| 词条 | Bahe Formation | |||||||||||
| 释义 |
| name = Bahe Formation | image = | caption = | type = Geological formation | age = Tortonian | period = Tortonian | prilithology = Conglomerate, sandstone | otherlithology = Mudstone, marl | namedfor = | namedby = | region = Shaanxi | country = {{CHN}} | coordinates = {{coord|33.5|N|109.5|E|display=inline,title}} | unitof = | subunits = | underlies = Lantian Formation | overlies = Koujiacun Formation | thickness = generally >{{convert|300|m|ft|abbr=on}} | extent = | area = | map = {{Location map+ | China | relief = 1 | width = 250 | float = center | places = | lat_deg = 33.5 | lon_deg = 109.5 | mark = Yellow pog.svg | marksize = 12 }} | map_caption = }} The Bahe Formation is a Late Miocene (Tortonian/Vallesian/Bahean, about 11.6 to 9.0 mya) geological formation in Shaanxi, China. It has "a complex lithology of predominantly orange-yellow conglomerates, sandstones, tan-yellow sandy mudstones, and tan-red mudstones."[1] The main fossil locality is in the Jiulaopo region on the left bank of the Bahe River in Lantian. Geology and environmentSix general facies have been identified in the region: (1) massive or crudely bedded conglomerates, (2) cross-stratified conglomerate and sandstone deposits, (3) minor sandstone deposits, (4) fine-grained deposits, (5) gritty mudstone and sandstone deposits and (6) marl deposits. The presence of these types of facies suggest active channels, crevasse splays, sheet floods, and floodplains with paleosols and lakes.Thick and laterally pervasive units of fine-grained sediments, formed as suspension fall-out on the floodplain, indicating low-energy conditions and a relatively gentle surface gradient in the area, are by far the most common sedimentary component. Channel-related sandstones and conglomerates indicate that the rivers had a low-sinuosity and were braided, to anastomosing types.[2] Fossil contentMammals
Turtles
References{{Portal|Geology|Paleontology|Neogene|Prehistory of Asia}}1. ^{{cite web|last=Paleobiology Database|title=Miomachairodus details|url=http://paleodb.org/cgi-bin/bridge.pl?a=displayCollResults&taxon_no=41063&max_interval=Miocene&country=China&is_real_user=1&basic=yes&type=view&match_subgenera=1}} 2. ^{{cite web|last=Kaakinen|first=Anu|title=Sedimentation of the Late Miocene Bahe Formation and its implications for stable environments adjacent to Qinling mountains in Shaanxi, China|url=http://www.sciencedirect.com/science/article/pii/S1367912003000440}} 3. ^{{cite web|last=Chow |first=Minchen |title=Tertiary Mammal Faunas of the Lantian Region, Shaanxi Province |url=http://itante.info/2011/76-tiffed-vjpf/ |deadurl=yes |archiveurl=https://web.archive.org/web/20110818175853/http://itante.info/2011/76-tiffed-vjpf/ |archivedate=2011-08-18 |df= }} 4. ^{{cite book|last=Lucas|first=Spencer|title=Chinese fossil vertebrates|publisher=Columbia University Press}} 5. ^{{cite web|last=Zhamg|first=Zhao-Qun|title=Late Miocene Cricetids from the Bahe Formation, Lantian, Shaanxu Province|url=http://www.ivpp.cas.cn/cbw/gjzdwxb/xbwzxz/200811/W020090813369361934628.pdf}} 11 : Geologic formations of China|Neogene System of Asia|Miocene Series|Tortonian|Conglomerate formations|Sandstone formations|Mudstone formations|Marl formations|Fluvial deposits|Paleontology in China|Geography of Shaanxi |
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