2013 Vol. 35, No. 4

Display Method:
2013, 35(4)
Abstract:
Main geological features and accumulation models of abnormally high-pressured gas reservoirs in Tarim Basin
Wu Genyao, Zhu Defeng, Liang Jiangping, Yang Jianguo, Zhao Yan
2013, 35(4): 351-363. doi: 10.11781/sysydz201304351
Abstract(1321) PDF-CN(993)
Abstract:
The abnormally high-pressured gas reservoirs were well developed in the Tarim Basin. It was discussed in this paper the abnormally high pressures in foreland depressions, including regional evolution, contributing factors, formation of gas-bearing structures, accumulation mechanisms and periods, and then presenting accumulation models for the Kuqa Depression and the Yecheng Sag respectively. The keys for abnormally high-pressured gas reservoirs and the exploration targets were studied. There were 6 abnormally high-pressured gas reservoirs in Kuqa area, 5 of which were late-charged while only the Yinan2 gas reservoir was self-sourced. The main accumulation period was from the Late Miocene to the Early Pliocene. Anticlines were controlled by a group of overstep reverse faults. Natural gas charged into gas-bearing structures directionally due to the structural compression since Pleistocene. Self-sourced high pressure and transitional high pressure together formed abnormally high pressure. The deep Paleogene gas reservoir in the Kekeya anticline of Yecheng Sag, namely, the Kalata'er gas reservoir, accumulated in Miocene and adjusted with stratigraphic folding in Pliocene-Early Pleistocene, which was an abnormally high-pressured gas reservoir of late-adjustment type. The shallow Miocene gas reservoir in the Kekeya anticline was late-charged, with both the source beds (the Carbono-Permian and Jurassic) and the deep Paleogene gas reservoir supporting gases, which should be a later secondary-generated accumulation.
Hydrocarbon origin and accumulation model of Kedong-Kekeya tectonic belt in piedmont of West Kunlun Mountain
Mo Wuling, Lin Tong, Zhang Ying, Yi Shiwei, Wang Dongliang, Zhang Liang
2013, 35(4): 364-371. doi: 10.11781/sysydz201304364
Abstract(3245) PDF-CN(848)
Abstract:
In the foreland of Western Kunlun Mountain, 3 sets of hydrocarbon source rock developed, including the Heshilafu Formation in the Lower Carboniferous, the Pusige Formation in the Lower Permian and the Yangye Formation in the Middle Jurassic. Analysis of source rock distribution, hydrocarbon property, oil-source and gas-source correlation in the Kedong-Kekeya tectonic belt in the foreland of Western Kunlun Mountain led to the fo-llowing 2 conclusions: a) Oil in the Kedong-Kekeya tectonic belt mainly originated from relatively highly-mature organic matter of type Ⅱ in Permian. b) Natural gas mainly came from Permian, and partially from Jurassic and Carboniferous. Based on the study of tectonic evolution, fluid inclusions and hydrocarbon accumulation evolution history of the well Kedong 1 and the Kedong-Kekeya tectonic belt, the author analyzed the accumulation process of hydrocarbon and summarized the accumulation model of hydrocarbon in the Kedong-Kekeya tectonic belt. Accumulation process of hydrocarbon in the Kedong-Kekeya tectonic belt can be divided into 4 periods which include initial charging period of oil, oil-charging window, gas-charging window and hydrocarbon-adjusting period. To figure out the source and accumulation process of hydrocarbon in the Kedong-Kekeya tectonic belt can provide important reference to expand exploration scope and find more petroleum resource in the study area.
Sequence stratigraphic division of Cambrian in western Hunan-Hubei and applications for petroleum exploration
Wang Bijin, Bao Hanyong, Guo Zhanfeng, Chen Miankun
2013, 35(4): 372-377. doi: 10.11781/sysydz201304372
Abstract(1467) PDF-CN(838)
Abstract:
The systematic analyses of outcrops and drilling profiles and the tests of reservoir samples and dark mudstones from Cambrian in the western Hunan-Hubei indicate that the Cambrian in the study area can be divided into 6 third-order sequences, and the sequence boundaries are mainly unconformity surfaces and lithologic transitional surfaces. Oolitic limestones/dolomites are the most favorable reservoirs in Cambrian. They mainly distribute in the transgressive system tract of sequence 5, and a few of them locate in the highstand system tract of sequences 4 and 5. The content of total organic carbon (TOC) varies obviously among dark mudstones in the Lower Cambrian. The dark mudstones rich in TOC distribute in the highstand system tract of sequences 1, while those in the upper formation have lower TOC content. The transgressive system tract of sequence 5 which deve-lops thick oolitic limestones/dolomites is the main target for normal exploration. The highstand system tract of sequences 1 which has higher TOC content is the main target for shale gas exploration.
Diagenesis and favorable diagenetic facies of Chang8 reservoir in Jiyuan area of Ordos Basin
Ma Haiyong, Zhou Lifa, Zhang Xiaogang, Han Tianyou, Li Jihong, Liu Guanglin
2013, 35(4): 378-383. doi: 10.11781/sysydz201304378
Abstract(1371) PDF-CN(857)
Abstract:
The diagenesis and favorable diagenetic facies of Chang8 reservoir in Jiyuan area of the Ordos Basin were studied by means of cast thin section, SEM and reservoir comprehensive evaluation. The Chang8 sandstones were during the subphase A of late diagenesis. Compaction effect caused the disappearance of primary pores. Influenced by acidic diagenetic environment, feldspars were corroded, improving pore connectivity and permeability. In the well-developed chlorite film which generated during early stage, a large quantity of primary pores was preserved, showing good reservoir physical property. According to diagenetic and sedimentary features, 4 diagenetic facies belts were classified. The diagenetic facies belts of feldspar corrosion and chlorite film-intergranular pore were most favorable, mainly distributing in sandbody zones in subaqueous distributary channel of delta front in Liumaoyuan and Baoziwan areas, and in distributary channel of delta in Xiaojianzi area.
Fluid inclusions of Chang2 and Chang6 sections in Yanchang Formation, Panlong area, Ordos Basin
Cao Qing, Zhao Jingzhou, Liu Yiqun
2013, 35(4): 384-388. doi: 10.11781/sysydz201304384
Abstract(1442) PDF-CN(701)
Abstract:
With methods such as polarizing and fluorescence microscope observation, homogeneous temperature and ice point temperature measurement and analysis of composition, a systematic study was conducted to acquire petrographic, salinity and homogenization temperature of fluid inclusions in the Yanchang Formation of the Triassic reservoir in the Ordos Basin. Combined with the thermal evolution of basin, fluid injection history and corresponding paleo-fluid potential were constituted. The oil and gas accumulations of reservoirs in the Chang2 and Chang6 sections were characterized by one stage, and might happen in the Middle Cretaceous, about 120-100 Ma.
Fluid inclusion features and hydrocarbon accumulation stages of Permian Longtan Formation, Huangqiao area, Lower Yangtze Basin
Chen Shunyong, Yu Hao, Lin Chunming, Zhang Ni, Zhang Xia, Ni Pei, Ding Junying
2013, 35(4): 389-394. doi: 10.11781/sysydz201304389
Abstract(1836) PDF-CN(920)
Abstract:
Transmitted light and fluorescence microscopy observations of fluid inclusions indicate that fluid inclusions are widespread in the Permian Longtan Formation in Huangqiao area of the Lower Yangtze Basin, mainly aqueous and oil inclusions. They usually distribute in small sizes in quartz cracks and quartz secondary enlargement edges. Oil inclusions show yellow-green and blue-white fluorescents respectively with blueray and ultraviolet excitations, thus indicating that the oil in the Longtan Formation in the study area is primarily in middle mature stage. Through the microscopic temperature measurement of inclusions, combined with the burial history-thermal history, tectonic evolution and diagenetic evolution model researches, it has been concluded that the homogenization temperature of inclusions has 3 intervals, 89-93, 115.4-126.3 and 135-147.6℃. Hydrocarbons in the Longtan Formation in Huangqiao area have experienced 3 major filling periods: the first period for 73-70 Ma (the Late Cretaceous), the second period for 58-52 Ma (the Early Paleogene), the third period for 45-38 Ma (the Middle Paleogene). The second and third stages are most important.
Accumulation system and controlling factors of fault-lithologic reservoirs of Dainan Formation in Gaoyou Sag, Northern Jiangsu Basin
Dong Caiyuan, Liu Zhen, Liu Qidong, Luo Beiwei, Li Chuhua, Wang Weijun
2013, 35(4): 395-400. doi: 10.11781/sysydz201304395
Abstract(1328) PDF-CN(686)
Abstract:
Based on the studies of fault sealing evolution, oil-bearing formation and hydrocarbon generation ability of highly-conductive mudstones in the Dainan Formation, the fault-lithologic reservoir systems of the Dainan Formation in the Gaoyou Sag have been classified into 3 types, including self-sourced, other-sourced and mixed-sourced. The self-sourced accumulation systems mainly locate in the deep Shaobo and Fanchuan Sags, and the Shaoshen1 resrvoir is typical. The other-sourced accumulation systems mainly distribute in the Majiazui, Zhou22 and Shao18 reservoirs. The mixed-sourced accumulation systems are represented by the Lian3, Lian7 and Yong22 reservoirs. The fault-lithologic reservoirs of the Dainan Formation in the Gaoyou Sag are controlled by2 elements, oil source and migration pathway. The favorable zones for exploration include Huangjue-Majiazui, Lianmengzhuang-Yongan and Caozhuang-Xiaoliuzhuang.
Difference of micro-pore throat characteristics in extra-low permeability sandstone of different pore throat matching relationship
Gao Hui, Jing Xiaofeng, Zhang Lan
2013, 35(4): 401-406. doi: 10.11781/sysydz201304401
Abstract(1358) PDF-CN(978)
Abstract:
There are different pore throat matching relationship and micro-pore throat characteristics for similar or equal sandstones because of different deposition and diagenesis reconstruction. Taking the Chang6 sandstone of Yanchang Formation in Wuqi area and the X2 sandstone of Xishanyao Formation in Niujuanhu area as the objects, the micro-pore throat characteristics in different pore throat matching relationships are evaluated quantitatively using physical property testing, cast section and constant rate mercury penetration technique. The results show that there are no obvious differences in pore parameters, and the differences of micro-pore throat characteristics are mainly presented in throat parameters for samples with different permeabilities. As to the X2 sandstone, the generation of dissolution pores and intercrystal pores leads to high content of curved lamellar and tube bundle throat, small throat radius and narrow distribution, concentrated contribution of throat to permeability, fine average throat radius and main flow throat radius, high content of big pore throat ratio in Niujuanhu area. In the Chang6 sandstone, necking, flaky and curved lamellar throats develop, throat radius vary obviously, and big throats are in high content, which can be explained by the generation of primary intercrystal pores. Different steps should be taken in the development process for extra-low permeability sandstone reservoirs which present different pore throat matching relationships.
Response of Cenozoic Tan-Lu fault activity in Laizhou Bay area, Bohai Sea
Wu Guoqiang, Lü Xiuxiang, Zhou Xinhuai, Yu Yixin, Tian Ya, Jiang Ziwen
2013, 35(4): 407-413. doi: 10.11781/sysydz201304407
Abstract(1483) PDF-CN(1077)
Abstract:
By using the latest 3D seismic data, we described the space distribution of the Tan-Lu fault in the southern Bohai area and analyzed the evolution history and the influence to sedimentation and tarp formation combining the previous research achievements. The results showed that: in the southern Bohai area, flower structure and formation dag were revealed in the Tan-Lu fault and the salt activity was also a strong evidence for the strik-slip movement of the Tan-Lu fault in Cenozoic. The activity of the Tan-Lu fault had a significant impact on the evolution of the Laizhou Bay Sag, mainly reflected by the migration of sedimentary center. It also led to the formation of traps in both deep and shallow layers and most of the traps were faulted anticlines and fault blocks.
Confirmation and distribution features of effective source rocks in Yinger Sag, Jiuquan Basin
Gao Gang, Wang Yinhui, Liu Guangdi, Chen Jianjun, Zhou Yibo, Zhou Zaihua, Yang Zhiming
2013, 35(4): 414-418. doi: 10.11781/sysydz201304414
Abstract(1404) PDF-CN(783)
Abstract:
Based on the basic theory of hydrocarbon generation and expulsion of source rock, TOC content, pyrolysis parameter S1 and chloroform bitumen "A" content have been correlated to confirm the lowest limit of TOC content of effective source rocks from the Lower Cretaceous in the Yinger Sag. The lowest limit of TOC content of effective source rocks from the Xiagou Formation is 0.8%, while that from the Chijinbu Formation is 0.6%. Combining with the prediction from TOC content by single well logging, the thickness of effective source rock in single well has been calculated. The distribution of effective source rock in main layers has been confirmed combining the studies of sequence stratigraphy and sedimentology. Effective source rocks are well-developed in each layer, among which those in the Chijinbu Formation have the biggest thickness, and the Upper Xiagou Formation the second. In the Lower Xiagou Formation, effective source rocks are thin; however, they may increase to 250 m thick in the northern subsag, and 200 m thick in the southern subsag.
Petroleum accumulation characteristics in Campos and Santos Basins, offshore Brazil
Xiong Liping, Wu Changwu, Guo Yongqiang, Li Songyang
2013, 35(4): 419-425. doi: 10.11781/sysydz201304419
Abstract(1604) PDF-CN(1141)
Abstract:
The Campos and Santos Basins are rich in petroleum. Both of the 2 basins have experienced 3 phases of tectonic evolution (rift, transition and passive continental margin), depositing 3 corresponding sedimentary mega-sequences (pre-salt continental sequence, salt sequence and post-salt marine sequence), and forming 2 plays (pre-salt play and post-salt play). Due to different tectonic frameworks, salt distribution and pre-salt reservoir development patterns are different in the 2 basins. Combining with different post-salt reservoir distribution, obvious difference exists in petroleum distribution between the 2 basins. Petroleum in the Santos Basin mainly distributes in pre-salt sequences of the outer basement plateau while petroleum in the Campos Basin accumulates in post-salt reservoirs of the central low uplift. Based on the analyses of tectonic evolution, sedimentation characteristics and major controlling factors, the favorable exploration zones for pre-and post-salt reservoirs are defined. The differences of accumulation condition between the 2 basins are discussed. The studies may provide Chinese companies a guide for new business development and executing blocks' exploration activities in the 2 basins.
Oil and source rock correlation of lower assemblage of Yanchang Formation in Wuqi and Dingbian areas, Ordos Basin
Wang Xiangzeng, Ren Laiyi, Zhang Lixia, He Yonghong, Yang Chao, Duan Xinting
2013, 35(4): 426-431. doi: 10.11781/sysydz201304426
Abstract(1336) PDF-CN(795)
Abstract:
The geochemical correlation of source rock and crude oil from the lower assemblage (Chang7, 9, 10, respectively) of the Yanchang Formation has indicated that, the carbon preference index (CPI) of the Chang7 source rock is 1.2, and that of the Chang9 and Chang10 source rocks is 1.09. The odd-even predominance (OEP) of carbon disappears in the Chang7, 9, 10 source rocks. In the Chang7 source rock, the relative content of Ts is higher than that of Tm, while in the Chang9 and Chang10 source rocks, the relative content of Ts is lower than that of Tm, indicating for higher maturity of the Chang7 source rock. The C27, C28, C29 ααα20R regular steranes of the Chang7 source rock distribute in "V" and "L" shapes, and those of the Chang9 source rock in nearly "V" and anti-"L" shapes, and those of the Chang10 source rock in anti-"L" shape. Crude oil in the Chang8 strata mainly originated from the Chang7 source rock in the west of the study area, and from both the Chang7 and Chang9 source rocks in the east and south. Crude oil in the Chang9 strata mainly originated from the Chang10 source rock in the west of the study area, and from both the Chang9 and Chang10 source rocks in the east and south. Crude oil in the Chang10 strata originated from both the Chang10 and Chang9 source rocks in the south.
Geochemical characteristics and distribution rules of oil shale from Yanchang Formation, Southern Ordos Basin
Deng Nantao, Zhang Zhihuan, Ren Laiyi, Wang Fubin, Liang Quansheng, Li Yuxiang, Li Wenhao, Zhao Shuangfeng, Luo Mengjiao
2013, 35(4): 432-437. doi: 10.11781/sysydz201304432
Abstract(1712) PDF-CN(945)
Abstract:
Based on the geochemical features and logging data of dark mudstone, carbonate mudstone and oil shale samples from different layers of the Yanchang Formation in the southern Ordos Basin (including Zhengjing, Binchang, Xunyi and Fuxian areas), the identification markers and distribution characteristics of oil shale have been investigated. The result shows that there are significant differences in biomarker characteristics, hydrocarbon generation potential and logging electrical characteristics. Oil shale has typical geochemical and geophysical composite identification marks. The distribution of oil shale is significantly controlled by sedimentary environment. Deep or semi-deep lacustrine facies which is near to the center of lake basin is the main development zone for oil shale.
Identification of chief hydrocarbon source rocks in Lishu Fault Depression and their geochemical characteristics
Song Zhenxiang, Zhou Zhuoming
2013, 35(4): 438-444. doi: 10.11781/sysydz201304438
Abstract(1561) PDF-CN(714)
Abstract:
Based on the hydrocarbon generation potential of 4 sets of source rocks developed in the Lishu Fault Depression, the results illustrated that the chief hydrocarbon source layer is K1sh and the secondary layer is K1yc; meanwhile, the effective source rocks of K1h and K1d formations only developed in some certain areas. We made a cluster analysis to source rock samples (TOC>0.5%) based on more than 20 variables, and the results have shown that the source rock samples can be divided into 4 types and the geochemical characteristics of 4 types of source rocks are different in many respects, such as sedimentary environment, hydrocarbon generation potential, origin of organic matters and maturity stages. Type C and D source rocks have the highest hydrocarbon generation potential and they have good comparability with crude oils. Taking into account the plane distribution of source rocks, type C source rocks mainly distribute in Siwujiazi, Pijia and Sangshutai deep depressions with deep lake facies. Meanwhile, type A, B and D source rocks mainly distribute in Sujiatun sag, Shuanglong sag and Taipingzhuang, Qikeshu, Qinjiatun areas along the basin margins with shallow lake facies, semi-deep lake facies and swamp subfacies within delta plain sedimentary environment.
Micro-seepage of hydrocarbon gas in mudstone and sandstone and its significance for oil and gas exploration
Huang Chenjun, Wang Guojian, Lu Li, Yang Fan, Gao Junyang
2013, 35(4): 445-448. doi: 10.11781/sysydz201304445
Abstract(1280) PDF-CN(616)
Abstract:
Two mini apparatus were initially made and employed for the experimental simulation of hydrocarbon gas micro-seepage through mudstone and sandstone separately. It was found out that the ratio of hydrocarbon gas components would maintain stable if they had reached the balance state in a certain sampling point and the balanced componential percentage in the total hydrocarbon was in positive correlation with the distance between sampling point and hydrocarbon resource. These characters of hydrocarbon micro-seepage have two pieces of significance: On one hand, the balance time could be calculated through experimental research or field measurement. According to the balance time, the micro-seepage velocity of hydrocarbon gas could be accounted, as well as the micro-seepage amount of hydrocarbon gas from a reservoir further according to micro-seepage model. On the other hand, through the study of the characteristics of the vertical curve of hydrocarbon componential percentage in total hydrocarbon tested from core geochemical exploration or hydrocarbon gas logging, the depth of a potential reservoir is likely to be predicted.
Source rock study and accumulation pattern of Funing Formation in Yancheng Sag, Northern Jiangsu Basin
Ji Yaqing, Liu Yimei, Feng Wujun
2013, 35(4): 449-452. doi: 10.11781/sysydz201304449
Abstract(1426) PDF-CN(698)
Abstract:
The studies of source rocks from the Funing Formation in the Yancheng Sag of the Northern Jiangsu Basin have indicated that the 2nd member of the Funing Formation is most favorable for hydrocarbon generation. Maturity parameters analyses and structural diagram of seismic reflection on the top of the 2nd member of the Funing Formation have shown the maturity and expulsion ranges of source rocks in the Funing Formation. Meanwhile, through the studies of relevant reservoirs, it has been stated briefly that the bottom sand bodies of the 3rd member of the Funing Formation are most favorable for the accumulation of hydrocarbons which generate from the 2nd member of the Funing Formation. 2 hydrocarbon accumulation models may exist in the Yancheng Sag, including "bottom source and top reservoir"and "top source and bottom reservoir". Deep sags near to big faults are the most favorable targets for petroleum exploration.
Difficulties and solving strategies for integrated physical simulation of tectonic deformation and hydrocarbon charging
Wang Xuejun, Shan Yixian, Lao Haigang, Wang Yong, Cui Yingbin
2013, 35(4): 453-456. doi: 10.11781/sysydz201304453
Abstract(1217) PDF-CN(677)
Abstract:
Complex fracture belt in petroliferous basin has extremely important geological significance, which not only embodies basin tectonic deformation, but also serves as the target for petroleum migration and accumulation. Through the comparison of domestic and foreign oil and gas injection experiments, the key technical problems of tectonic deformation and hydrocarbon injection experiments were studied, such as the protection of tectonic model, the problem of sealing up and the problem of hydrocarbon coloring. Through the improvement of device, the tectonic model was protected and the secondary deformation was prevented. Sealants of different types were designed to meet the needs of different parts of the model. For the distortion of hydrocarbon migration, color absorbing medium was added. The modeling experiment can reproduce the real underground structure deformation and hydrocarbon charging process.
Multiparameter cluster analysis of crude oil type in Shahejie Formation, southern slope of Niuzhuang sub-Sag
Song Chengpeng, Luo Xiaorong, Hao Xuefeng, Xiang Lihong, Liu Keqi, Zhang Likuan, Lei Yuhong, Cheng Ming, Yang Bin
2013, 35(4): 457-463. doi: 10.11781/sysydz201304457
Abstract(1253) PDF-CN(655)
Abstract:
Multiple geochemical parameters of isoprenoid hydrocarbon, individual hydrocarbon carbon isotope, gonane and terpane in source rock extraction content components from the Niuzhuang sub-Sag were compared. Biomarkers such as phytane, gammacerane, homohopane series dinosterane and 4-methylsteranes were regarded as the fingerprint parameters of source rock features. According to clustering analyses, crude oils from the Shahejie Formation were classified into 3 genetic types as followed. The crude oils of type Ⅰ clustered with the source rocks from the 3rd member of the Shahejie Formation, and were featured by low contents of phytane, gammacerane, C35 homohopane, dinosterane and 4-methyl αααC29 steranes, showing the geochemical characteristics of source rocks in the lower part of the 3rd member of the Shahejie Formation which developed in weak oxidizing and low salinity environment. The crude oils of type Ⅱ clustered with the source rocks from the 4th member of the Shahejie Formation, and were featured by high contents of phytane, gammacerane, C35 homohopane, dinosterane and 4-methyl αααC29 steranes, showing the geochemical characteristics of source rocks in the upper part of the 4th member of the Shahejie Formation which developed in strong reducing and high salinity environment. The crude oils of type Ⅲ had no significant clustering relationship with the source rocks from the 3rd and 4th members of the Shahejie Formation, but the average value of main clustering parameters was in the range of the above-mentioned source rocks, indicating that the crude oils of type Ⅲ might be the mixture of type Ⅰ and Ⅱ.
Experimental study of nonlinear seepage for heavy oil
Wang Weiying, Yu Gaoming, Ke Wenli, Wang Yu, Ge Yue
2013, 35(4): 464-467. doi: 10.11781/sysydz201304464
Abstract(1567) PDF-CN(743)
Abstract:
Due to the non-Newtonian behavior of heavy oil, the seepage characteristics in porous medium are different from conventional crude oil. They usually seep in nonlinear ways and there might exist threshold pressure gradients. Only when the displacement pressure gradient is greater than the threshold pressure gradient, heavy oil begins to flow, and the seepage rule deviates from Darcy's law. Through laboratory experiments, this paper designs a method for measuring threshold pressure gradient appropriately. Natural core samples and simulated oil are used to measure threshold pressure gradient by setting different flow rates. In this way, the impact of flow rate on threshold pressure gradient is studied. The results show that the threshold pressure gradient would be affected when the displacing rate exceeds a critical value. Therefore, in the process of measuring real threshold pressure gradient of a core, the choice of experimental method and displacing rate can not be ignored.
Application of Leica QWin_V3 image analysis software in organic petrologic quantitative study
Xie Xiaomin, Tenger, Yang Yunfeng, Hu Mingxia, Bian Lizeng
2013, 35(4): 468-472. doi: 10.11781/sysydz201304468
Abstract(1499) PDF-CN(719)
Abstract:
The quantitative analysis of whole rock macerals is a complex job for organic petrology. The Leica QWin_V3 image analysis software can select the macerals with similar gray scale or color and make quantitative analysis in selected area, such as circumference, diameter and so on. Area quantitative statistics of whole rock macerals of coal samples have proved that this software succeeds in organic petrologic quantitative study.