| The generation, migration, accumulation and etc. of oil and gas are seriouslyaffected by the stratum denudation, by which the original and present-day basinfillings and sediments are distinct from each other. So, it is limited that is thefarther research on the history of basin's structure evolvement, the history ofbasin's filling, the history of deposit evolvement, heat history and the history ofoil-gas store, and etc.. Therefore, restoration and determination of the stratumdenudation calculation is significantly basic work during the basin analysis.There are many methods to restore the denudated thickness of the stratum, andthe common methods include stratigraphic correlation, sedimentation rate, trendprolongation of the undenudated stratum, acoustic transit time, optimum estimationby porosity data, substance equity, vitrinite reflectance, the analysis of apatitefission track, cosmogenic nuclide analysis, sediment basin wave process analysis,and etc..Xijiang Tarimu basin is one of the uppermost petroleum provinces. So,exploration and development for the petroleum in the basin plays an important parton relieving the demand for petroleum in our country. Comparing with otherpetroleum province in China, research extent of Tarimu basin is lower, and itspotential is immense. There are more than 30 wells in Kongquehe area of Tarimubasin, in which the industry oil current produced by cao 2 well, lunnan 59 well, andyingnan 2 well, while the oil and gas was found in cao 1 well, cao 3 well,cao 4well, kunan 1 well, weima 1 well, longkou 1 well, huayingcan 1 well and yingnan1well. Though there is oil-gas produced, the success odds of drilling are small.Hence, the distribution, characteristics, reserves, producing hydrocarbon, thesecondary generation hydrocarbon, and etc. of the source rocks in Kongquehe area,need to be studied in detail. The great formation movements had been undergonetime after time since Sinian on Kongquehe area, such as Caledonian,Hercinian,Indosinian,Yanshanian and Himalayan period, and multi-territorial unconformitysurfaces came into being. Repetitious courses, including sediment, rising,denudation, redeposition, rerising, and redenudation of the stratum, resulted in thevariety rule of original porosity data, compaction, paleo-geotherm, Ro, and etc. ofthe stratum under unconformity surfaces, were destroyed. Thus, one of the mostimportant tasks is to restore the denudation thickness of the unconformity surfaces,in order to study the hydrocarbon source rocks of this area. Based on the circumstances, in which the wells distribute asymmetrically,data are few, and the restoration research on the denudation thickness is little, themethod of "taking the point to control the plane"was adopted, that is to control thedenudation thickness restoration corresponding to the top by using the calculationresult of Jurassic, Carboniferous, Silurian and Ordovician by the research regionaland wells. The main means used is Ro method, acoustic transit time method andsedimentation rate method. Denudation thickness of 21 wells was obtained in total.In addition, 1328 denudation thickness values and 664-denudation thicknessnumerical value dots in the plane were worked out; also, 1418 ancient hiddendeposit values and 709 numerical dots were obtained, by which the ichnography ofthe denudation quantity on the top of the Jurassic, Carboniferous, Silurian, andOrdovician was finished, at the same time, the maximal ancient deep burying mapof Jurassic, Carboniferous, Ordovician and Cambian-Lower Ordovician wascompleted too. The top of Jurassic, which is one of the dominated denudation planes inKongquehe area, is corresponding to T4 seismic reflection stratum, which was is in 0the stage of rift lacustrine basin, whose denudation quantity ranges from 330m to1150m. In the area distribution, the dominated trend is that the north is high, thesouth is low, the east is high, and the west is low. Concretely, the denudationquantity in the north of Kongquehe incline and nose-uplift area of Kuerle is large,while the denudation quantity in the south of the incline, and the depression ofcaohu, yingjisu and manjiaer is small. The top of Carboniferous, which was in the craton depression phase, iscorresponding to T5 seismic reflection stratum. The denudation quantity ranges 0from 100m to 770m. Carboniferous in Kongquehe area is only distributed in caohudepression. In the area distribution, the leading trend is that the south and the northare high, the middle part is low, the east is high, and the west is low. Concretely, thedenudation quantity in the middle part of caohu depression is small, while thedenudation quantity at the edge of the depression is large. The top of Silurian, which was in the extrusion-upheaving phase, iscorresponding to T6 seismic reflection stratum. It is one of the leading denudation 0planes, whose denudation quantity ranges from 580m to 3600m. In the areadistribution, the dominated trend is that the north is high, the south is low, themid-east is high, and the east and the west are low. Concretely, the denudationquantity in the north of Kongquehe incline and nose-uplift area of Kuerle is large,while the denudation quantity in the south of the incline, and the depression ofcaohu, yingjisu and manjiaer is small. Also, the top of Ordovician is one of the central denudation planes inKongquehe area. It was in the sub-phase of aulacogen'filing and dieing out andis corresponding to T7 quake reflection stratum, whose denudation quantity ranges 0from 210m to 3400m. In the area distribution, the dominated trend is that the northis high, the south is low, the middle part is high, and the east and the west are low.Concretely, the denudation quantity in the north of Kongquehe incline and thenose-uplift of Kuerle is large, while the denudation quantity in the south of theincline, and the depression of caohu, yingjisu and manjiaer is small. The maximal Paleozoic burial depth of the top of Jurassic, Carboniferous,Ordovician, Cambian-Lower Ordovician, is mostly the present-day burial deposit.Thereinto, the maximal ancient burial deposits of the top of Carboniferous allbelong to the present-day ones, whose burial deposit ranges from 2900m to 4900m.The four small areas, which located in the north of the top of Jurassic, reached themaximal ancient burial depth in the end period of Jurassic, whose burial depthranges from 500m to 1200m. The area, present in the north edge of the east and in the east deflection of themiddle part in the top of Ordovician, reached the maximal Paleozoic burial depth atthe end of Silurian. The burial depth in the top of Ordovician ranges from 1400m to6200m. There are four pieces of area reaching the maximal Paleozoic burial depthat the end of Silurian, which exists near the north of the middle, east area inCambian-Lower Ordovician. The burial depth of Cambian-Lower Ordovicianranges from 2100m to 11900m. Based on denudation quantity value of the top restoration of Jurassic,Carboniferous, Silurian and Ordovician, in combination with the maximalPaleozoic burial depth value of Jurassic, Carboniferous, Ordovician andCambian-Lower Ordovician, the acquirement of the maximal paleo-geotherm wasdetermined. Also, the history of producing hydrocarbon of the four main sourcerocks including Jurassic, Carboniferous, Ordovician and Cambian-LowerOrdovician, can be restored quasi-quantificationally. The source rock of Jurassic,which located in the south of Kongquehe incline, caohu depression and yingjisudepression entered generation of hydrocarbon threshold. Source rocks ofCarboniferous situated in caohu depression come into the hydrocarbon-generatingthreshold in the Cretaceous period. However, the source rocks of Ordovicianentered hydrocarbon-generating threshold in the period of Ordovician, andCambian-Lower Ordovician source rocks entered hydrocarbon-generatingthreshold during the period of Lower Ordovician. Research on the denudation quantity restoration of Kongquehe area is little.Only the denudation quantity research on qunke1 well, cao 1 well, cao 2 well, cao 3...
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