References:

[1]    England W A, Mackenzie A S, Mnn D M, Quigley T M. The movement and entrapment of petroleum fluids in the subsurface [J]. Journal of the Geological Society, 1987, 144(2): 327-347.

在surfer 中打开NGDC上下载来的高程数据，在Data中选择 new projected coordinate，在source columns 中选择 World Geodetic System 1984 (wgs84)投影系统，在target columns 中选择目标区所用的投影参数，比如Beijing 54(北京54)。完成后保存数据，用surfer 成图(网格化时选择 Modified shepard’s method)，结果如下图。

    水在烃源岩中是普遍存在的，水对源岩的生排烃的作用不容忽视。那么水在源岩的生烃中到底起什么作用呢？Lewan（1997）的研究结果表明，水在干酪根转换成沥青的过程中（首先断开弱化学键）作用不明显，但对于沥青进一步转换成石油（断开共价键，形成自由基）却是重要的因素。在无水条件下，沥青主要发生交联作用，生成焦沥青（pyrobitumen）；而有水条件下，沥青主要发生裂解作用，生成饱和烃。Schimmelmann(1999,2001)等通过重水（D₂O）示踪研究加水热模拟实验中氘的流向进而研究水的作用机理，结果表明烃源岩加水生烃过程中，普遍存在水的氢转换成有机质中的氢。这种转换程度与源岩的渗透率及源岩颗粒大小有关；渗透率越大，颗粒越小，水与源岩的接触面积越大，这种转化程度也越高。相对其它有机质类型，Ⅰ型干酪根主要为烷基链，不易形成自由基，因此Ⅰ型有机质生成的油中含有的来自水的氢的含量最低，其余几种类型有机质生成的石油中的来自水的氢的比例依次增加：Ⅱ≈Ⅲ>ⅡS。

    启示：水中的氢在生烃过程中可以转换成有机氢，因此，对于一些贫氢的有机质的生烃作用，我们可能需要重新审视。

主要参考文献：

[1]Arndt Schimmelmann, Jean-Paul Boudou, M.D Lewan and etc. (2001) Experimental controls on D/H and 13C/12C ratios of kerogen bitumen and oil during hydrous pyrolysis.Org Geochem, 32(8):1009-1018.

[2]M.D Lewan. (1993)Laboratory simulation of petroleum formation: hydrous pyrolysis. Org Geochem, New York 1993,419-442.

[3]M.D Lewan. (1997)Experiments on the role of water in petroleum formation. Geochimica et Cosmochimica Acta, 61(17), 3691-3723.

原写于：http://blog.5d.cn/user2/skyline-moon/200907/521385.html

    冷冰冰的地图如何变得妙趣横生？Zotero的开发人员无时无刻不在寻找对资料库进行创新式的管理与可视化的方法。这样，将资料库反映出的地理信息标在地图上就进入我们的视线。下面，我们将兴奋向Zotero粉丝们宣布Zotero的新插件：地图可视化插件（Zotero maps），这个插件目前可以从这里下载。Zotero地图插件是由Entropy Free LLC 和Zotero项目组共同开发完成的。地图插件可以向用户们展示他们的资料之间的地理信息及其关系，并在地图上标出这些信息和联系。反过来，Zotero也可以用创建的地图作为资料的导航。地图插件的效果可见下图。

下面我将向大家介绍如何在Zotero中使用地图插件：

    下载安装好地图插件后，你可以在操作（Action）菜单下（齿轮状小图标）找到创建地图（Create Map）的子菜单。点击Create Map菜单，将弹出参数窗口，这些参数将指导Zotero如何来搜集资料中地理信息。点击确定后，Zotero将在浏览器中生成一张地图，并在图上标注出各个资料的地理位置。Zotero地图使用 OpenStreetMap 创建地图, 你可以通过拖动，放大、缩小操作来浏览地图。当然你也可以通过点击图上的地理标签来显示相关的资料信息。

    Zotero地图插件通过自定义的值域组合来搜集资料中的地理信息。如下图，你可以选择标题、标签、摘要、附件，甚至笔记等值域来定义文献的地理信息。更为重要的是，Zotero可以自动搜集PDFs文本中的地理信息，并将它们标注在地图上。

潜在的应用实例:
根据地理关键词，绘制资料的地理信息图:
    许多资料分类表和杂志数据库都包含有地理信息的关键词。Zotero地图可以快速查阅分类标签、作者、及出版机构之间的相互关系。你也可以自己定义这些地理标签。无论你是研究禽流感的主要分布地区，美国西南部的人种研究，抑或是美国的奴隶贸易，资料中的标签都可以提供有用的地理信息。

绘制图版地分布图:
    很多情况下，出版社的地点包含了重要的信息。比如你的研究是关于图书的历史，则不同媒体传输管道对同一事件的报道有什么不同，不同杂志之间如何表达不同的科学观点，以及这些资料是如何发表出来的都能提供重要的参考。

原文链接：http://www.zotero.org/blog/zotero-maps-visualize-your-zotero-library-on-the-globe/

1. 去掉一列中重复的记录:
   在该列(比如第一列)的右侧的第一个单元格写: =if(A2=A1,”重复”,”"),移动鼠标到该单元格的右下角,鼠标变成”黑十字”时,双击。然后用自动筛选的方法，把所有有”重复”字样的行删除。
2. =vlookup(查找的值，查找的范围，返回第几列的数，false)
   false 表示精确匹配，true为模糊匹配
   如=vlookup(g1，A:B,2,false) 表示在A，B两列中查找单元格g1中的值，返回B列中对应（同一行）的值
3. 同一样品多次记录求平均值
   分为两步：第一步先把样品号拷出来，去掉重复的样品号；第二步在没有重复的样品号旁边编写公式：＝sumif(左侧的样品号，原来样品号所在的列，要求和的记录所在的列）/countif(左侧的样品号，原来样品号所在的列)
   如：sumif(E1,A:A,B:B)/countif(E1,A:A)
4. 菜单：数据｜分列
   用于整理从文本文件拷进来的数据
5. 菜单 数据｜筛选
   可以自动或自定义筛选出符合一定条件的数据
6. Excel 公式中的绝对引用与相对引用
   如引用的单元格写成 A1 表示相对引用，这时如果把该公式拖到比如第二行，则公式中的A1会自动变成A2；而如果拖到相邻的单元格，则会自动变成B1。

   如果引用的单元格写成 $ A1则表示绝对引用A，相对引用1。这时如果把公式拖到第二行，则公式中的$ A1变成$ A2；但是如果拖到相邻的单元格，则公式中的$ A1还是$ A1，仍然引用的是A1单元格，而不是单元格B1

   如果引用的单元格写成$ A$ 1则无论公式拖到哪里，都表示引用的是A1单元格。

7. Excel常用的插件整理
8. 7.1 数据插值工具（XlXtrFun 免费），http://www.xlxtrfun.com/XlXtrFun/XlXtrFun.htm
   XlXtrFun是一个数据插值外推的宏包，可以实现一组数据的线性，Spline等方法的插值及实验数据的拟合。

1. Mackenzie,et al. Principle of geochemical prospect appraisal,AAPG Bull,1988,72(4):399-415.
2. Mackenzie,et al. A novel approach for recognition and quantification of hydrocarbon migration effects in shale-sandstone sequences. AAPG Bull,1984,68(2):196-219.
3. Harry Dembicki, JR.,et al. Source rock evaluation by pyrolysis-gas chromatography, AAPG Bull,1983,67(7):1094-1103.
4.Bishop, et al.Concepts for estimating hydrocarbon accumulation and dispersion, AAPG Bull,1983,67(3):337-348.
5.Cooles,et al. Calculation of petroleum masses generated and expelled from source rocks, Org. Geochem.,1986,10:235-245.
6.Lewan.Experiments on the role of water in petroleum formation,GCA,1997,61(17):3691-3723.
7.Katz, Limitations of ‘rock-eval’ pyrolysis for typing organic matter, Org. Geochem.,1983,4(3/4):195-199.
8.Peters, Guidelines for evaluation petroleum source rock using programmed pyrolysis, AAPG Bull,1986,70(3):318-329.
9.Landford, et al. Interpreting rock-eval pyrolysis data using graphs of pyrolizable hydrocarbons vs. total organic carbon,1990,74(6):799-804.
10.Conford, et al. Geochemical truths in large data sets. I: Geochemical screening data, Org. Geochem,1998,29(1-3):519-530.
11.Espitalie,et al. Role of mineral matrix in kerogen pyrolysis: influence on petroleum generation and migration,1980,64(1):59-66.
12.Dembicki, Three common source rock evaluation errors made by geologists during prospect or play appraisals, AAPG Bull,2009,93(3):341-356.

待续…

• 生烃动力学方面(petroleum generation kinetics)
• 生物标志物方面(biomarker)
• 同位素方面(isotope)
• 油气系统模拟方面(basin modeling)

In petroleum exploration it is important to be able to determine the origin of any gas which is found. This paper describes a new method of estimating the source-type and maturity of a gas based on a Rayleigh fractionation model. Kerogen is divided conceptually into a labile (dominantly oil-generating) fraction and a refractory, gas-prone, component. [delta]13C of methane from either kerogen type, and ethane, propane and butane for gases from labile kerogen, can be defined as a function of [delta]13C of the gas precursor groups in kerogen, a kinetic isotope fractionation factor, k, and the extent of gas generation. The isotopic ratio of the methane precursors relative to bulk kerogen, determined from laboratory pyrolysis, are -17.5[per mille sign] for labile kerogen and -1.4[per mille sign] for refractory kerogen. Values for ethane, propane and butane from labile kerogen, based on field correlations, are -4.9[per mille sign], -2.2[per mille sign] and -1.6[per mille sign] respectively. The corresponding fractionation factors are 0.9892, 0.9919, 0.9947 and 0.9975 for methane, ethane, propane and butane respectively from labile kerogen, and 0.9984 for methane from refractory kerogen. Using these parameters, summary diagrams are constructed which allow differentiation of these sources from each other and from biogenic gases and cracked oil, and recognition of gases of mixed origin. If an independent estimate of [delta]13C for the source kerogen is possible, then [delta]13C of the gas components can be used to estimate maturity in terms of the Gas Generation Index, the fraction of gas potential which has been realized.

Cramer, B., B. M. Krooss, et al. (1998). “Modelling isotope fractionation during primary cracking of natural gas: a reaction kinetic approach.” Chemical Geology 149(3-4): 235-250.

A numerical model has been developed to compute stable carbon isotope variations in natural gas (methane) by calculating and generation as a set of parallel first-order reactions of primary cracking. The goal of this work was to combine the description of isotope fractionation with established kinetic models for gas generation. Stable carbon isotope ratios of methane from sedimentary organic matter are characterized by the initial carbon isotope ratio of methane precursors within the organic matter and by a constant difference in activation energy between and generation from corresponding precursor sites. Methane generation is calculated separately for and . A difference in activation energy automatically implies a temperature dependence of fractionation processes which has not been taken into consideration in previous works. This new model offers a theoretical explanation and mathematical description of the observed variability of [delta]-values of methane during open-system pyrolysis experiments. Carbon isotopes of methane within natural gas of thermogenic origin can be simulated for any geological temperature history. The application of the method to two coaly rock samples of the Pokur formation from northern West Siberia results in simulated carbon isotope values of methane which are very similar to those in the natural gas within the reservoirs of the Pokur formation ([delta]=-42[per mille sign] to -54[per mille sign]). This finding supports a thermogenic origin of the gas at an early stage of maturation.

Lorant, F., A. Prinzhofer, et al. (1998). “Carbon isotopic and molecular constraints on the formation and the expulsion of thermogenic hydrocarbon gases.” Chemical Geology 147(3-4): 249-264.

The purpose of this paper is to present a new kinetic model for the generation of hydrocarbon gas, linking isotopic fractionation and molecular compositions. Pyrolysis experiments were performed with a Type II kerogen in a confined system under isothermal and anhydrous conditions. A mathematical formalism is applied to a compositional kinetic scheme using the pyrolysis data. The experimental and numerical simulations show that the δ13C of the hydrocarbon gas species increase and diverge in value at high maturity, and that the C2−C5 become more enriched in 13C than the initial kerogen. Such an experimental isotopic evolution is not observed in most geological cases, where the δ13C of the thermogenic gas hydrocarbons tend to converge when the maturity increases. From a comparison between experimental isotopic data from closed and open systems, we propose that the two different trends–divergence vs. convergence–may be explained by taking into account the residence time of the gas in the source, for a given generation rate. Indeed, the residence time appears to be a strongly controlling factor for the isotopic and molecular genetic signatures (δ13C and dryness) of the thermogenic hydrocarbons. This assumption is tested by comparing modeling results with experiments and natural data using a diagram showing the difference in δ13C of ethane and propane as a function of the ratio. Results show that the evolution trends observed in such a diagram obey a logic depending on both the maturity and the expulsion rate of hydrocarbons.

Tang, Y., J. K. Perry, et al. (2000). “Mathematical modeling of stable carbon isotope ratios in natural gases.” Geochimica et Cosmochimica Acta 64(15): 2673-2687.

A new approach is presented for mathematical modeling of stable carbon isotope ratios in hydrocarbon gases based on both theoretical and experimental data. The kinetic model uses a set of parallel first-order gas generation reactions in which the relative cracking rates of isotopically substituted (k*) and unsubstituted (k) bonds are represented by the equation k*/k=(Af*/Af) exp(-[Delta]Ea/RT), where R is the gas constant and T is temperature. Quantum chemistry calculations have been used to estimate the entropic (Af*/Af) and enthalpic ([Delta]Ea) terms for homolytic bond cleavage in a variety of simple molecules. For loss of a methyl group from a short-chain n-alkane (<= C6), for example, we obtain an average [Delta]Ea of 42.0 cal/mol and an average Af*/Af of 1.021. Expressed differently, 13C-methane generation is predicted to be 2.4% (24[per mille sign]) slower than 12C-methane generation (from a short-chain n-alkane) in a sedimentary basin at 200°C but only 0.7% (7[per mille sign]) slower in a laboratory heating experiment at 500°C. Similar calculations carried out for homolytic bond cleavage in other molecules show that with few exceptions, [Delta]Ea varies between 0 and 60 cal/mol and Af*/Af between 1.00 and 1.04. Examination of this larger data set reveals: (1) a weak sigmoid relationship between [Delta]Ea and bond dissociation energy; and (2) a strong positive correlation between [Delta]Ea and Af*/Af. The significance of these findings is illustrated by fitting a kinetic model to chemical and isotopic data for the generation of methane from n-octadecane under isothermal closed-system conditions. For a specific temperature history, the fitted model provides quantitative relationships among methane carbon isotope composition, total methane yield and methane generation rate which may have relevance to the cracking of oil-prone kerogens and crude oil. The observed variability of the kinetic reactivity of various methane source rocks highlights the need to apply and adequately calibrate such models with laboratory data for specific study areas. With this approach isotope data of natural gases can be used not only to estimate the time of gas generation in a sedimentary basin, but also to evaluate the source rock maturities at which specific accumulations were generated, and place constraints on trap charging histories.

Cramer, B., E. Faber, et al. (2002). “Reaction kinetics of stable carbon isotopes in natural gas — insights from dry, open system pyrolysis experiments.” Fuel and Energy Abstracts 43(2): 130-130.

Open system nonisothermal pyrolysis with on-line compound-specific 13C/12C stable-isotope analysis (Py-GC/IRMS) has been performed on three carbonaceous sediments from NW Germany (Carboniferous, Westphalian coal, HI = 286 mgHC/gTOC, Ro = 0.72%), West Siberia (Cretaceous, Cenomanian shale, HI = 192 mgHC/gTOC, Ro = 0.43%), and Malaysia (Tertiary, Miocene coal, HI = 190 mgHC/gTOC, Ro = 0.36%). The study was focused on the generation of methane, ethane, and propane + propene. Measured δ13C-values of pyrolytically generated light hydrocarbons were in the range of δ13C-values commonly observed in thermogenic natural gas (−20 to − 40‰, PDB). While the isotopic composition of the pyrolysis products showed a general enrichment in 13C-species with increasing temperature, the isotopic trends of methane displayed characteristic structures involving reversals in certain temperature intervals. On the basis of the experimental data, reaction kinetic parameters have been derived for each isotopic species of the hydrocarbon gases assuming parallel first-order reactions and an Arrhenius-type temperature dependence. The resulting kinetic parameter sets for the Westphalian coal were then tentatively applied to geologic temperature histories to model the chemical and isotopic composition of natural gas generated and accumulated in reservoirs of the NW German Basin. The isotopic compositions (δ13C-values) of methane computed in this simulation show a good agreement with actual isotopic compositions of the natural gases in NW German gas fields. It is demonstrated that the combination of isotope-specific reaction kinetics with the regional thermal history provides a useful tool to account for variations in the isotopic composition of reservoir gases in the course of the accumulation history. These results indicate that, despite the undisputed differences between laboratory and natural conditions for gas generation, open system nonisothermal pyrolysis provides isotope-specific reaction kinetic parameters that satisfactorily describe the isotope effects associated with thermogenic natural gas generation in geologic systems. Application of these parameters in basin modeling studies permits prediction/reconstruction of isotopic compositions of natural gases with the same level of confidence as commonly applied bulk and compound-specific kinetic parameters.

Galimov, E. M. (2006). “Isotope organic geochemistry.” Organic Geochemistry 37(10): 1200-1262.

The present-day state as well as the history of isotope organic geochemistry is reviewed. Theoretical aspects of isotope fractionation in a system of complex organic molecules, fractionation of carbon isotopes in the biosphere, isotopes as applied to study the transformation of organic matter, geochemistry of oil and gas, evolution of the carbonate-organic carbon system and aspects of astrobiology are considered.

特点

1. 纯 Microsoft Excel VBA 加载宏程序
2. 直接应用 Excel 数据作图，无须数据转换
3. *输出是标准的 Excel 图表，可以在 Excel 中进行修改、修饰、输出、打印等操作
4. 程序可以绘制的图解可以任意修改、增删
5. 程序提供图解修改工具

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
附件是两个简单的地球化学图版定义文件示例（干酪根显微组分分类三角图.ini和热解S1+S2与有机碳判断源岩质量图.ini），使用时将它们复制到 GCDPlotdig 下面即可，并在GeoChemistryChart.ini中添加相关的图版信息即可，格式可参见文件中的其它定义。自定义一个新的石油地球化学图版可用软件中的config。作图效果见下图：

点击下载GCDPlot修改版包含石油地球化学图版
石油地球化学图版更新状态（2007年11月9日）：
.干酪根显微组分分类三角图
. 甲烷碳同位素-C1/(C1+C2)判断天然气成因（更正：应为 C1/(C2+C3),请自行在Config中修改 2007年12月5日）
.H/C-O/C范氏图,包括三类三分,三类四分,三类五分
.HI-Tmax有机质类型划分图版_三类四分
.热解S1+S2与TOC判断源岩质量图
.有机与无机二氧化碳鉴定图版
.d13CH4(甲烷碳同位素，下同)-CH4(%)识别甲烷成因图版
.d13C1-d13C2-d13C3不同成因有机烷烃气鉴别图版（戴金星，V型鉴别图版）
.d13C2 与d13C2-d13C1天然气成因鉴别图版

PS:对主程序进行了一些修改，修改默认作三角图时不能对数据自动进行归一化处理。对VB不熟，所以这样改的执行效率可能不好

进入VB编辑模式，修改如下：
Dim tri_sum As Double
‘定义一个新变量
…
…
For i = 1 To Count Step 1
‘数据转换：三角坐标到直角坐标 对x,y,z,作归一化处理
tri_sum = rngX.Cells(i, 1) + rngY.Cells(i, 1) + rngZ.Cells(i, 1)
x.Cells(i, 1) = GetXFromTernaryAxe(100 * rngX.Cells(i, 1) / tri_sum, 100 * rngY.Cells(i, 1) / tri_sum, 100 * rngZ.Cells(i, 1) / tri_sum)
y.Cells(i, 1) = GetYFromTernaryAxe(100 * rngX.Cells(i, 1) / tri_sum, 100 * rngY.Cells(i, 1) / tri_sum, 100 * rngZ.Cells(i, 1) / tri_sum)

2007/11/05 修改主程序，实现可以使用坐标轴次序反转
2007/11/6修改主程序，实现三角图坐标注。效果如下图：