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51.
青藏高原北部陆相盆地中烃源岩发育层位包括始新统风火山组、渐新统雅西措组和中新统五道梁组。古近系雅西措组烃源岩,特别是灰岩属于中好烃源岩范畴,有机质类型较好,且烃源岩主体处于成熟阶段,是藏北高原新生代陆相盆地主力烃源岩的发育层位。陆相盆地储集岩较发育,储层较丰富,发育层位包括风火山组和雅西措组,其中雅西措组是储层主力分布层位。对测区分析数据表明:通天河盆地具备一定规模的生油岩厚度,而且有机质丰度为沱沱河地区最高,表明其勘探前景较好。 相似文献
52.
逯向阳 《沉积与特提斯地质》2008,28(4):14-17
烃源岩有机质丰度的恢复具有重要的现实和理论意义。笔者在对比多种方法的基础上,对大民屯凹陷的烃源岩的有机质丰度进行了恢复。 相似文献
53.
Apatite fission-track (AFT) thermochronological modeling as a diagnostic tool for periods of stability (peneplanation) and tectonic activity (orogeny) has been broadly used in tectonic studies of Central Asia in recent years. We discuss more than 100 AFT ages of samples from the Kyrgyz Tien Shan and Altai and compare them with AFT data from northern Kazakhstan. Geological, geomorphological, and AFT data indicate intense activity in the Late Cenozoic Eurasian continental interior. The impact from the India-Eurasia collision on the northern Tien Shan, Altai, and northern Kazakhstan regions showed up at 11, 5, and 3 Ma, respectively, as a result of stress propagation into the continent, with the ensuing reactivation and mountain growth. We hypothesize that a distant effect of the Late Cenozoic India-Eurasia collision was to rejuvenate Paleozoic fault zones and to deform the Mesozoic sedimentary cover north of the collision front as far as the West Siberian Plate. The reactivation facilitated formation of tectonic oil and gas traps. The activity in northern Central Asia under the effect of the Indian indentation into Eurasia appears to continue and may evolve to include uplift of southern West Siberian plate with uplift. 相似文献
54.
节理岩体卸荷强度特性的试验研究 总被引:2,自引:0,他引:2
卸荷状态工程岩体的强度特性与传统的加载岩体有本质的区别。目前对于岩石卸荷强度特性的研究比较多见,但对于含节理的岩体在卸荷应力状态下的强度特性,尤其是节理面对其强度的影响研究实属少见。本文通过岩体三轴模拟试验研究了卸荷应力状态下节理岩体的破坏特征,突出考虑了节理面性质对卸荷强度的影响,在此基础上提出了节理岩体卸荷强度准则的一般表达式并进行了对比验证。 相似文献
55.
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57.
Sukanta Roy Labani Ray Anurup Bhattacharya R. Srinivasan 《International Journal of Earth Sciences》2008,97(2):245-256
The Late Archaean Closepet Granite batholith in south India is exposed at different crustal levels grading from greenschist
facies in the north through amphibolite and granulite facies in the south along a ∼400 km long segment in the Dharwar craton.
Two areas, Pavagada and Magadi, located in the Main Mass of the batholith, best represent the granitoid of the greenschist
and amphibolite facies crustal levels respectively. Heat flow estimates of 38 mW m−2 from Pavagada and 25 mW m−2 from Magadi have been obtained through measurements in deep (430 and 445 m) and carefully sited boreholes. Measurements made
in four boreholes of opportunity in Pavagada area yield a mean heat flow of 39 ± 4 (s.d.) mW m−2, which is in good agreement with the estimate from deep borehole. The study, therefore, demonstrates a clear-cut heat flow
variation concomitant with the crustal levels exposed in the two areas. The mean heat production estimates for the greenschist
facies and amphibolite facies layers constituting the Main Mass of the batholith are 2.9 and 1.8 μW m−3, respectively. The enhanced heat flow in the Pavagada area is consistent with the occurrence of a radioelement-enriched 2-km-thick
greenschist facies layer granitoid overlying the granitoid of the amphibolite facies layer which is twice as thick as represented
in the Magadi area. The crustal heat production models indicate similar mantle heat flow estimates in the range 12–14 mW m−2, consistent with the other parts of the greenstone-granite-gneiss terrain of the Dharwar craton. 相似文献
58.
应用生烃动力学法研究川东上二叠统烃源岩生烃史 总被引:3,自引:2,他引:1
现今川东上二叠统烃源岩生烃史研究具有局限性.首先,没有对上二叠统Ⅰ-Ⅱ1型灰岩生油、Ⅲ型泥岩的生气史分开评价;其次,海相镜质组反射率通过拟合公式换算成镜质体反射率评价烃源岩成熟度具有局限性.针对上述不足,笔者通过热模拟实验,利用化学动力学方法,标定出两类源岩生油、生气的动力学参数,并结合川东地区的埋藏史及热史,模拟出源岩有机质的成烃转化率曲线.研究表明:上二叠统灰岩、泥岩有机质在距今200 Ma和190 Ma分别进入了生油、生气门限,而在距今170 Ma和140 Ma生烃结束. 相似文献
59.
Rock magnetic record of Cenozoic lake sediments from the Linxia basin and aridification of the Asian inland 总被引:1,自引:0,他引:1
High resolution research of rock magnetic records and quartz sands from the Maogou Section in the Linxia basin reveals that
after a relatively stable environment between 13.07 Ma and 8.6 Ma, the basin was gradually influxed by eolian dusts at about
8.6 Ma, with two rapid increases at about 6.4 Ma and 5.3 Ma, respectively. The study suggests that drying of northwest China
began at 8.6 Ma and strengthened rapidly at about 6.4 Ma and 5.3 Ma.
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Translated from Marine geology & Quaternary geology, 2007, 27(4): 103–110 [译自: 海洋地质与第四纪地质] 相似文献
60.
Zhanhong LIU Sitian LI Renchen XIN Changgui XU Jianchun CHENG 《Frontiers of Earth Science》2008,2(1):73-82
Bohaiwan basin, covering an area of 200 000 km2, is one of the most important oil-bearing basins in Eastern China. Rifting processes formed the basin, and two evolution
phases can be recognized. The rifting phase developed in Paleogene, and post-rifting phase occurred in Neogene. More than
200 oil fields have been found in the onshore and offshore area in Bohaiwan basin in recent years. The distribution of the
oil fields is closely related to the rich hydrocarbon depressions, and the Huanghekou depression is one of these rich hydrocarbon
depressions. A number of large and medium-sized oil and gas fields have been found in this area, such as BZ25-1, BZ34 etc.,
and the hydrocarbon was mainly from the Huanghekou depression. The formation of rich hydrocarbon source rocks depended on
the tectonic setting of rapid subsidence, favorable paleoclimatic conditions and paleolimnology environments. The effects
of paleoclimatic condition on hydrocarbon source rocks are the focus of this paper.
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Translated from Geological Bulletin of China, 2007, 26(7): 830–840 [译自: 地质通报] 相似文献