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1.
Mesowear and microwear on enamel from 763 teeth of middle and late Pleistocene ungulates were analysed to infer the potential of dental wear analysis of faunal remains as a paleoenvironmental and paleoclimatic proxy in relation to climatic changes and diversity of vegetation available in the environment. Fossil localities including levels belonging to two glacial and two interglacial stages were selected in Germany, France, and Spain. At a temporal scale, results indicate that the dietary diversity in ungulates is higher during interglacial phases (MIS 5 and 3) than during pleniglacial phases (MIS 8 and 4). Dietary diversity is concluded to be related to climate-driven vegetation changes which during interglacials lead to increased variety of potential food items available to ungulates. At the geographical scale, during interglacials, changes in diet composition are evident along geographical gradients. The corresponding dietary gradients are proposed to be related to climate and vegetation gradients reflecting more arid climates in the Mediterranean area compared to North-Western Europe. Species consistently represented at all localities investigated are Cervus elaphus (Cervidae, Artiodactyla) and Equus ferus (Equidae, Perissodactyla). C. elaphus populations are found to consistently have less abrasive diets than E. ferus populations but dietary traits of both species varied largely, revealing a significant plasticity in the feeding adaptation of both species. Those traits are concluded to be related to differences in vegetation structure at each locality and complement the evidence that ungulates have broader dietary habits than what is usually assumed.  相似文献   

2.
Three to seven oriented paleomagnetic samples were collected from 16 sites in the Nelson Bay and Bridgewater formations at Portland, Victoria, which contains the recently discovered Nelson Bay local fauna (L.F.). The entire section has reversed polarity. These results, along with Globorotalia truncatulinoides within the section, and the presence of underlying middle Pliocene-dated basalts, indicate that the Portland section, and the included Nelson Bay L.F., was deposited within the late Matuyama Chron between 1.66 and 0.73 myr ago. This represents the first well-documented pre-14C Pleistocene mammalian fauna in Australia calibrated in direct stratigraphic context with absolute dating methods. In addition, the reversed polarity for the Bridgewater Formation confirms the previous hypothesis that the depositional history of this beach-sand deposit is time-transgressive across the Brunhes-Matuyama boundary.  相似文献   

3.
Aminostratigraphic data were obtained for Mulinia lateralis samples from closely spaced drillholes on the Cape Lookout, North Carolina barrier islands. Two major aminozones are recognized in the subsurface section based upon D-alloisoleucine/L-isoleucine (A/I) values. These major aminozones can each be subdivided into two additional aminozones based upon direct comparisons with Mulinia A/I data from other North Carolina localities. Correlation of the Cape Lookout Mulinia aminostratigraphy with U-series calibrated A/I data in N.C. indicates that the sampled units represent deposition during the middle to late Pleistocene. The four Cape Lookout aminozones may be assigned to late and early stage 5 (or possibly stages 5 and 7), a portion of the interval during stages 17–19, and at least one interglacial in stages 25–31 of the oxygen isotope record based on correlation to calibrated sites and kinetic model extrapolation.

The aminostratigraphic data obtained from the Cape Lookout barrier islands and nearby areas indicate that there are significant differences in the extent of preservation of the Pleistocene sedimentary record to the southwest of Cape Lookout compared with that to the north-northeast. All four of the recognized Cape Lookout aminozones are present in the subsurface section to the north-northeast of Cape Lookout. In contrast, the two late Pleistocene aminozones are almost completely absent in the subsurface of the barrier islands, and in Onslow Bay, to the southwest of Cape Lookout. These aminostratigraphic interpretations are consistent with the incomplete stratigraphic record recognized by previous investigators for the Cape Lookout-Onslow Bay area. The calibrated kinetic model age estimates for the Cape Lookout aminostratigraphic data now permit quantification of these stratigraphic gaps. The detailed aminostratigraphic results from Cape Lookout also have significant consequences for regional aminostratigraphic correlations on the Atlantic Coastal Plain, and provide valuable information with which to test contrasting models proposed for regional correlation within the context of the preserved stratigraphic record.  相似文献   


4.
A research programme has been set up at Higueral de Valleja Cave in southern Spain to investigate the late survival and eventual extinction of the southern Iberian Neanderthals and the arrival of modern humans. Of key interest in the first phase of research was to understand the depositional environment in the entrance chamber of the cave and to establish whether palaeoenvironmental and dating samples could be retrieved from the Middle and Upper Palaeolithic sequences. The outcome is a series of OSL, TL and radiocarbon dates showing that the cave was occupied by Neanderthal populations in Marine Isotope Stage (MIS) 3, if not earlier, and by modern human Solutrean populations during the last glacial maximum. Cave sediments provisionally indicate that the lower Middle Palaeolithic sequence (X–VIII) formed in warm and humid environments and the upper sequence (VIII–V) formed when the climate was cooler and drier. The presence of long grass phytoliths and of the small mammals Microtus duodecimcostatus, Microtus brecciensis and Apodemus sylvaticus in the upper sequence indicates that a range of habitat types persisted near the cave including grassland, scrubby vegetation, patchy tree cover and ponds. This raises the possibility that environmental factors were key factors in the late survival of Neanderthal populations at the cave.  相似文献   

5.
The dating of the Stone Age sequence in southern Africa has been considerably revised over the last decade, and one of the anomalies which has resulted is that the Middle Stone Age, now dated to beyond 30,000 B.P., does not immediately precede the Later Stone Age sensu stricto. The excavation and analysis of occupation horizons dating between the most recent Middle Stone Age assemblages and the Holocene is therefore of particular interest. Nelson Bay Cave, situated on the southern coast of South Africa, contains deposits which partly fill the “gap” between the Middle and Later Stone Ages, and the occupation horizons dating between about 18,000 and 5000 years ago are described in this paper. Changes in the habitat in the vicinity of the site caused by sea-level and vegetation changes coincident with the amelioration of temperatures at the end of the Pleistocene are clearly marked in the faunal remains at the site. Largely correlated with the faunal changes (which includes the introduction of marine resources to the cave at about 12,000 B.P.) are changes in the stone artifact assemblages. Three industries are recognized in the sequence: the Robberg, characterized by microbladelets produced from bladelet cores and a few small scrapers and backed tools; the Albany, characterized by large scrapers and an absence of backed tools; and the Wilton, characterized by a variety of Formal Tools including relatively large numbers of small scrapers and backed tools. These changes in artifact-manufacturing traditions are interpreted as signaling adjustments to changing environmental conditions. An explanation for these adjustments is not sought in a simple cause-and-effect relationship between the environment and the cultural response; artifact changes are seen instead as the result of a twofold process, with the environment acting as an external stimulus to change, and the direction of the artifact change governed by the selection of a range of possibilities offered by the technology of the Later Stone Age sensu lato that was widespread in subequatorial Africa during the last 20,000 years.  相似文献   

6.
True 'periglacial' forms and deposits of late (and middle) Pleistocene age can be recognized in the Drakensberg and the adjacent parts of the Cape Province in the latitudinal zone 28° 30'-31°20' S; lower limits in the eastern Cape and Natal appear to lie near 1500–1800 m, rising from southwest to northeast, and at 2600 m in Lesotho. Significant nivation in the Drakensberg is also indicated, but at higher elevations. Alleged 'periglacial' phenomena in Rhodesia, the Transvaal, the Cape Folded Ranges and their coastal margin are not acceptable as such and include no evidence for cryonival or geliflual proceses. Nonetheless, there is bonafide evidence for several phases of accelerated Pleistocene frost-weathering, including sections of the Cape Coast that experience next to no frost today and would require a winter temperature depression of at least 10° C. It cannot be disputed that southern Africa has experienced cold, glacial-age climates, but there is a serious problem about many of the geomorphological observations or their interpretation.  相似文献   

7.
晚更新世以来渤海南部莱州湾发生了3次重要海侵-海退事件及沉积演化过程,渤海南部多源河流三角洲对莱州湾沉积环境改变作用明显。本文选择莱州湾剖面进行沉积地层对比,结合调查资料和测试数据,初步建立莱州湾沉积地层格架,分析晚更新世以来莱州湾沉积演化过程。研究发现,渤海南部中小河流与黄河泥沙为莱州湾沉积物的共同物质来源,二者在不同阶段分别对莱州湾沉积演化起主导作用。提出本区沉积地层具有分期性、分段性和相关性规律。在124.6~72.0 ka B.P.,60.0~24.4 ka B.P.和10.2~4.0 ka B.P.出现过3次暖湿期,分别对应沧州海侵、献县海侵和黄骅海侵,主要发育滨浅海相沉积,向南退积为三角洲/潮坪—河流沉积;由陆向海,短源河流沉积贡献降低,黄河沉积贡献增加。在72.0~60.0 ka B.P.和24.4~10.2 ka B.P.出现2次冷干期,分别对应玉木早冰期和玉木晚冰期,河流相发育,三角洲进积。受海陆交互作用影响,晚更新世以来渤海南部莱州湾大致经历了浅海相—三角洲—潮坪—浅海相—三角洲—陆相的沉积演化。  相似文献   

8.
Rantis Cave is a recently discovered filled cave in central Israel, displaying a rich faunal accumulation of micromammals, ungulates and carnivores. U–Th dating assigns the beginning of accumulation to ca. 140 ka. The accumulation is culturally assigned to the late half of the Middle Paleolithic (MP) period. Single‐grain optically stimulated luminescence measurements attest to a complex sedimentological history. We present the cross‐disciplinary results of taphonomic and geomorphological analyses, which point to the cave serving as a natural pitfall trap for the large fauna, with little human or carnivore activity. The fauna is dominated by Dama among the ungulates and by Microtus among the micromammals. These data in conjunction with ungulate tooth mesowear analysis suggest a xeric Mediterranean environment on the eastern margin of the southern Levantine foothills. The relative taxonomic abundance of ungulate taxa shows some differences from anthropogenic MP sites, possibly reflecting the prey choice patterns of MP hunters. Overall, the natural accumulation scenario for Rantis Cave provides a rare paleoenvironmental and paleoeconomic reference to the rich anthropogenic MP faunas of the Southern Levant, enabling the reconstruction of a rich and diverse environmental setting for this important human dispersal route. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

9.
The NW—SE trending southern California coastline between the Palos Verdes Peninsula and San Diego roughly parallels the southern part and off-shore extension of the dominantly right-lateral, strike-slip, Newport—Inglewood fault zone. Emergent marine terraces between Newport Bay and San Diego record general uplift and gentle warping on the northeast side of the fault zone throughout Pleistocene time. Marine terraces on Soledad Mt. and Point Loma record local differential uplift (maximum 0.17 m/ka) during middle to late Pleistocene time on the southwest side of the fault (Rose Canyon fault) near San Diego.The broad Linda Vista Mesa (elev. 70–120 m) in the central part of coastal San Diego County, previously thought to be a single, relatively undeformed marine terrace of Plio—Pleistocene age, is a series of marine terraces and associated beach ridges most likely formed during sea-level highstands throughout Pleistocene time. The elevations of the terraces in this sequence gradually increase northwestward to the vicinity of San Onofre, indicating minor differential uplift along the central and northern San Diego coast during Pleistocene time. The highest, oldest terraces in the sequence are obliterated by erosional dissection to the northwest where uplift is greatest.Broad, closely spaced (vertically) terraces with extensive beach ridges were the dominant Pleistocene coastal landforms in central San Diego County where the coastal slope is less than 1% and uplift is lowest. The beach ridges die out to the northwest as the broad low terraces grade laterally into narrower, higher, and more widely spaced (vertically) terraces on the high bluffs above San Onofre where the coastal slope is 20–30% and uplift is greatest. At San Onofre the terraces slope progressively more steeply toward the ocean with increasing elevation, indicating continuous southwest tilt accompanying uplift from middle to late Pleistocene time. This southwest tilt is also recorded in the asymmetrical valleys of major local streams where strath terraces occur only on the northeast side of NW—SE-trending valley segments.The deformational pattern (progressively greater uplift to the northwest with slight southwest tilt) recorded in the marine and strath terraces of central and northern coastal San Diego County conforms well with the historic pattern derived by others from geodetic data. It is not known how much of the Santa Ana structural block (between the Newport—Inglewood and the Elsinore fault zones) is affected by this deformational pattern.  相似文献   

10.
Mammoth fossils and other Pleistocene vertebrates from the Upper Missouri Basin, in the northern Plains and Rocky Mountains of the western interior of North America, have been dated to the late Pleistocene and are associated with Wisconsinan deposits. Mammoth remains have also been found in older stratigraphic contexts. For example, Mammuthus columbi and other fossils from the Doeden Locality are in pre-Wisconsinan terrace gravels along the Yellowstone River; the deposits are likely Illinoian or Sangamonian. Faunas that appear to be associated with the Wisconsinan interstadial, before the Last Glacial Maximum, are found in intermountain valleys and mountain settings (the Merrell Locality, Blacktail Cave, Natural Trap Cave) and on the Plains in both glaciated and unglaciated regions (Box Creek, Wibaux gravel pit). Localities containing faunas dated to the time interval from about the Last Glacial Maximum to the end of the Younger Dryas chronozone (late Wisconsinan) include the youngest fossil-bearing strata at Merrell, Blacktail Cave, Natural Trap Cave; deposits at Sheep Rock Spring, Indian Creek, MacHaffie, False Cougar Cave, Shield Trap Cave; and mammoths found at Sun River, Glendive, Colby, and the Deer Creek drainage.  相似文献   

11.
《China Geology》2019,2(1):16-25
There are three transgression-regression events and evolutions of the sedimentary environment by sea level changes since the Pleistocene in the southern section of the Bohai Sea, China. It is obvious that a multi-source fluvial delta sedimentary system may be more dominant in a sedimentary environment. Based on previous research and survey or historical data, we carried out studies on the division of sedimentary units, sedimentary facies analysis and strata division and comparison, which aim to establish the sedimentary stratigraph of Laizhou Bay. We focus on the sedimentary procession of the Laizhou Bay since the early Late Pleistocene. It can be divided into two glacial periods and three interglacial periods, corresponding to two regression and three transgression events in Laizhou Bay since Late Pleistocene. In 124.6–72.0 ka BP, 60.0–24.4 ka BP and 10.2–4.0 ka BP, three times warm-wet periods occurred, respectively corresponding to the Cangzhou transgression, Xianxian transgression, and Huanghua transgression. In 72.0–60.0 ka BP and 24.4–10.2 ka BP, two dry and cold periods, it was the continental sedimentary environment, corresponding to Wurm early glacier and Wurm late glacier. The results show: (1) Sediments have the characteristics of phase and stage under the terrestrial input of the Yellow River and middle-small rivers in the southern section of the Bohai Sea. (2) PI moved towards coastal in Cangzhou transgression strata in early Late Pleistocene. PI moved northward from land in Xianxian transgression strata in the late Pleistocene. PI moved further north in the Huanghua transgression strata in Holocene. (3) During the regressive period, the land source input increased and the estuarine or lagoon sedimentation developed, which manifested as progradational superposition. (4) During the transgressive period, it mainly developed shallow coastal sediment and transitionally formed regressive deposition to the south in delta/tidal flat deposition.©2019 China Geology Editorial Office.  相似文献   

12.
文章报告了在广西崇左生态公园三合大洞中新发现的巨猿牙齿化石,这些新化石材料为研究巨猿演化及华南地区更新世动物群时代演化及环境变迁有着重要意义。三合大洞共出土巨猿牙齿56枚,除上犬齿,其他上、下颌牙齿种类齐全;从牙齿发育及磨损情况判断,这些材料代表了婴幼年、青少年、青壮年、中年及老年各年龄阶段的至少5个个体。测量了牙齿大小,并与其他的巨猿化石点的材料进行对比,认为三合大洞的巨猿牙齿与武鸣、巴马的巨猿有可比性。在此基础上,结合动物群组合特征及时代意义,探讨巨猿的牙齿大小时代演化趋势,同时提出存在的问题。  相似文献   

13.
From 1985 to 1987, four new localities with abundant fossil mammals were dis-covered by Cao, Tian and others in the Zhoukoudian (Choukoutien) area, Beijing. They are theEast, West, Shangdian and Donglingzi caves. The East Cave fauna consists of 28 speices ofmammals and its age is middle Early Pleistocene. The East Cave assemblage shows that a tem-perature-falling event took place at around 1.20 Ma B.P. at Zhoukoudian. Sixteen species ofmammals were collected from the West Cave, which are mainly forms of late Early Pleistoceneage. The West Cave fauna represents a transitional fauna from the East Cave fauna (dry-cold)to the fauna (warm) at locality 9. The Shangdian Cave fauna is composed of four forms, beingMiddle Pleistocene in age. The Donglingzi Cave fauna contains 21 Late Pleistocene forms. Inthe cave two fossil horizons may be distinguished. The age of the lower horizon is early LatePleistocene, which is equivalent to that of the New Cave fauna; while the fauna of the upper ho-rizon may be correlated with the Upper Cave fauna.  相似文献   

14.
根据对青藏高原沱沱河流域的雅西错湖湖相沉积、西金鸟兰湖岸边的湖相沉积和昆仑河河流相沉积记录的晚更新世以来的孢粉资料的对比分析，该地区2种标志性花粉蒿属（Artemisia）、藜科（Chenopodiaceae）的百分含量表现出明显的负相关性，从南向北、从老到新，孢粉的种类、乔木花粉的数量逐渐减少，禾本科（Gramineae）花粉百分含量逐渐降低，蕨类孢子数量少；在研究区南部晚更新世早期出现了以白刺属（Nitraria）为代表的干旱灌丛草原植被，在研究区3-1万年之间出现了以蒿属、禾本科为代表的干偏湿的草原植被；总体上，根据晚更新世的孢粉恢复的古环境，南部地区比北部地区偏湿。这一特征对恢复青藏高原晚更新世的古环境具有重要的参考意义。  相似文献   

15.
In late Pleistocene time Lake Dieri (ancestral ‘Greater Lake Eyre') was permanently filled during a wet climatic phase. Towards the close of Pleistocene time the watertable fell, Lake Dieri dried up, and its sediments deflated. Later the watertable rose, establishing ephemeral Lake Eyre in the deflated area, and Holocene sedimentation commenced. At about this time Lake Eyre tilted to the south and three sedimentary environments developed: (1) a saline playa environment without saltcrusts in the northern end of the lake, where water drains away before wholly evaporating; (2) a terminal salina environment in the south end, where evaporation of brines leaves saltcrusts overlying gypseous sediments; and (3) a saline flocculation environment between the playa and salina environments, where sediments are deposited by flocculation when muddy floodwater from the north meets highly saline water of the southern salina.

In the northern playa environment, sedimentation is limited to the top of the capillary fringe above the watertable, below which sediments remain moist and protected from aeolian erosion, but above which they dry and blow out of the lake. In the southern salina environment sedimentation has not kept pace with the Holocene rise in watertable. If and when it does reach such a level, downward leaching of salt and deflation of exposed sediments is likely to occur. In the flocculation environment new deposits of clay are added but kept permanently wet by rising groundwater. When flocculated sediment builds too high, its excess is transferrred by surface water into the salina deposits to the south.  相似文献   

16.
Climatic instability during the late Pleistocene has been reflected in the pattern of groundwater recharge. This report summarizes palaeoclimate knowledge during the late Weichselian in Europe. During this period the majority of northern Europe was covered by thick ice sheets and permafrost, preventing aquifers from recharging. In contrast, southern Europe was generally free of these palaeoclimatic features. Palaeoclimatic information has been combined with isotope data to better understand the palaeorecharge conditions and recharge timing across the European continent. The 18O and 2H relationship shows latitudinal plus climatic influences. Radiocarbon data show that while southern European aquifers have generally been recharged continuously during the last 40,000 years, northern European aquifers typically show a recharge gap during the Last Glacial Maximum. Areas that underwent continuous recharge during the entire late Pleistocene period can also be distinguished from areas where recharge to aquifers was prevented during the Last Glacial Maximum. Finally, several examples are presented of melt-water recharge or subglacial recharge. The identification of such diversity in the groundwater palaeorecharge in Europe is of great importance for modellers developing management schemes for groundwater resources.  相似文献   

17.
This contribution discusses recent paleoanthropological findings from Huanglong Cave, a Late Pleistocene human fossil site from Yunxi County, Hubei Province, China. Three excavations in the Huanglong Cave from 2004 to 2006 yielded seven human teeth, some stone and bone tools, possible burnt sediment and other evidence possibly related to hominin activities. Based on the presence of extinct faunas (20% of total taxa identified), the deposits dated to the Late Pleistocene. Electron spin resonance (ESR) and uranium-series (U-series) dating analyses on associated teeth and speleothems have resulted in divergent chronometric ages (ESR: 44–34 ka; U-series: 103–79 ka). Analysis indicates: (1) most of the morphological and metric features of the human teeth from Huanglong Cave fall within the range of variation of modern Chinese, but a few characters may still link them to more archaic hominins; (2) some activity-induced abrasion and other tooth use-marks were identified, including pronounced tooth chipping and interproximal grooves on the anterior teeth; (3) the sample of blackened deposit has a high carbon content (over 70%), experienced high temperatures, and likely was of cultural origin and not natural; (4) the mammal fossils represent the “Ailuropoda-Stegodon” faunal unit which lived in southern China throughout the Pleistocene. Synthesizing all of these findings, especially the human teeth that display modern human characteristics, Huanglong Cave will offer some new insights into various issues currently being debated in Late Pleistocene human evolutionary research.  相似文献   

18.
Biostratinomic analysis (processes acting between death and burial) of Lateglacial mammal bone assemblages from three caves in northern England demonstrates the value of re‐examining archived assemblages. With AMS radiocarbon dating of key specimens, these assemblages shed light on the ecology of a region at the northern limit of Lateglacial human activity in Britain. During the Lateglacial Interstadial bears, wolves and humans expanded into the region, bears by around 12 500 14C yr BP, and the earliest evidence for human presence is around 12 300 14C yr BP. At Victoria Cave, wolf activity included predation and scavenging of large ungulates and scavenging bear carcasses apparently resulting from hibernation deaths. The scavenging of bear carcasses is possibly confined to the first part of the Lateglacial Interstadial, whereas evidence for wolf scavenging large ungulates increases later in the Interstadial, after about 11 800 14C yr BP, perhaps reflecting changes in the productivity of the Lateglacial ecosystem, and in human subsistence patterns. The assemblage from Sewell's Cave is wolf den debris from the very end of the Lateglacial Interstadial around 10 800 14C yr BP, whilst that from Kinsey Cave is dominated by large‐bodied carnivores, and is argued to have a quite different taphonomic history. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

19.
Spawning densities, spawning indices, egg densities, size distributions, and movement patterns of horseshoe crabs (Limulus polyphemus) were quantified for four coastal embayments (Monomoy National Wildlife Refuge, Pleasant Bay, Nauset Estuary, and Cape Cod Bay) on Cape Cod, Massachusetts from 2000 to 2002. Spawning activity was highest from mid May through mid June, but densities varied throughout the Cape Cod region. Average spawning densities (male and female crabs combined), measured using 25-m2 quadrats, were lower than 1 crab 25 m?2, although certain locations had consistently higher densities averaging 2 to 3 crabs 25 m?2 with individual survey densities recorded as high as 17 crabs 25 m?2. Spawning densities during night surveys were either similar or slightly higher than day surveys, except at a few sites within Pleasant Bay. Spawning indices were considerably lower ranging from 0 to 1.3 females 25 m?2 throughout the Cape Cod region. Spawning sex ratios varied from 1∶1.6 to 1∶3.1 (females:males) throughout the region, except within Pleasant Bay where highly male skewed ratios were observed (e.g., 1∶5.8, 3-yr average). Egg densities were low overall (<1 egg cm?2) throughout Cape Cod and egg densities tended to be higher in deeper sediments (5–20 cm deep) compared to shallow sediments (0–5 cm deep) at most locations. Over 7,800 horseshoe crabs were tagged on Cape Cod from 2000 to 2002. Average size and size frequency distributions of tagged crabs varied among regions. Larger individuals were observed at Monomoy National Wildlife Refuge while the smallest individuals were from Cape Cod Bay. We documented an overall recapture rate of 6.7% and our tag-recapture data indicated that 62% of crabs were recaptured at the original tagging location and 70% of recaptures traveled less than 2 km from the original tagging location, providing evidence for localized populations on Cape Cod. We have observed that horseshoe crabs differ among embayments within a regional area, suggesting the potential need for management plans specific to embayments or subregions depending on the characteristics of a population.  相似文献   

20.
Materials of bottom sampling and drilling on Ebelyakh Bay, the Cape Svyatoi Nos area, and southern part of the Dmitry Laptev Strait by researchers from VNIIOkeangeologiya during the past 60 years and data on the geological setting of the Chokhchur–Chokurdakh zone (Ebelyakh Bay included) were also examined. The geology and lithology of Cenozoic sediments in the water area of the bay and adjacent land were scrutinized to elucidate mineral resources in the Earth’s interior in the study area. Analysis of the Upper Jurassic–Holocene summary section shows that terrigenous material was derived from (i) coastal zones composed of granitoid or contact metamorphic rocks, (ii) Quaternary friable sediments of marine terraces and beaches, (iii) submarine rises, and (iv) river discharge. It is shown that cassiterite is associated with the Pliocene–lower Pleistocene Serkino horizon and Holocene sediments. New promising cassiterite areas have been revealed. The results suggest that prospecting for tin placers should be continued at Ebelyakh Bay.  相似文献   

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