Geology of the Chama Basin最新文献

{"title":"Dakota outcrop geology and sequence stratigraphy, Chama Basin, New Mexico","authors":"P. Varney","doi":"10.56577/ffc-56.193","DOIUrl":"https://doi.org/10.56577/ffc-56.193","url":null,"abstract":"—The Dakota Formation of the Chama Basin records the initial incursion of the Western Interior Seaway into the study area. Dakota outcrops on US Highway 84, northwest of the Ghost Ranch, and at Heron Dam, south of Chama, New Mexico correlate with each other and with well logs located 19 and 44 miles (30.4 and 70.4 km) to the west based on comparison with outcrop gamma-ray logs. The outcrops contain three Dakota depositional sequences defined by unconformities. One of the sequence-bounding surfaces within the formation, S3, truncates and replaces the K2 unconformity between Lower and Upper Cretaceous units and, thus, has regional importance. Sequence stratigraphic variations in the Dakota have economic significance because they may control fluid distribution in the subsurface. FIGURE 1. Index map showing the two outcrop locations discussed in this paper and their relationship to Chama, Abiquiu Lake and the Ghost","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122738151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The White Rock Mesa Member of the Dakota Sandstone (Cretaceous) of the San Juan Basin, New Mexico and Colorado, a formal new lithostratigraphic unit to replace the informal \"Dakota Main Body\"","authors":"Donald E. Owen","doi":"10.56577/ffc-56.227","DOIUrl":"https://doi.org/10.56577/ffc-56.227","url":null,"abstract":"—The White Rock Mesa Member of the Dakota Sandstone in the San Juan Basin of New Mexico and Colorado is formally named in this paper to replace the informal “Dakota main body” from a stratotype near Gallup, NM. It is an eastwardthinning clastic wedge of fluvial sandstone, carbonaceous shale, and coal that rests on the K-3 unconformity, which truncates lower Dakota members, the Burro Canyon Formation, and the Morrison Formation. A series of marine-flooding surfaces mark the top of the White Rock Mesa Member, and it grades into shoreface sandstones of the lower parasequence of the Cubero Sandstone Tongue of the Dakota to the east. It averages approximately 30 meters in thickness and is present in the western two thirds of the San Juan Basin. FIGURE 1. Topographic map of White Rock Mesa. Stratotype measured approximately along horizontal bar at west end of White Rock Mesa. USGS Church Rock 7.5’ Quadrangle.","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133681786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regional tectonic inferences for the 1.4 Ga-Holocene lateral slip history of the Picuris-Pecos and related faults, northern New Mexico","authors":"S. Cather, J. Timmons, K. Karlstrom","doi":"10.56577/ffc-56.93","DOIUrl":"https://doi.org/10.56577/ffc-56.93","url":null,"abstract":"A BSTRACT . —Dextral discontinuities evident from analysis of aeromagnetic maps for northern New Mexico, corresponding primarily to the north-striking Picuris–Pecos, the Tusas–Picuris, and the Nacimiento fault systems, together yield at least ~55 km and perhaps as much as ~90 km of net dextral separation. A strike-slip origin for these separations, however, has been clearly demonstrated by geologic mapping only for the Picuris–Pecos fault and, less concisely, for the Tusas–Picuris fault. The age of the Picuris–Pecos fault is younger than ~1.45 Ga because it cuts dated foliations of that age in the Picuris Mountains. The lack of mylonites along the Picuris–Pecos fault also indicates it is not older than ~1.2–0.8 Ga, the age when the basement rocks of the Sangre de Cristo Mountains last cooled through temperatures characteristic of the brittle-ductile transition (300–200°C). To help unravel the reactivation history of the Picuris–Pecos and related faults, the directions of horizontal shortening and/or extension were analyzed for the eight major deformations that have affected the region from 1.4 Ga to the Holocene. For each of these eight tectonic episodes, the resolved lateral shear sense (dextral or sinistral) for north-striking faults in northern New Mexico was inferred. Although there is no direct evidence for Proterozoic slip on the Picuris–Pecos or related faults, such slip seems probable given that Phanerozoic movements often reactivated older structures. Mesoproterozoic slip (~1.4 Ga, ~1.1 Ga) was potentially sinistral based on regional deformation patterns and the postulated long-lived contractional plate margin along southern Laurentia. Neoproterozoic slip (~0.8 Ga) would have been extensional, with a possible sinistral component. Possible Cambrian slip accompanying the opening of the southern Oklahoma aulacogen would have been dextral but of small magnitude (a few km). The earliest documented slip on any of the faults (Picuris–Pecos, Nacimiento) is late Paleozoic. Lateral slip on north-striking faults in northern New Mexico during the late Mississippian–early Permian Ancestral Rocky Mountain orogeny was probably dextral and possibly of large magnitude. Laramide fault slip was also dextral and probably large (tens of km). The lateral slip component during the main phase of Rio Grande rifting (Miocene) was sinistral but of small magnitude. Lateral components during late rifting (latest Miocene–Holocene) are indeterminate, but small. The 55–90 km net dextral separation on north-striking faults in northern New Mexico is probably the cumulative result of numerous tectonic events, not all of them dextral. If our analysis is correct, then the Ancestral Rocky Mountain and Laramide events are most likely responsible for the majority of the dextral separations seen today. The relative importance of dextral contributions by these two orogenies, however, has not yet been determined.","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121371228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trackway of a giant Arthropleura from the Upper Pennsylvanian of El Cobre Canyon, New Mexico","authors":"S. Lucas, A. J. Lerner, J. Hannibal, A. Hunt, J. Schneider","doi":"10.56577/ffc-56.279","DOIUrl":"https://doi.org/10.56577/ffc-56.279","url":null,"abstract":".— We document a giant terrestrial arthropod trackway assigned to Diplichnites cuithensis Briggs, Rolfe and Brannan, 1979 from the nonmarine redbeds of the Cutler Group (Late Pennsylvanian, Missourian?) in El Cobre Canyon, New Mexico,","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115442434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stratigraphy and depositional trends in the Santa Fe Group near Espanola, north-central New Mexico: tectonic and climatic implications","authors":"D. Koning, S. Connell, G. Morgan, L. Peters, W. Mcintosh","doi":"10.56577/ffc-56.237","DOIUrl":"https://doi.org/10.56577/ffc-56.237","url":null,"abstract":"— Exposures of the Miocene Tesuque and Chamita Formations and interbedded tephra zones provide a record of extensional basin evolution in the northern Española basin of the northern Rio Grande rift. Geologic studies of these strata resulted in the definition of the Cuarteles Member (new name) in both the Tesuque and Chamita Formations. The Cuarteles Member is a 180 m-thick succession of light brown to reddish yellow to pink arkosic sandstone together with graniteand quartzite-bearing conglomerate derived from the Sangre de Cristo Mountains. It was deposited in an alluvial slope environment on the eastern basin margin. Six laterally extensive tephra-bearing intervals have been mapped in the study area and correlated between measured stratigraphic sections. The age of these tephra-bearing intervals are generally well-constrained and are used to estimate rates of stratal tilting and stratal accumulation during middle and late Miocene time. Additional geochronologic controls come from middle Miocene (late Barstovian) mammal fossils in these deposits. There is a noteworthy decrease in stratal tilt rates and sediment accumulation rates after about 13-14 Ma. This decrease is generally coincident with an overall coarsening of the stratigraphic succession and basinward progradation of deposits represented by the Cuarteles Member. The rate change in both stratal tilt and stratal accumulation rate data indicates a decrease in tectonic subsidence of the Española basin after about 13-14 Ma. The overall increase in the proportion of coarse channel deposits and clast sizes, in addition to the progradation of basin-margin detritus, after 13-14 Ma does not agree with previous half-graben models that relate tectonic subsidence with deposition. These sedimentologic changes could be the result of the Española basin transitioning from an underfilled to overfilled condition as the rate of tectonic subsidence decreased. Other factors besides tectonic changes that could have influenced this coarsening and progadation include: 1) a change in climate as inferred from the emplacement of a major dune field and marine proxy records, and 2) geomorphic changes in streams draining the Sangre de Cristo Mountains. that the basin here is a west-tilted half-graben. The Pajarito and Santa Clara faults, in addition to possible faults to the west buried by younger volcanic rocks, probably act as master faults for the half-graben (Golombek, 1983; Harrington and Aldrich, 1984; Baldridge et al., 1994; Koning et al., 2004b). A structurally shallower FIGURE 1. Location map of the northern Española and southern San Luis basins. The area of the geologic map of Figure 2 (the study area) is shown by the rectangle near the city of Española. Major geologic structures are shown by white lines, with the small perpendicular bars indicating throw direction of normal and normal-oblique faults. Important faults are abbreviated as: PFZ = Pajarito fault zone, SCF = Santa Clara fault, OCF = Ojo Caliente ","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131605968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early Permian vertebrate assemblage and its biostratigraphic significance, Arroyo del Agua, Rio Arriba County, New Mexico","authors":"S. Lucas, S. Harris, J. Spielmann, D. Berman, A. Henrici, A. Heckert, K. Zeigler, L. Rinehart","doi":"10.56577/ffc-56.288","DOIUrl":"https://doi.org/10.56577/ffc-56.288","url":null,"abstract":"Early Permian vertebrate fossils from the upper part of the El Cobre Canyon Formation of the Cutler Group in \u0000the area around Arroyo del Agua, Rio Arriba County, New Mexico, encompass an extensive assemblage of chondrichthyans, \u0000osteichthyans, temnospondyls, microsaurs, a seymouriamorph, diadectomorphs, a parareptile, captorhinomorphs, an araeoscelid, \u0000and basal or pelycosaurian-grade synapsids. This long and extensively collected and studied vertebrate assemblage comes from a narrow stratigraphic interval about 50-60 m thick, and we treat it as a single biostratigraphic assemblage. The presence of Zatrachys, Bolosaurus and Chenoprosopus indicates correlation of this assemblage to the Bowie Group in Texas, and thus \u0000suggests an age for the upper El Cobre Canyon Formation of early Wolfcampian.","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128662680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stromatolites in the Todilto Formation?","authors":"D. Ulmer-Scholle","doi":"10.56577/ffc-56.380","DOIUrl":"https://doi.org/10.56577/ffc-56.380","url":null,"abstract":"—The Middle Jurassic Todilto Formation is found in northern New Mexico and southwestern Colorado. In the Ambrosia Lake uranium district, previous workers have identified the large fold-like features in the Todilto Formation as intraformational folds that were produced by loading of the overlying Middle-Upper Jurassic eolian Summerville Formation on the water-saturated sediments of the Todilto Formation or by later structural deformation. A re-interpretation of the outcrops of Green (1982) near Mesa Montañosa, based on preliminary field data, suggests that these features are large, domal stromatolites or bioherms. The composition and morphology of these structures indicate microbial growth rather than loading as the source of the mounds. While similar structures elsewhere in the Todilto Formation have been attributed to intraformational or tectonic deformation, this study suggests that there may be more than one mechanism capable of producing fold-like structures in the Todilto Formation, and a reassessment of previously identified structures may be needed. FIGURE 1. The study area within the Ambrosia Lake uranium district, New Mexico. 381 STROMATOLITES IN THE TODILTO FORMATION? basin (Fig. 2). It is conformably underlain by the eolian, Middle Jurassic Entrada Sandstone and overlain by the lacustrine and sabkha deposits (Kirkland et al., 1995) of the Middle-Upper Jurassic Summerville Formation (Fig. 3). The Todilto Formation ranges in thickness from 10 to almost 40 m and consists of two members: the lower limestone Luciano Mesa Member and the upper gypsum Tonque Arroyo Member (Fig. 3). The age of the Todilto Formation, based on fossil evidence compiled by Lucas et al. (1985), is Middle Callovian (~159 Ma). Berglof (1992) considers the uranium ores to be syndepositional. Isotopic ages for uraninite within the Todilto Formation provide an age of 150 to 155 Ma. Paleogeographic and paleoclimatic reconstructions (Fig. 4, Scotese et al., 2005) for this time period place the Todilto Formation at approximately 20°N latitude in an arid climatic belt. Over the years, a significant debate has existed over the Todilto’s depositional environment. Some authors suggested that the carbonates and evaporates are marine (Baker et al., 1947; Evans and Kirkland, 1988; Harshbarger et al., 1957; Imlay, 1952; Ridgley and Goldhaber, 1983), others proposed a non-marine, lacustrine origin (Anderson and Kirkland, 1960; Rapaport et al., 1952; Tanner, 1970), and yet others proposed a coastal salina that may have been periodically flooded by marine waters (Anderson and Lucas, 1993; Armstrong, 1995; Lucas et al., 1985; McCrary, 1985). Kirkland et al. (1995), based on paleontology, sedimentology and the isotopic data (carbon, strontium and sulfur), concluded that the Lucas et al. (1985) model of a coastal salina with a complex interplay of both marine and freshwaters best explains the Todilto deposits. More recently, Benan and Kocurek (2000), based on the Todilto Formation fillin","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126908364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pleistocene vertebrates from Rio Arriba and Taos counties, northernmost New Mexico","authors":"G. Morgan, S. Lucas, G. Spencer","doi":"10.56577/ffc-56.416","DOIUrl":"https://doi.org/10.56577/ffc-56.416","url":null,"abstract":"—Nine Pleistocene vertebrate fossil sites are known from Rio Arriba and Taos counties in northernmost New Mexico: Gobernador, Youngsville, Abiquiu, Santa Cruz, Ojo Caliente, and San Antonio Mountain (SAM) Cave in Rio Arriba County and Mesa Vibora, Picuris, and Vadito in Taos County. The Gobernador site in northwestern Rio Arriba County is in the Colorado Plateau physiographic province, and the Santa Cruz site in southeastern Rio Arriba County is in the Basin and Range province; the other seven sites are located in the Southern Rocky Mountains province. All nine Pleistocene sites from these two counties occur above 6000 ft (1830 m) in elevation, and SAM Cave is the highest Pleistocene site in New Mexico at 8980 ft (2737 m). Six of the nine sites from Rio Arriba and Taos counties contain a single species of large mammal: Gobernador (Equus niobrarensis), Youngsville (Mammuthus columbi), Ojo Caliente (proboscidean, probably mammoth), Mesa Vibora (Bison sp.), Picuris (Mammuthus sp.), and Vadito (Mammuthus columbi). The Abiquiu site has three large mammals (Euceratherium collinum, Bison antiquus, and Mammuthus sp.), and Santa Cruz has five large mammals (Canis dirus, Equus sp., Camelops hesternus, Bison sp., and Mammuthus sp.). SAM Cave has the most diverse Pleistocene vertebrate fauna in this region (41 species), almost all of which are small species. SAM Cave is the oldest Pleistocene vertebrate fauna in these two counties, dating to the late early Pleistocene (medial Irvingtonian, ~0.74-0.99 Ma). The Youngsville, Abiquiu, Santa Cruz, Mesa Vibora, and Vadito sites are medial or late Pleistocene (Rancholabrean) in age based on the presence of Bison or Mammuthus columbi, both of which are typical of Rancholabrean faunas. The only Pleistocene site from this region with an absolute date is Mesa Vibora; an AMS radiocarbon date of 24,740 ± 140 years Before Present, on bone collagen from a Bison humerus. FIGURE 1. Map of New Mexico showing the location of Pleistocene vertebrate sites in Rio Arriba and Taos counties. Numbers refer to the following sites described in the text: 1. Gobernador; 2. Youngsville; 3. Abiquiu; 4. Santa Cruz; 5. Ojo Caliente; 6. San Antonio Mountain (SAM) Cave; 7. Mesa Vibora; 8. Picuris; 9. Vadito. 417 PLEISTOCENE VERTEBRATES FROM RIO ARRIBA AND TAOS COUNTIES the earliest mammoth records in North America (~1.6 Ma) are from early Irvingtonian sites in New Mexico—Tijeras Arroyo in Bernalillo County and Mesilla Basin fauna C in Doña Ana County—although neither of these sites occurs in the region covered in this paper. The only Irvingtonian vertebrate fauna in this area is the medial Irvingtonian SAM Cave fauna. Late medial and late Pleistocene (~10-300 ka) vertebrate faunas are placed in the Rancholabrean NALMA, defined by the first appearance in North America of the genus Bison, also an immigrant from Eurasia. Three of the faunas in this region, Abiquiu, Santa Cruz, and Mesa Vibora, contain Bison, and are thus Rancholabrean in age. Two","PeriodicalId":345302,"journal":{"name":"Geology of the Chama Basin","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121773557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}