频率因子（A）如下：E = 57.2 kcal/mol和A = 2.23 x 10^<12>s^<-1>。3.日本西南部岛根半岛中新世定宗寺黑色泥岩的接触变质作用：研究了岛根半岛中新世定宗寺黑色泥岩在接触变质作用下有机质组成的变化。选择了三个有代表性的露头，其中黑色泥岩被云英岩和安山岩熔岩侵入。从接触面至约30 m距离处采集了若干岩石样品。相对于安山岩，热对流对泥岩的影响更大。这是由于入侵的规模。4.日本西南部中新统Josoji组黑色泥岩中有机质的成分变化：本研究是沉积岩中有机质分解的初步实验工作。本文研究了半岛岛根中新统寺组暗色泥岩加热后有机质组成的变化。泥岩在恒温炉中加热。I. e. 200、250、300、350、400、450、500、550和600℃，持续2天。600 ℃实验后，岩石的TOC（总有机碳）、TN（总氮）和TS（总硫）分别下降到原始岩石的50%、25%和20%。降植烷/植烷比率和碳偏好指数分别从4.3降至0.3和从1.1降至0.25。HI（氢指数）从43异常降低至1。少

1.Characterization of Methylphenanthrene with Methyldibenzothiophen as wide-range maturity indicator in mudrocks, Japan :Methylphenanthrene index (PFI), a wide-range maturation indicater, was characterized with methyldebenzothiophen for the Cretaceous-tertialy mudstones in Japan. Mudstones from Miocene Nanatani-Teradomari Formation (MITI Tomikura and Tojo) in Niigata Prefecture, Onnagawa Formation in Akita prefecture, Josoji Formation in Shimane Prefecture and Cretaceous-Tertiary Shimanto Group in Kochi Prefecture were investigated to know the variation of MPI and its relation to %Ro. For all rock samples, the MPI showed increase from 0.7 to 4.2 in the mature zone (%Ro=0.5-1.9) and decrease from 4.2 to 1.3 in the over-mature zone (%Ro=1.9-4.5). The upper slope in these trends was discussed by means of geochemical kinetics, suggesting that the MPI change depend on production of intermediate MPI and the methyl-shift from α-isomer to β-isomer.2.Geochemical kinetic parameters for isomeriza … More tion of Methylphenanthrene :To know the variation of MPI in the oil window, the geochemical dynamics of MPI change were examined by the heating experiment of Sarukawa crude oil from Onnagawa Formation with clay mineral (bentonite) and water in the heat/pressure-stable reactor at 300, 350, 370, 380, 400 and 450℃. The activation energy (E) and frequency factor (A) of the MPI change within the upper slope were obtained by the heating experiment as follows : E = 57.2 kcal/mol and A = 2.23 x 10^<12> s^<-1>. Based on the results, the relationship between MPI and maximum paleo-temperature was estimated for some basin.3.Contact metamorphism of Miocene Josoji black mudstones in Shimane Peninsula, southwest Japan :Compositional changes in organic matter by contact metamorphism were investigated for Miocene Josoji black mudstones in Shimane Peninsula. Three representative outcrops were selected, where the black mudstones have invaded by ryorite and andesite lava. Several rock samples were collected from the contact plane to about 30m distance. The ryorite supposed to have thermally influenced the mudstones more than the andesite. This is due to size of the intrusion. The ryorite decomposed organic matter to be less than 10%, but the andesite to be only about 70%.4.Compositional changes in organic matter artificially heated black mudstone from Miocene Josoji formation, southwest Japan :This study is a preliminary experimental work on decomposition of organic matter in sedimentary rocks. Compositional changes in the organic matter after heating blask mudstone from Miocene Josoji formation, Shimane peninsula were investigated. The mud rocks were heated in an oven at constant temperature. i. e. 200, 250, 300, 350, 400, 450, 500, 550 and 600℃, for 2 days. After the experiment of 60O℃, TOC (total organic carbon), TN (total nitrogen) and TS (total sulfur) decreased to 50%, 25% and 20% of the initial rocks, respectively. Pristane/Phytane ratio and CPI (carbon preference index) decreased from 4.3 to 0.3 and from 1.1 to 0.25, respectively. HI (hydrogen index) abnormally decreased from 43 to 1. Less