New Mexico Geology最新文献

{"title":"Mississippian strata of southeastern New Mexico: distribution, structure, and hydrocarbon plays","authors":"R. Broadhead","doi":"10.58799/nmg-v31n3.65","DOIUrl":"https://doi.org/10.58799/nmg-v31n3.65","url":null,"abstract":"Mississippian strata of southeastern New Mexico are Kinderhookian to Chesterian in age. In Eddy, Lea, and southern Chaves Counties, depth to the top of the Mississip- pian ranges from 5,500 ft in the northwest to 17,000 ft in the southeast. Lower Mississip- pian (Kinderhookian and Osagian) strata are 0-800 ft thick and comprise marine limestones and minor shales and chert. Upper Mississip- pian (Meramecian and Chesterian) strata are 0-600 ft thick and comprise shallow marine limestones and shales. Within the Upper Mis- sissippian section there is a sharp transition from shelf deposits dominated by limestones in the north to the basinal Barnett Shale in the south. Stratigraphic analyses suggest a Missis- sippian ancestry for the Tatum Basin and for the Lower Permian shelf-basin boundary. Forty-five gas and oil pools have been productive from Mississippian reservoirs in Eddy, Lea, and southern Chaves Counties. Twenty-seven pools have been productive from Upper Mississippian reservoirs, and 14 have been productive from Lower Missis- sippian reservoirs. Four gas pools have been productive from both Upper and Lower Mis- sissippian reservoirs. The Mississippian play is one of the least developed plays in south- eastern New Mexico and has yielded a cumu- lative 46 billion ft3 (BCF) gas and 1.4 million bbls oil and condensate (MMBO) from the 45 pools in Eddy, Lea, and southern Chaves Counties. Most production has been obtained from Chesterian limestone reservoirs of the northern shelf. Chesterian reservoirs have been developed in the paleostructurally low Tatum Basin where uppermost Chesterian strata were preserved before deposition of Early Pennsylvanian sediments. Four subplays are identified in the Mississip- pian of Eddy, Lea, and southern Chaves Coun- ties of southeastern New Mexico: (1) Chester shallow marine limestones in the Tatum Basin on the northern shelf; (2) Upper Mississip- pian limestones interbedded with Barnett shales just south of the shelf-basin transition; (3) small and widely disseminated reservoirs in lower Mississippian limestones in the north; and (4) the as-yet untested Barnett Shale in the southern basin.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174213","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":"Cenomanian invertebrate assemblage from the Dakota Sandstone near Ghost Ranch, Rio Arriba County, New Mexico","authors":"S. Lucas, L. Rinehart, S. Kelley","doi":"10.58799/nmg-v31n3.59","DOIUrl":"https://doi.org/10.58799/nmg-v31n3.59","url":null,"abstract":"A small assemblage of invertebrate fossils from the Cretaceous Dakota Sandstone at Arroyo del Yeso near Ghost Ranch, Rio Arriba County, New Mexico, is the first age-diagnostic fossil assemblage documented from the intertongued Dakota–Mancos succession in the Chama Basin. The fossils are assigned to the bivalves Legumen sp., Exogyra sp., Inoceramus arvanus Stephenson, and I. prefragilis Stephenson and the ammonite cf. Acanthoceras amphibolum Morrow. They indicate the Acanthoceras amphibolum Zone of middle Cenomanian age and support lithostratigraphic identification of the fossil-bearing strata as the Paguate Sandstone Tongue of the Dakota Sandstone.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174005","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":"Revisions to the stratigraphic nomenclature of the Abiquiu Formation, Abiquiu and contiguous areas, north-central New Mexico","authors":"F. Maldonado, S. Kelley","doi":"10.58799/nmg-v31n1.3","DOIUrl":"https://doi.org/10.58799/nmg-v31n1.3","url":null,"abstract":"Stratigraphic studies and geologic mapping on the Abiquiu 7.5-min quadrangle have led to revision of the stratigraphic nomenclature for the Oligocene to Miocene Abiquiu Formation in north-central New Mexico. The Abiquiu Formation had previously been defined to include informal upper, middle (Pedernal chert member), and lower members. The basement-derived conglomeratic lower member in the northern Jemez Mountains and Abiquiu embayment is here redefined. We propose removing the “lower member” from the Abiquiu Formation because provenance of these coarse sediments is dramatically different than the volcaniclastic strata of the “upper member.” Furthermore, we propose that the term “lower member of the Abiquiu Formation” be replaced with an existing unit name, the Ritito Conglomerate of Barker (1958), and that the name Abiquiu Formation be restricted to the volcaniclastic succession. The lower part of the Ritito Conglomerate in Arroyo del Cobre on the Abiquiu quadrangle is 47 m (155 ft) thick and is composed of arkosic conglomeratic beds interbedded with arkosic sands and siltstones. Clasts include, in descending order of abundance, Proterozoic quartzite, granite, metavolcanic rocks, quartz, schist, and gneiss and a trace of Mesozoic sandstone and Paleozoic chert. Clasts are predominantly of pebble and cobble size but range from granule to boulder size. Paleocurrent data collected in the Arroyo del Cobre area indicate that the Ritito Conglomerate was deposited by a south-flowing river system during the Oligocene, eroding Laramide highlands such as the Tusas Mountains to the northeast, which contain predominantly Proterozoic rocks. This depositional setting has also been suggested by previous workers. The middle member or Pedernal chert member is present both at the top of the Ritito Conglomerate and as lenses within the lower part of the Abiquiu Formation. This post-depositional diagenetic chert remains an informal unit called the Pedernal chert.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174334","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":"Gallery of Geology - Bosque del Apache oreodont","authors":"J. Love","doi":"10.58799/nmg-v31n4.104","DOIUrl":"https://doi.org/10.58799/nmg-v31n4.104","url":null,"abstract":"","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174462","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 oreodont Merychyus major major (Mammalia: Artiodactyla: Oreodontidae) from the Miocene Popotosa Formation, Bosque del Apache National Wildlife Refuge, Socorro County, New Mexico","authors":"G. Morgan, E. Lander, C. Cikoski, R. Chamberlin, D. Love, L. Peters","doi":"10.58799/nmg-v31n4.91","DOIUrl":"https://doi.org/10.58799/nmg-v31n4.91","url":null,"abstract":"A partial fossilized skeleton of an oreodont (Mammalia: Artiodactyla: Oreodontidae) was discovered in 2008 eroding from the wall of an arroyo on the Bosque del Apache National Wildlife Refuge near San Antonio in Socorro County, central New Mexico. The fossil was preserved in a semi-indurated, sandy stream deposit in a distal piedmont facies of the Miocene Popotosa Formation. The specimen includes a nearly intact skull and attached mandible that were associated with a partial articulated postcranial skeleton. The postcranial skeleton consists of a complete set of thoracic, lumbar, and sacral vertebrae, most of the ribs, which are still attached to their respective thoracic vertebrae, both wrists (distal radius and ulna, carpals, proximal metacarpals), left innominate, and an incomplete left hind limb (femur, tibia, fibula, tarsals). A highly unusual feature is the preservation of an ossified larynx and the delicate hyoid bones. The Bosque del Apache oreodont is identified as Merychyus major major, a member of the subfamily Ticholeptinae. It is the only record of an oreodont from the Popotosa Formation. The specimen represents one of the largest individuals of the genus currently known and the most derived and tapir-like in the degree of posterior retraction of its external narial opening. Merychyus major major is restricted to faunas of early late Miocene (latest Clarendonian) age. Geologic age constraints for the Popotosa Formation in the general vicinity of the oreodont site are provided by two 40Ar/39Ar radioisotopic ages. An age of 14.59 ± 0.05 Ma was obtained on pumice clasts in fluvial sandstones near the base of the local section, and an age of 8.57 ± 0.26 Ma was determined for a basalt flow interbedded with conglomerates near the top. The oreodont skeleton was found in strata somewhat below the dated basalt. The radiometric dates for the Popotosa Formation are consistent with those from the Dove Spring Formation of southern California where the stratigraphic range of M. major major is bracketed by smaller-bodied subspecies of M. major and by vitric tuff units that have been deter mined to be 11.19 ± 0.10 Ma in age, below, and 9.36 ± 0.20 Ma, above.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174942","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":"Evidence for late Pleistocene hydrologic and climatic change from Lake Otero, Tularosa Basin, south-central New Mexico","authors":"B. Allen, D. Love, R. Myers","doi":"10.58799/nmg-v31n1.9","DOIUrl":"https://doi.org/10.58799/nmg-v31n1.9","url":null,"abstract":"Stratigraphic relations, lithofacies, and radiocarbon chronology of deposits that accumulated in and around the margins of late Pleistocene Lake Otero in south-central New Mexico provide evidence for the timing and relative magnitude of episodes of lake expansion that occurred in the basin during the last ice age. The lower few meters of stratified sediment in exposures along the margins of the winddeflated floor of Tularosa Basin contain gypsiferous lithofacies, sedimentary structures, and fossils indicating deposition along the margins of a shallow saline lake. Radiocarbon dates indicate that these basal nearshore lake deposits accumulated from about 45,000–28,000 14C yrs b.p. A widespread erosional episode removed at least 2 m of lake-margin deposits between 28,000 and 25,000 14C yrs b.p. Lakebeds overlying the erosional unconformity contain a relative abundance of siliciclastic sediment and aquatic fossil organisms suggesting repeated episodes of increased precipitation, surface runoff, and freshening of the lake system. These inferred episodes of increased precipitation and enhanced fluvial activity in the basin began ca. 24,500 14C yrs b.p. and lasted for at least 9 millennia. Highstands of the lake during this period appear to have reached an elevation of ~1,204 m. Details of the history of Lake Otero after 15,500 14C yrs b.p. remain sketchy due to wind deflation of the basin floor and wholesale removal of lacustrine deposits during the Holocene. The evidence from Lake Otero for the onset of maximum pluvial conditions during the late Pleistocene appears to be in good temporal agreement with lacustrine reconstructions from neighboring lake basins to the north and south. Additional study of the deposits associated with Lake Otero, including their abundant and diverse assemblages of aquatic fossil organisms, is clearly warranted.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174398","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":"Gallery of Geology - Sierra de Cristo Rey","authors":"S. Hook","doi":"10.58799/nmg-v30n3.93","DOIUrl":"https://doi.org/10.58799/nmg-v30n3.93","url":null,"abstract":"","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174239","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":"Gallery of Geology - Socorro panorama","authors":"R. Chamberlin","doi":"10.58799/nmg-v30n4.113","DOIUrl":"https://doi.org/10.58799/nmg-v30n4.113","url":null,"abstract":"","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174306","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":"Evidence for a Tyrannosaurus rex from southeastern Colorado","authors":"G. Osborn, K. Berry","doi":"10.58799/nmg-v30n1.12","DOIUrl":"https://doi.org/10.58799/nmg-v30n1.12","url":null,"abstract":"Order SauriSchia Seeley 1888 Family TyrannoSauridae Osborn 1905 Genus Tyrannosaurus Osborn 1905 cf. T. rex Osborn 1905 Referred specimens—TSJC 2008.1.1; TSJC 2008.1.2; TSJC 2008.1.3. Description—Tooth: A tyrannosaurid tooth (TSJC 2008.1.1) most closely resembles the teeth of “Nanotyrannus lancensis” (or adolescent T. rex, Carr and Williamson 2004) based on crown shape and serration density (N. Larson, pers. comm. 2007). In straight-line measurement, the tooth is approximately 3.5 cm from tip to base. The serration density along the anterior carina is 12/cm, justifying the diagnosis as T. rex (Farlow et al. 1991). The tooth is slightly recurved, blunt, bears denticles along its anterior carina, and is broken at its base. Femur: A limb bone fragment (TSJC 2008.1.2) is also tentatively identified as cf. T. rex. Theropod bones commonly exhibit onion-skin layering in cross section (K. Carpenter, pers. comm. 2007), and this bone seems to lack this feature, although the bone has distinct, differentiable layers. Whereas the bone itself may not be exclusively attributed to a theropod based on its gross histological properties alone, there are quantitative reasons supporting this diagnosis. First, the bone fragment is circular in cross section, and intersecting perpendicular bisectors of lines secant to its intact, periosteal surface suggest a radius of 90 ± 0.1 mm. As long bone circumference is used to estimate a live animal’s weight (Anderson et al. 1985; Alexander 1989), a 90 mm radius corresponds to a biped weighing approximately 5.23 metric tons. In Maastrichtian time in western North America, this value is exclusive to T. rex as far as mass estimates based on long bone circumferences for bipeds are concerned (Alexander 1989; Horner et al. 2004). Second, as T. rex femora have circular cross sections at their midpoint (Farlow et al. 1995; Holtz 2004) and the published growth curve for T. rex is based on midshaft femoral measurements (Erickson et al. 2004), it is possible to quantitatively compare the published growth curve for T. rex with the growth pattern observed in this specimen. Measuring the midpoint of each growth line to an accuracy of ± 0.5 mm along a radial transect, T. rex annual growth markers are exceptionally good predictors for the growth lines observed in this bone (cχ2 = 1.44, df = 6, p-value > 0.95). As T. rex is the only animal known to exhibit this characteristic pattern of growth (Erickson et al. 2004; ChinsamyTuran 2005), this is believed to be a fairly powerful diagnostic test. Significance—Estimated to be about 71 m.y. old based on the age of the Baculites eliasi ammonite zone, these fossils may be among the oldest known T. rex fossils (D. Wolberg, pers. comm. 2007). Institutional abbreviation—TSJC, Trinidad State Junior College Louden-Henritze Archeology Museum.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71173870","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":"Upper Cretaceous molluscan record along a transect from Virden, New Mexico, to Del Rio, Texas","authors":"W. A. Cobban, S. Hook, K. C. McKinney","doi":"10.58799/nmg-v30n3.75","DOIUrl":"https://doi.org/10.58799/nmg-v30n3.75","url":null,"abstract":"Updated age assignments and new collections of molluscan fossils from lower Cenomanian through upper Campanian strata in Texas permit a much refined biostratigraphic correlation with the rocks of New Mexico and the Western Interior. Generic names of many Late Cretaceous ammonites and inoceramid bivalves from Texas are updated to permit this correlation. Strata correlated in the west-to-east transect include the lower Cenomanian Beartooth Quartzite and Sarten Sandstone of southwest New Mexico, and the Eagle Mountains Formation, Del Rio Clay, Buda Limestone, and basal beds of the Chispa Summit, Ojinaga, and Boquillas Formations of the Texas–Mexico border area. Middle Cenomanian strata are lacking in southwestern New Mexico but are present in the lower parts of the Chispa Summit and Boquillas Formations in southwest Texas. Upper Cenomanian and lower Turonian rocks are present at many localities in New Mexico and Texas in the Mancos Shale and Chispa Summit, Ojinaga, and Boquillas Formations. Middle Turonian and younger rocks seem to be entirely nonmarine in southwestern New Mexico, but they are marine in the Rio Grande area in the Chispa Summit, Ojinaga, and Boquillas Formations. The upper part of the Chispa Summit and Boquillas contain late Turonian fossils. Rocks of Coniacian and Santonian age are present high in the Chispa Summit, Ojinaga, and Boquillas Formations, and in the lower part of the Austin. The San Carlos, Aguja, Pen, and Austin Formations contain fossils of Campanian age. Fossils representing at least 38 Upper Cretaceous ammonite zones are present along the transect. Collections made in recent years in southwestern New Mexico and at Sierra de Cristo Rey just west of downtown El Paso, Texas, have been well treated and do not need revision. Taxonomic names and zonations published in the pre-1970 literature on the Rio Grande area of Texas have been updated. New fossil collections from the Big Bend National Park, Texas, allow for a much refined correlation in the central part of the transect in Texas. Middle Turonian–Campanian zonation in southwest Texas is based mainly on ammonites of the Family Collignoniceratidae, as opposed to the scaphitid and baculitid ammonites that are especially abundant farther north in the Western Interior.","PeriodicalId":35824,"journal":{"name":"New Mexico Geology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71174130","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}