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1.
利用地层序列中火山碎屑岩、凝灰岩及其火山岩锆石U-Pb同位素测年,对晋东北地区侏罗纪地层时代进行了重新厘定。取得了以下主要认识:(1)确认宁武—静乐盆地下侏罗统永定庄组的存在;(2)宁武—静乐盆地天池河组可以与鄂尔多斯盆地安定组相对比,归属于中侏罗统;(3)浑源盆地髫髻山组应归属于中侏罗统上部,该套火山岩地层在整个燕—辽地区具有穿时性;(4)广灵盆地中侏罗统窑坡组底部厚层砾岩的沉积时代可能与燕山造山带的南大岭组相当,应该属于早侏罗世至中侏罗世早期构造运动的产物。通过地层序列的重新厘定,确认了159.0~(152.77±0.63)Ma区域角度不整合的存在,该期构造运动可能与侏罗纪东亚大陆多向汇聚产生的远程效应有关。 相似文献
2.
燕山期造山事件广泛影响东亚地区的构造演化,其启动时间与构造变形样式还存在较多的争议。侏罗纪宁武-静乐盆地位于华北克拉通中北部吕梁山地区,处在华北平原盆地与鄂尔多斯盆地之间,是吕梁山-太行山内部NE-SW走向的向斜盆地,为燕山期陆内造山作用的研究提供了例证。本文通过构造变形分析、平衡剖面恢复与生长地层碎屑锆石年代学分析,厘定了侏罗纪宁武-静乐盆地构造变形样式、原型盆地性质与生长地层开始形成的时间,探讨了燕山期构造变形的盆山耦合效应。其中,盆地北段西侧发育断展褶皱与对冲构造;盆地中段西侧发育断展褶皱与背冲构造,中段东侧发育断展褶皱;盆地南段西侧发育断展褶皱与叠瓦状逆冲构造。中侏罗统云岗组(J_2y)与上侏罗统天池河组(J_3t)为生长地层,记录了侏罗纪宁武-静乐盆地的生长与变形过程,反映了该地区燕山期造山事件的作用过程。前生长地层构造变形反映的侏罗纪宁武-静乐盆地地壳缩短率在盆地中段为26.2%,南段为58.6%。碎屑锆石定年研究限定了该地区燕山造山作用的启动时间为～168 Ma。由此认为,华北克拉通中北部是中生代燕山期造山作用最显著的地区之一,燕山期造山事件是纵贯华北吕梁山-太行山造山带崛起的主因。 相似文献
3.
侏罗纪/白垩纪之交是中国中东部乃至东亚地区构造活动的重要时期,发生了构造变形、岩浆-成矿、气候环境突变等一系列重大的构造事件,被称为"燕山运动",但对于其启动时限的认识却一直存在着争议。本文以晋东北侏罗纪盆地为研究对象,在早中侏罗世沉积序列划分和重矿物组合特征变化研究的基础上,结合重点层位火山岩夹层锆石U-Pb同位素测年,详细刻画了这期构造事件启动的具体时限。研究认为,中侏罗统云岗组(J2yg)底部砾岩沉积时期,沉积序列由早期的湖进序列向湖退序列转换,碎屑岩的成分由早期的以石英、长石为主过渡为以长石、岩屑为主,重矿物组合由早期的以锆石为主过渡为以石榴子石为主,预示着侏罗纪构造活动进入了启动阶段。通过下侏罗统永定庄组(J1y)火山碎屑岩的年龄(179.2±0.79)Ma和中侏罗统云岗组(J2yg)顶部凝灰质碳酸盐岩年龄(160.6±0.55)Ma的制约,推测中侏罗统云岗组(J2yg)底部砾岩沉积时间大约为168 Ma,这个时间代表了侏罗纪构造活动(燕山运动)的起始时限。该成果在沉积学方面为燕山运动的起始时限提供了新的制约。 相似文献
4.
利用凝灰岩夹层及安山岩的锆石U-Pb同位素测年,对云岗盆地晚中生代地层充填序列的关键时限进行了限定。结合地层接触关系、安山岩的地球化学特征,分析了重点地质界面的构造意义。取得了以下主要认识:(1)早中侏罗世,盆地为一套湖进序列的连续沉积,以大同组含煤地层为代表,暗示着区域拉张的构造背景;(2)盆地整体缺失了晚侏罗世(160.4±1.1)Ma至早白垩世(130.1±0.7)Ma的沉积地层,其发生的动力学背景可能与古太平洋、西伯利亚、特提斯同时向东亚大陆汇聚产生的远程效应有关;(3)旧高山安山岩形成于早白垩世(130.1±0.7)Ma大陆板内裂谷的构造背景,与华北克拉通破坏的动力学背景紧密相关。研究成果对旧高山安山岩时代归属提出了新的认识,并不归属于上侏罗统髫髻山组,而相当于下白垩统张家口组。 相似文献
5.
柴达木盆地北缘沉积凝灰质岩层段的地层时代 总被引：2，自引：0，他引：2
柴达木盆地北缘深部沉积凝灰质岩层段的地层归属存在2种观点,下侏罗统和石炭系。本文通过岩石薄片、微量元素、孢粉组合以及海相化石碎片等多种资料的综合分析,认为沉积凝灰质岩层段与其上的下侏罗统之间岩性、电性出现突变的主要原因是沉积时火山事件以及晚期方解石脉充填造成的,并不能代表下伏的老地层;沉积凝灰质岩层段的海相化石碎片为搬运再沉积的结果,没有地层指示意义;孢粉组合能反映沉积凝灰质岩层段沉积的地质年代,据此确认沉积凝灰质岩层段为下侏罗统湖西山组二段。 相似文献
6.
侏罗纪地层为中国内陆沉积盆地油气富集的主要时期地层。通过在前人的研究基础上大量收集露头资料以野外剖面实测为重点,对山西不同地区侏罗纪地层不同组进行岩性、岩相、沉积特点及环境等分析,描述出不同地区各个组的沉积特点。划定山西侏罗纪地层划分为早侏罗永定庄组,中侏罗大同组、云岗组、天池河组,缺失晚侏罗地层;对沉积相进行系统分析,确定山西侏罗纪地层与鄂尔多斯盆地侏罗纪地层具有等时性,且空间上为鄂尔多斯盆地侏罗纪地层的边缘沉积,油气勘探前景不乐观。 相似文献
7.
中-新元古代四堡造山运动将扬子地块和华夏地块拼合成一个完整的华南板块。四堡造山运动结束后,位于华南板块东北部的浙北分区沉积了一套新元古代骆家门组地层,其底部以砾岩和砂质砾岩为特色,且以角度不整合直接覆盖于四堡造山单元双溪坞群之上。骆家门组地层的精确沉积时限对了解四堡造山结束后华南板块新一轮沉积盆地的形成和发展具有重要意义。本文对采自浙北富阳地区骆家门组底和顶部的两件沉凝灰岩样品进行SIMS锆石U-Pb定年工作,并据此分析骆家门组的起始沉积时间略早于845Ma,终止沉积时间略晚于830Ma。综合前人研究,我们认为浙北分区保存了华南板块新一轮沉积盆地(南华盆地)的早期沉积活动信息,骆家门组的初始沉积时限指示了南华盆地的开启时间略早于845Ma。 相似文献
8.
鄂尔多斯盆地中—晚侏罗世构造事件的沉积响应 总被引：3，自引：0，他引：3
中—晚侏罗世是东亚大地构造发展的重要转折时期,鄂尔多斯盆地周缘构造带记录了强烈的陆内多向挤压变形,其发生的动力学背景与古太平洋、西伯利亚、特提斯同时向东亚大陆汇聚产生的远程效应有关。鄂尔多斯盆地侏罗纪沉积记录了该期构造事件的发生、发展过程:(1)自早侏罗世富县期至晚侏罗世芬芳河期,鄂尔多斯盆地岩相古地理演化经历了河流-冲积扇、湖泊-沼泽、河流-三角洲和冲积扇,中侏罗统直罗组底部砾岩发育时期为湖进序列向湖退序列转换的关键时期;(2)Qm-F-Lt图解中,中侏罗统延安组砂岩投点落入了稳定克拉通范围,中侏罗统直罗组和安定组的投点落入了石英再造山旋回范围内,预示着中侏罗世直罗期,鄂尔多斯盆地周缘构造活动性迅速增强;(3)中侏罗统安定组内部发育了一套全区可以稳定对比的泥晶碳酸盐岩,生物化石发育,该套泥晶碳酸盐岩上下地层的颜色由早期的灰绿色突变为紫红色,古盐度突然升高,预示着古气候环境突变,构造活动更为强烈;(4)根据盆地内热流体的记录及相邻区碎屑锆石年龄谱特征,中晚侏罗世构造事件发生的起始、强烈活动时限分别为168.0 Ma和161.0 Ma。 相似文献
9.
大巴山构造带东段秭归盆地侏罗纪沉积充填过程及其构造演化 总被引：4，自引：0，他引：4
位于大巴山构造带东段秭归盆地较为完整地保存了侏罗纪地层,其沉积和构造演化过程可划分两个不同阶段,即早侏罗世受西北缘断裂走滑控制的伸展阶段和中、晚侏罗世受东部黄陵地区抬升挤压消亡的阶段。下侏罗统香溪组底部砾岩表明侏罗纪盆地开始形成。盆地北缘的砾岩较厚,主要形成于冲积扇和辫状河体系,并在其砾石中发现化石砾石,显示距离物源区较近。盆地东南部和南部砾岩较薄,形成于曲流河沉积环境。古水流和碎屑物源分析表明,盆地早期沉积物主要来自于盆地北部神农架地区。中侏罗统泄滩组和陈家湾组以湖泊相沉积为主。上沙溪庙组和下沙溪庙组为较成熟的曲流河沉积,沉积砾岩中无灰岩和燧石,几乎全部为泥岩砾石。上侏罗统遂宁组和蓬莱镇组虽然也为曲流河沉积,但其河床砂岩底部再次出现了灰岩、燧石等砾石。另外,中侏罗统上部和上侏罗统古水流方向为自东向西,指示物源区变为盆地东部的黄陵背斜地区。盆地的沉积充填特征和盆地西北缘具左行走滑运动的高桥断裂,以及北部南倾的多条逆断层表明断层对盆地形成的主控作用。黄陵背斜地区后期的不断抬升对秭归盆地有重大影响,持续的抬升可能导致盆地消亡。秭归盆地的沉积充填和演化过程,是对大巴山构造带东段“燕山运动”的响应。 相似文献
10.
中生代是济源盆地形成并发展的重要时期。秦岭造山带在晚三叠世造山以及太行山在中侏罗世隆升对济源盆地的沉积格局产生了显著影响,这段时间,盆地始终处在一个盆山相互作用的阶段,将盆地与造山带的构造演化联系起来,有利于更好的认识这一构造沉积响应过程。本文通过对济源盆地中生代地层、沉积及其充填特征的研究,将盆地中生界划分为4个构造层序:TS1、TS2、TS3、TS4,其中TS1充填了下三叠统刘家沟组、和尚沟组和中三叠统二马营组、油房庄组,它是在扬子、秦岭及华北板块汇聚的背景下形成的内陆克拉通型层序。TS2、TS3分别充填了上三叠统椿树腰组、谭庄组和下侏罗统鞍腰组(义马组)、中侏罗统杨树庄组,它们都具有前陆盆地型充填特征,分别响应的是秦岭造山带造山作用沿洛南—栾川断裂以及三门峡—鲁山—舞阳断裂发生的逆冲推覆作用。TS4充填的是中侏罗统马凹组,受太行山隆升作用的影响,形成了厚层的磨拉石堆积。在此基础上,可将济源盆地盆山系统演化归为3个阶段:早—中三叠世大陆基底隆升与内陆克拉通型盆地,晚三叠世—中侏罗世早期秦岭造山与前陆盆地,中侏罗世晚期太行山隆升与山间盆地。显然,济源盆地响应了秦岭造山及太行山隆升,秦岭造山带晚三叠世造山表现为两次逆冲推覆作用,而太行山主体隆升应在中侏罗世晚期,标志着华北克拉通破坏进入高峰期。 相似文献
11.
《International Geology Review》2012,54(3):288-312
A series of significant geological changes indicated by deformation, magmatic–metallogenic systems, and the climate and environment occurred in East Asia during Late Jurassic to Early Cretaceous time, but the timing and development of the ‘Yanshan movement’ on the north margin of the North China Craton has not been well-established. Based on the evidence of tectonic deformation and magmatic activity, previous studies resulted in two views of the beginning of the Yanshan movement: Early Jurassic vs. late Middle Jurassic. In this work, the timing of the initial Yanshan movement was investigated by examining the Jurassic Chenjiabangou section in the Ningwu–Jingle basin overlying the north-central part of the North China Craton. The timing of the initial Yanshan movement was constrained by restoration of stream flow directions, determination of boundaries of sedimentary cycles, identification of heavy mineral assemblages in clastic rocks, quantification of changes in chemical compositions, and zircon U–Pb isotope dating. The results indicate that the basal conglomerates of the Middle Jurassic Yungang Formation (Bathonian) mark the beginning of the Yanshan movements. Evidence supporting this conclusion includes the following. (1) The switch from transgressive lacustrine deposition to regressive lacustrine deposition in the Yungang Formation sedimentary succession indicates a change from extension to compression, possibly reflecting uplift. (2) Early-stage clastic rocks rich in quartz and feldspar are replaced by feldspar detritus in late-stage clastic rocks; the heavy mineral assemblage dominated by zircon at the early stages changed to garnet-dominated assemblage upsection. Moreover, the concentrations of CaO, MgO, CO2, and Fe2O3 + FeO and the Fe2O3/FeO ratio changed abruptly near the basal conglomerates of the Middle Jurassic Yungang Formation, suggesting increased denudation. (3) Conglomerates at the bottom of the Middle Jurassic Yungang Formation were deposited approximately 168 million years ago, as inferred from the age of zircons in tuffaceous micrite (160.6 ± 0.55 Ma) at the bottom of the Upper Jurassic Tianchihe Formation (Oxfordian) and the age of zircons in pyroclastic rocks (179.2 ± 0.79 Ma) in the Lower Jurassic Yongdingzhuang Formation (Toarcian). These lines of evidence indicate that initial Jurassic Yanshan movement began 168 million years ago during Middle Jurassic time. 相似文献
12.
《International Geology Review》2012,54(12):1528-1556
ABSTRACTThe intra-continental orogeny and tectonic evolution of the Mesozoic Yanshan fold-thrust belt (YFTB) in the northern North China Craton (NCC) have been strongly debated. Here, we focus on the Shangyi basin, located in the centre of the YFTB. An integrated analysis of sedimentary facies, palaeocurrents, clast compositions, and detrital zircon dating of sediments was adopted to determine the palaeogeography, provenance, basin evolution, and intra-continental orogenic process. The Shangyi basin comprises the well-exposed Early–early Middle Jurassic Xiahuayuan Formation and the Longmen Formation, and the Late Jurassic–Early Cretaceous Tuchengzi Formation. Based on the 18 measured sections, five facies associations – including alluvial fan, fluvial, delta, lacustrine, and eolian facies – have been identified and described in detail. The onset of the Shangyi basin was filled with fluvial, deltaic, and lacustrine deposits controlled by the normal fault bounding the northern basin, corresponding to the pre-orogeny. In the Middle Jurassic, the cobble–boulder conglomerates of alluvial fan, as molasse deposits, were compatible with the syn-orogeny of the Yanshan movement, which played a critical role in northern North China and even East Asia. After the depositional break in the Middle–Late Jurassic, the Shangyi basin, controlled by the normal fault present in the north of the basin, re-subsided and quickly expanded southward with thick sedimentation, which is correlative with the post-orogeny. Combined with A-type granites, metamorphic core complexes, mafic dikes, and rift basins of the Late Jurassic–early Early Cretaceous present in the northern NCC and Mongolia, significant extension was widespread in the northern NCC and even in northeast Asia. Moreover, vertical changes of provenance indicate that the Taihang Mountain and the Inner Mongolia palaeo-uplift (IMPU) present at the west and north of the basin, respectively, experienced uplift twice in the Middle–Late Jurassic and Early Cretaceous, resulting in a regional depositional break. 相似文献
13.
本文根据重新理清的辽西凌源牛营子盆地晚三叠世-中侏罗世地层层序及时代,讨论其区域地层对比.晚三叠世晚期的邓杖子组是一套崩滑流为主的碳酸盐角砾,其为区域印支期构造运动的造山记录,与京西、冀北杏石口组、辽西北票羊草沟组(坤头菠罗组)可以对比;早侏罗世水泉沟组与京西、冀北南大岭组、辽西北票兴隆沟组层位相当,且各组火山岩时代基本相同;中侏罗世早期郭家店组底部含煤段与京西上窑坡组、冀北下花园组中部、辽西北票组中上部植物组合面貌一致;中侏罗世中期郭家店组砾岩段是燕山期构造变形主幕的产物,北京西山龙门组、冀北下板城下花园组上部、辽西北票海房沟组都是该期的记录,层位相当;辽西中侏罗世中晚期蓝旗组底部的时代为158±1Ma,与京西、冀北髫髻山组安山岩的同位素年龄总体一致.这说明差异较大的燕山板内造山带三叠纪-中侏罗世盆地的沉积记录显示了相似的演化规律. 相似文献
14.
鄂尔多斯盆地西缘前陆盆地构造-沉积响应 总被引：2，自引：0，他引：2
鄂尔多斯盆地西缘前陆地区在晚三叠世-中侏罗世经历了印支运动和燕山运动早期的影响,西缘整体抬升,西南和西北两个造山带开始显现,古地理为继承性的南湖北河格局,此时秦岭造山带的形成使西南地区由滨海相向湖沼相过渡。晚侏罗世-早白垩世是西缘地区前陆盆地形成时期,燕山中期逆冲推覆作用强烈,该区地层角度不整合发育,沉积记录的响应表现为南北向隆坳相间的前陆盆地格局,有别于前陆盆地形成始于晚三叠世的认识。晚白垩世-新生代是喜山运动的后期改造时期,地层角度不整合发育,沉积响应为平原沼泽相沉积。 相似文献
15.
《International Geology Review》2012,54(3):327-341
The northern Yangtze foreland basin system was formed during the Mesozoic continental collision between the North and South China plates along the Mianlue suture. In response to the later phase of intra-continental thrust deformation, an extensive E–W-trending molasse basin with river, deltaic, and lake deposits was produced in front of the southern Qinling–Dabieshan foreland fold-and-thrust belt during the Early–Middle Jurassic (201–163 Ma). The basin originated during the Early Jurassic (201–174 Ma) and substantially subsided during the Middle Jurassic (174–163 Ma). A gravelly alluvial fan depositional system developed in the lower part of the Baitianba Formation (Lower Jurassic) and progressively evolved into a meandering river fluvial plain and lake systems to the south. The alluvial fan conglomerates responded to the initial uplift of the southern Qinling–Dabieshan foreland fold-and-thrust belt after the oblique collision between the Yangtze and North China plates during the Late Triassic. The Qianfoya Formation (lower Middle Jurassic) mainly developed from shore-shallow lacustrine depositional systems. The Shaximiao Formation (upper Middle Jurassic) predominantly consists of thick-bedded braided river delta successions that serve as the main body of the basin-filling sequences. The upward-coarsening succession of the Shaximiao Formation was controlled by intense thrusting in the southern Qinling–Dabieshan fold-and-thrust belt. Palaeogeographic reconstructions indicated an extensive E–W foredeep depozone along the fold-and-thrust belt during the Middle Jurassic (174–163 Ma) that was nearly 150 km wide. The depozone extended westward to the Longmenshan and further east to the northern middle Yangtze plate. The northern Yangtze foreland basin was almost completely buried or modified by the subsequent differential thrusting of Dabashan and its eastern regions (Late Jurassic to Cenozoic). 相似文献
16.
根据沉积充填与沉积演化分析,昌都盆地中生代为一个叠合型盆地,晚三叠世为一个陆内断陷盆地,经历了断陷期-坳陷期-萎缩期,侏罗纪为一个受东、西两侧造山带挤压而形成的山间坳陷盆地。喜山期,昌都盆地经历了强烈的改造。昌都盆地存在3套烃源岩,即阿堵拉组和夺盖拉组潟湖相泥岩和沼泽相含煤岩系、中侏罗统东大桥组深湖相泥岩和灰岩; 4套储集岩,即甲丕拉组河流相碎屑岩、阿都拉和夺盖拉组滨岸相和三角洲相碎屑岩、波里拉组颗粒灰岩和白云岩。有利油气构造均形成于侏罗纪末,与三叠系的生油阶段基本吻合,可形成较好的油气成藏,其中昌都-察雅香堆为最有利油气远景区。 相似文献
17.
扬子北缘黄陵地区古构造应力场于晚中生代经历发生了重大转变,是扬子板块与华北板块在三叠纪碰撞造山之后陆内构造变形的体现。由黄陵背斜周缘晚中生代盆地充填记录所反映出这一变革的起始时间为中侏罗世晚期。早侏罗世-中侏罗世早期,盆地内沉积了以桐竹园组为代表的河流-湖泊相岩层,由沉积碎屑成分和古水流统计所得出的物源区为北部的秦岭地区,黄陵背斜上部可能也接受了碎屑沉积;中侏罗世晚期-晚侏罗世,沉积中心发生了改变,表现为仅仅在黄陵背斜西侧的秭归盆地内有所保存,沉积环境以曲流河到辫状河流和三角洲为主,物源区则局限于黄陵背斜;早白垩世初期,周坪盆地和宜昌盆地为沉积中心,近缘冲积扇和辫状河流体系占据主体,物源区依然为黄陵地区,两盆地在黄陵背斜南缘可能相连,黄陵背斜上部的原下侏罗统被剥蚀;早白垩世晚期-晚白垩世,远安盆地逐渐发育,盆地西缘为冲积扇-辫状河流体系,中、 东部则以曲流河-湖泊沉积环境为主体,并间有干旱沙漠环境。原型盆地再造结果显示,早侏罗世-中侏罗世早期盆地展布具有近东西向特点,古地貌总体呈现出北部为山脉、 南部为盆地的格局;中侏罗世晚期以来,盆地呈近南北向,黄陵背斜逐渐形成山脉,盆地位于其东西两侧。两期盆地沉积特征反映了扬子北缘古构造应力场由近南北向转变为近东西向的过程。 相似文献
18.
Tianyi Shen Yue Chen Guocan Wang Junliang Ji Yong Wang Pan Zhang Paul Sotiriou Rong Guo Zezhuang Xu 《地学学报》2020,32(2):166-178
Analysing the provenance changes of synorogenic sediments in the Turpan‐Hami basin by detrital zircon geochronology is an efficient tool to examine the uplift and erosion history of the easternmost Tian Shan. We present detrital zircon U‐Pb analysis from nine samples that were collected within marginal lacustrine Middle‐Late Jurassic and aeolian‐fluvial Early Cretaceous strata in the basin. Middle‐Early Jurassic (159–172 Ma) zircons deriving from the southern Junggar dominated the Middle Jurassic sample from the western Turpan‐Hami basin, whereas Permian‐Carboniferous (270–330 Ma) zircons from the Bogda mountains were dominant in the Late Jurassic to Early Cretaceous samples. Devonian‐Silurian (400–420 Ma) and Triassic (235–259 Ma) zircons from the Jueluotage and Harlik mountains constituted the subordinate age groups in the Late Jurassic and Early Cretaceous samples from the eastern basin respectively. These provenance transitions provide evidence for uplift of the Bogda mountains in the Late Jurassic and the Harlik mountains since the Early Cretaceous. 相似文献
19.
大兴安岭北部的漠河盆地广泛发育中生界二十二站组砂岩,其形成时代一直备受争议.首次利用碎屑锆石LA-ICP-MS U-Pb法测年对其形成时代作出较为精确的限定,并结合地球化学特征对其物源区及大地构造背景进行了探讨.研究结果表明,二十二站组砂岩碎屑物磨圆度较低、分选差,表现出源区相对不稳定,快速剥蚀、搬运及沉积的特征.锆石颗粒粗大,具有清晰的震荡环带,Th/U值为0.35～1.07,为典型的岩浆锆石.测年结果显示,90个测点年龄主要分布在3个群落:152～170Ma,峰值年龄约为158Ma,这一年龄区间揭示了二十二站组沉积成岩的下限为晚侏罗世;179～193Ma,峰值年龄约为190Ma;205～214Ma,峰值年龄约为210Ma.3个年龄峰值为蒙古-鄂霍茨克洋演化过程中一系列岩浆活动的地质记录,其中210Ma与190Ma峰值年龄与盆地南缘额尔古纳地块晚三叠世、早侏罗世的岩浆事件相吻合,而158Ma峰值年龄则对应于盆地北缘晚侏罗世的岩浆事件.主、微量元素构造判别图解揭示其物源区具有活动大陆边缘的特征,同时锆石定年数据显示其没有任何前中生代的碎屑物,暗示了该3期岩浆岩均形成于额尔古纳地块北缘的中生代活动大陆边缘环境,并为二十二站组的形成提供了主要碎屑物质.由此说明,二十二站组砂岩形成于晚侏罗世蒙古-鄂霍茨克洋闭合后的造山过程中,漠河盆地南北两侧物源区快速剥蚀、快速搬运与快速沉积的环境. 相似文献