{"title":"LATE PLIOCENE (BLANCAN) VERTEBRATE FAUNAS FROM PEARSON MESA, HIDALGO COUNTY, NEW MEXICO AND GREENLEE COUNTY, ARIZONA","authors":"G. Morgan, P. Sealey, S. Lucas","doi":"10.56577/sm-2008.892","DOIUrl":"https://doi.org/10.56577/sm-2008.892","url":null,"abstract":"Exposures at Pearson Mesa in the Duncan basin along the New Mexico-Arizona border have produced a diverse assemblage of late Pliocene (Blancan) vertebrates. The stratigraphic section at Pearson Mesa consists of more than 60 m of sandstones, mudstones, and sedimentary breccias of the Gila Group. Two distinct vertebrate faunas occur at Pearson Mesa: the early late Blancan Pearson Mesa Local Fauna (LF) is derived from the lower 15 m of the stratigraphic section and the latest Blancan Virden LF occurs in the upper 20 m of the section. The Pearson Mesa fauna consists of 25 species: 3 land tortoises ( Gopherus and two species of Hesperotestudo ); box turtle ( Terrapene ); colubrid snake; bird; and 19 mammals. Age-diagnostic mammals from the Pearson Mesa LF include: the ground sloth Paramylodon cf. P. garbanii ; the pocket gopher Geomys persimilis ; the cotton rat Sigmodon medius ; the three-toed horse Nannippus peninsulatus ; the one-toed horses Equus cf. E. cumminsii , and E. simplicidens ; and the peccary Platygonus bicalcaratus . The association of Paramylodon and Nannippus defines a restricted interval of time in the Blancan between the first appearance of South American immigrants (including Paramylodon ) in the southwestern US at ~3.0 Ma and the extinction of Nannippus at ~2.2 Ma. Magnetostratigraphy further constrains the age of the Pearson Mesa LF, with five normally-magnetized samples from the lower part of the section referred to the uppermost Gauss Chron (Chron 2An.1n; 2.58-3.04 Ma). Southwestern early late Blancan faunas (~2.6-3.0 Ma) correlative with Pearson Mesa include: Anapra, NM; Wolf Ranch and 111 Ranch, AZ; and Cita Canyon and Hudspeth, TX. A 10-m-thick sedimentary breccia overlying the Pearson Mesa LF lacks fossils and may represent a hiatus. The Virden LF consists of 22 species: toad; large Hesperotestudo ; Terrapene ; colubrid snake; lizard; two birds; and 15 mammals. A latest Blancan age (~1.8-2.2 Ma) for the Virden LF is indicated by the presence of the dwarf cotton rat Sigmodon minor and the small camelid Hemiauchenia gracilis , both restricted to latest Blancan faunas, and the association of the glyptodont Glyptotherium arizonae with the coyotelike canid Canis lepophagus . Southwestern latest Blancan faunas correlative with Virden include: La Union, NM and Curtis Ranch and San Simon, AZ.","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114395689","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 RIO GRANDE RIFT IN MEXICAN PERSPECTIVE","authors":"W. E. Elston","doi":"10.56577/sm-2008.872","DOIUrl":"https://doi.org/10.56577/sm-2008.872","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114603185","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":"PENNSYLVANIAN STRATIGRAPHY ON THE NORTHERN FLANK OF THE OSCURA MOUNTAINS, SOCORRO COUNTY, NEW MEXICO","authors":"S. Lucas, K. Krainer, L. Rinehart, J. Spielmann","doi":"10.56577/sm-2008.887","DOIUrl":"https://doi.org/10.56577/sm-2008.887","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":" 30","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114060751","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":"SUMMARY OF THE GEOLOGY, GEOCHRONOLOGY, AND GEOCHEMISTRY OF THE ABIQUIU 1:24,000 QUADRANGLE AND CONTIGUOUS AREAS, NORTH-CENTRAL NEW MEXICO","authors":"F. Maldonado, D. Miggins, J. Budahn","doi":"10.56577/sm-2008.890","DOIUrl":"https://doi.org/10.56577/sm-2008.890","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126406856","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":"SEDIMENTOLOGY AND PROVENANCE OF BASIN-FILL STRATA AS A GUIDE TO FAULT EVOLUTION, SOUTHERN RIO GRANDE RIFT","authors":"G. Mack, W. Seager","doi":"10.56577/sm-2008.889","DOIUrl":"https://doi.org/10.56577/sm-2008.889","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131180764","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":"LINKS BETWEEN THIRD-ORDER (My-SCALE) SEA-LEVEL AND CLIMATE CHANGE IN THE UPPER ORDOVICIAN MONTOYA GROUP, SOUTHERN NEW MEXICO","authors":"M. A. Tyra, M. Elrick, V. Atudorei","doi":"10.56577/sm-2008.909","DOIUrl":"https://doi.org/10.56577/sm-2008.909","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"165 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132655214","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":"BITE MARKS ON A SKULL OF PSEUDOPALATUS MCCAULEYI (ARCHOSAURIA: CRUROTARSI: PHYTOSAURIDAE) FROM THE UPPER TRIASSIC BULL CANYON FORMATION, EASTERN NEW MEXICO","authors":"L. Rinehart, A. Heckert, S. Lucas, D. C. Bond","doi":"10.56577/sm-2008.898","DOIUrl":"https://doi.org/10.56577/sm-2008.898","url":null,"abstract":"A 1.12 meter-long brachyrostral phytosaur skull (NMMNH P- 56187) from the Upper Triassic Bull Canyon Formation of eastern New Mexico is assigned to Pseudopalatus mccauleyi based on its poorly preserved, but apparently depressed supratemporal fenestrae, its subtriangular squamosal process, and completely crested rostrum. The skull is obliquely flattened, exposing the left side of the face and skull roof. The lachrymal - nasal area, bounded by the external nares, antorbital fenestra (aofe) and orbit, on the left side is punctured by three large holes, one immediately dorsal to the middle of the aofe and two more (paired?) posterior to the first and approximately halfway between the aofe and the orbit. Based on size and shape, these holes appear to represent bite marks, probably from another (possibly conspecific) phytosaur. The three marks thus form an “L” and probably represent two teeth from one side of the biting animal’s jaw and a one from the other, although the orientation of attack is not clear. The larger holes may mark wounds inflicted by the large teeth in the “bulb” of a phytosaur snout, with the smaller injury attributed to a smaller, more posterior tooth. The edges of the holes are smooth and rounded, evidently having healed. The tooth marks measure: (1) 27 X 10 mm, (2) 25 X 13 mm, and (3) 16 X14 mm. The combination of elongate and approximately round punctures supports assignment of the bite mark to the ichnotaxon Heterodontichnites hunti . This is only the second bite mark on a phytosaur fossil of which we are aware. The other is in the palate of a large skull of Redondasaurus bermani (NMMNH P-31094) from the Redonda Formation of east-central New Mexico. This injury comprises three smaller (9 to 12 mm), approximately round punctures in a gently curved line that is 45 mm long. These punctures show healed edges and may have been self-inflicted. Thus, the Pseudopalatus bite mark is the first unambiguous evidence of a phytosaur suffering an attack from another phytosaur of which we are aware.","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"10 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131635945","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":"SOIL GEOMORPHIC PATTERNS AND GRASSLAND RESISTANCE AT THE JORNADA BASIN LTER SITE","authors":"D. Rachal, H. Monger, D. Peters","doi":"10.56577/sm-2008.895","DOIUrl":"https://doi.org/10.56577/sm-2008.895","url":null,"abstract":"Geomorphic properties, such as elevation, slope gradient, and orientation, are fundamental elements of the landscape that play a large role in the persistence of desert grasslands. Microclimatic variations created by these landform elements can control physical and chemical weathering rates of parent material. Topographic location (e.g. Run-on vs. Run-off position) can control the redistribution of this weathered material, which can influence the movement of nutrients and sediments by wind and water throughout an ecosystem. Over time, the process of erosion and sedimentation differentiates the landscape into individual soil units that vary in age, physical, and chemical composition. Upon these soil-geomorphic entities, isolated patches of grasslands can be found in the Jornada Basin, New Mexico. These grass patches are resistant against the transition from semi-arid, perennial grasslands to a shrub dominated ecosystem that began within the Jornada Basin 150 years ago. The survival of these remnant grasslands are strongly influenced by vegetation-soil-landform relationships. Therefore, the soil-geomorphic properties of a specific landscape can provide a stronghold for grass species to resist and survive the detrimental effects of desertification, thus, producing the isolated grass patches that are observed today in the Jornada Basin.","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132861310","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":"GENESIS OF FAULT BRECCIA AT DEER CREEK: IMPLICATIONS FOR THE SLIP HISTORY OF THE PICURIS–PECOS FAULT","authors":"S. Cather, A. Read, S. Kelley, D. Ulmer-Scholle","doi":"10.56577/sm-2008.865","DOIUrl":"https://doi.org/10.56577/sm-2008.865","url":null,"abstract":"Spectacular fault breccia up to 250 m wide is exposed at Deer Creek along the Picuris– Pecos fault (PPf), ~18 km southeast of Santa Fe. There, the PPf juxtaposes Middle Pennsylvanian–Permian strata (Alamitos Fm and Sangre de Cristo Fm) with Proterozoic granitegneiss on the west. In addition to the ~38 km dextral separation documented elsewhere along the fault, the PPf at Deer Creek shows stratigraphic evidence for ~300 m of east-down separation. The breccia consists of two zones: (1) An eastern zone, 10–50 m wide, directly west of the PPf, within which clasts of Proterozoic gneiss exhibit diverse foliation orientations within individual outcrops. Also in this zone are sparse, meter-scale blocks of indurated Mississippian– Pennsylvanian sedimentary rocks and significant fine-grained cataclasite. We interpret this breccia zone as recording dilation and shear in a high-strain zone adjacent to the PPf. (2) A western zone up to 200 m meters wide has low dispersion of foliation orientations within individual outcrops. This zone exhibits relatively minor fine-grained cataclasite, is strongly indurated by red jasperoid, and locally is cut by less-brecciated pods of Mississippian carbonate (probable fissure fills) and Pennsylvanian–Permian arkosic sandstone. We interpret this breccia zone to have formed by weak dilational strain. In both breccia zones, the average orientation of foliation is rotated ~20-30° anticlockwise relative to that in undeformed gneiss to the west. This rotation occurred before widespread Permian remagnetization in the area, as no significant vertical-axis","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134260040","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":"GEOHYDROLOGIC INVESTIGATION OF THE SOUTHERN CHUPADERA MOUNTAINS AREA: AVAILABILITY AND SUSTAINABILITY OF WATER SUPPLIES FOR DOMESTIC USE","authors":"Michael J. Darr","doi":"10.56577/sm-2008.868","DOIUrl":"https://doi.org/10.56577/sm-2008.868","url":null,"abstract":"","PeriodicalId":435999,"journal":{"name":"New Mexico Geological Society, 2008 Annual Spring Meeting, Proceedings Volume","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121984079","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}