Donald L. Wolberg

Analysis of gaseous inclusions in fossil resin from a late cretaceous stratigraphic sequence

It is the purpose of this work to analyze the fluids included in the Fossil Forest fossil resin. The fossil resin samples used in this study were collected from the Fruitland Formation (Campanian-Maastrichtian; 76-72 Ma), a sequence of interbedded coals, drab-colored mudstones and claystones, poorly fissile carbonaceous shales, siltstones and sandstone in the Fossil Forest study area located in the west-central San Juan Basin of New Mexico. The resin is found in association with and included in fossilized taxodiaceous wood. The fluids trapped in Late Cretaceous fossil resin have a higher oxygen content that is found in younger samples. The analytical data are presented in a framework devised to differentiate between trapped paleoatmospheres and gases dissolved in the amber matrix. The data suggest that the Late Cretaceous atmosphere had an O2 content of at least 24%. The gases trapped in fossil resin most likely are not pristine paleoatmosphere. However, fossil resin can record the composition of the atmosphere over the past 120 m.y., the length of the resin record.

A NEW LATE CRETACEOUS (CAMPANIAN-MAASTRICHTIAN) AMIID (HALECOMORPHI: ACTINOPTERYGII) FROM THE FRUITLAND FORMATION, SAN JUAN BASIN, NEW MEXICO

Amia? chauliodeia, a new amiid fish from the Late Cretaceous Fruitland Formation of the San Juan Basin, New Mexico, is described from material that includes vertebral centra, elements of the mandibular arch, dermal skull roof, palatal complex, hyoid arch, pectoral girdle, branchial apparatus, ribs, and both pelvic basipterygia. The new form differs from previously described amiiforms in the length of the dentary tooth row, in the anterior thickness of the dentary, and in the apparent lack of internal sensory canals in the dentary and angular. The New Mexico amiid also retains a primitive metapterygoid. Although the new form shares several features in common with the Late Cretaceous amiid Melvius thomasi described by Bryant (1987), it is unquestionably distinct from this form. Material from the Fruitland and Kirtland Formations of New Mexico referred by Bryant (1987) to M. thomasi is now included within Amia? chauliodeia. mation of northwestern New Mexico. This new species is com- pared with Amia calva and several fossil amiiform species. Other fossil vertebrates from the Fossil Forest study area include chon- drichthyans, other osteichthyans (including Lepisosteus and Paralbula), turtles, lizards, crocodiles, dinosaurs, mammals, and isolated elements (teeth and vertebrae) attributed to Kindleia fragosa.

Fifth notice of transfer of specimens figured by Rousseau H. Flower

This notice is the fifth in a series recording the transfer of fossils described by Rousseau H. Flower (1913-1988) to the Smithsonian Institution and the U.S. National Museum. During a long, productive, and colorful career, Rousseau described more than 400 new fossil taxa (Wolberg, 1988). Most of Rousseaus fossils have been maintained in the collections of the New Mexico Bureau of Mines and Mineral Resources. The fossils in this transfer were sent to Rousseau in 1952 by William J. Sando, then a graduate student at Johns Hopkins University, who collected them during his research on the Beekmantown Group of Maryland (Sando, 1957). In 1955, Rousseau submitted a manuscript to the Journal of Paleontology and this was published in 1956. Some controversy seems to have surrounded the publication of the paper; we have found a file of correspondence related to that publication and it is very “Roweresque” in content. In addition, Rousseau cataloged the Sando fossils into the NMBM&MRs collection, but from the associated correspondence there seems to be little doubt but that the collection was intended to be reposited in the Smithsonian.

Proceedings of the Eighty-fourth Annual Meeting Cincinnati, Ohio, October 25–28, 1992

The Outgoing Council met Sunday, October 25, 1992, in the Hyatt, Bluegrass Room A-B, in Cincinnati, Ohio. The meeting was called to order by President Kaesler at 7:00 PM. Present for the Outgoing Council Meeting were: Roger Kaesler, Tom Bolton, Rod Feldmann, Steve Stanley, June Ross, Don Wolberg, Don Steinker, Arnie Miller, Carl Koch, Steve Culver, and Scott Lidgard. President Kaesler asked for a motion to approve the agenda and June Ross so moved, Rod Feldmann seconded the motion, which passed without objection.

Third notice of transfer of cephalopods described and figured by Rousseau H. Flower

Rousseau H. Flower (1913-1988) described and figured more than hundreds of fossil taxa, collected throughout the world, during his long and colorful career (Wolberg, 1988). Most of the fossils Flower worked with remain at the New Mexico Bureau of Mines and Mineral Resources (NMBMM a large proportion of the fossils actually belong to other institutions. The NMBM&MR continues to receive requests for published specimens and is making every effort to return loan material. The NMBM&MR also believes that the professional community would be best served by maintenance of the Flower/NMBM&MR fossils in a national repository. It was Rousseaus wish that the Smithsonian Institution/U. S. National Museum serve as one of the repositories of the NMBM&MR collections.

Paleoenvironmental Implications of First Documented Occurrence of Unusual Carbonate Mineral, Huntite, in Late Cretaceous Fruitland Formation, San Juan Basin, New Mexico: ABSTRACT

Huntite (CaMg{sub 3}(CO{sub 3}){sub 4}) is a metastable, ordered, double carbonate that was first described from Currant Creek, Nevada, in 1953. Since then, huntite has been described as a speleothemic carbonate in areas of magnesium-rich rocks and/or ground water; as a secondary weathering product in near-surface environments also in areas of magnesium-rich rocks (e.g., brucite, dolomite, serpentine, magnesite); as nodules in soils associated with deep weathering zones in dolomites and shales; and in a Holocene supratidal evaporite sequence along the Trucial Coast of the Persian Gulf. A continuous 304-ft core drilled in the Fruitland Formation of New Mexico has been sampled for various purposes, including clay and whole-rock mineralogy. X-ray diffraction analysis has clearly confirmed the presence of huntite at three levels: 33.9-34.7 ft; 80.3-81.0 ft; 132.6-141.6 ft. The huntite associations vary from lithographic carbonates to medium-grained silty sandstone. This is the first documented occurrence of huntite in other than Holocene deposits and requires modification of previously interpreted Fruitland paleoenvironments.

Applications of Fossil Resin Studies to an Understanding of Depositional and Paleoenvironments: ABSTRACT

Fossil resins are polymerized terpene (isoprenoid) acids. Because of their complexity and resulting variability, isoprenoids have been useful for their information content and geochemical signatures. Fossil resin occurs throughout a 304-ft continuous core and correlated outcrops from the Late Cretaceous Fruitland Formation in the Fossil Forest study area, San Juan basin, New Mexico, in associated with coal, sandstone, shale, and petrified wood. Fourier transformation infrared (FTIR) spectra of resin from throughout the sequence reveal oxidative and chemical variation. FTIR spectra of resin incorporated in petrified wood differ from those of resin exposed to the paleoatmosphere in the same individual tree. This study was initiated to complement previous studies related to analyses of fluid inclusions in fossil resin and to elucidate reactions between the resin matrix and possible atmospheric inclusions. It was done in conjunction with extensive trace-element, palynological, and mineralogical analyses. Understanding the biogeochemistry of fossil resin may elucidate the origin, diagenesis, and depositional environment of smaller concentrations of isoprenoids.

Upper Cretaceous Stratigraphy and Paleontology, Sevilleta Grant near La Joya, Socorro County, New Mexico: ABSTRACT

More than 1,300 ft (396 m) of Upper Cretaceous rocks overlies shales of the Upper Triassic Dockum Formation and are exposed on the Sevilleta Grant, near La Joya, Socorro County, New Mexico. The Upper Cretaceous sequence extends from the Dakota Sandstone to the Dilco Member of the Crevasse Canyon Formation and consists largely of shales and sandstones. The included Tres Hermanos Sandstone has been raised to formational status by Hook and Cobban and includes the lowermost Atarque Member, overlain by the Carthage Member and the Fite Ranch Member, respectively. The Atarque and Fite Ranch Members consist of sandstones; the Carthage Member consists of shales and sandstones and contains two coal beds. The Atarque Member is a moderately sorted, calcareous sandstone which coarsens upward with small- and medium- End_Page 554------------------------------ sized tangential, wedge and trough sets of cross-beds. The Atarque Member is about 11 ft (3.4 m) thick and contains fossil-rich lenses of poorly sorted, dark yellow-brown-weathering sands that are friable to moderately indurated and calcite cemented. Shale galls are present in the fossil-rich lenses and, with wood fragments, abundant turtle bone fragments, some crocodile tooth and scute fragments, amid vertebrae and teeth indicate a nearshore environment with a nearby source of fresh water. Selachian teeth and probable coprolites are richly varied and abundant. The following genera have been recognized: Hybodus, Lonchidion, Squalicorax, Squatina, Brachaelurus, Scapanorhynchus, Odontaspis, Cretoxyrhina, Cretolamna, Plicatolamna, Paranomotodon, Ischyrhiza, Ptychotrygon, Rhombodus, as we l as several as yet indeterminate genera. The dominant invertebrate genus is the oyster Crassostrea although at least two genera of gastropods are present. End_of_Article - Last_Page 555------------

Upper Cretaceous Stratigraphy and Paleontology, Lower Tres Hermanos Sandstone, Sevilleta Grant near La Joya, Socorro County, New Mexico: ABSTRACT

More than 1,300 ft (396 m) of Upper Cretaceous rocks overlie shales of the Upper Triassic Dockum Formation and are exposed on the Sevilleta Grant, near La Joya, Socorro County, New Mexico. The Upper Cretaceous sequence extends from the Dakota Sandstone to the Dilco Member of the Crevasse Canyon Formation and consists largely of shales and sandstones. The included Tres Hermanos Sandstone Member of the Mancos Shale includes sandstones, shales, and two coal beds. The lowermost sandstone unit is a moderately sorted, calcareous sandstone which coarsens upward and with small- and medium-scale tangential, wedge and trough-shaped sets of cross-beds. The sandstone is about 11 ft (3.4 m) thick and contains fossil-rich lenses of poorly sorted, dark yellow-brown-weathering sands that are friable to moderately indurated and calcite cemented. Shale galls are present in the fossil-rich lenses and, together with wood fragments, abundant turtle bone fragments, some crocodile tooth and scute fragments, amid vertebrae and teeth, indicate a nearshore environment with a nearby source of freshwater. Selachian teeth and probable coprolites are richly varied and abundant. The following genera have been recognized: Hybodus, Lonchidion, Squalicorax, Squatina, Bracha lurus, Scapanorhynchus, Odontaspis, Cretoxyrhina, Cretolamna, Plicatolamna, Paranomotodon, Ischyrhiza, Ptychotrygon, Rhombodus as well as several as yet indeterminate genera. The dominant invertebrate genus is the oyster Crassostrea soleniscus although at least two genera of gastropods are present. End_of_Article - Last_Page 554------------

Stratigraphy and Paleobotany of Lower Kirtland (Upper Cretaceous) Leaf Locality near Bisti, San Juan Basin, New Mexico: ABSTRACT

During a detailed stratigraphic study in the area of Hunter Wash, near Bisti, a new leaf locality was discovered in a sequence of mudstones, carbonaceous shales, siltstones, and sandstones. In the Bisti area, the boundary between the Fruitland and Kirtland formations is taken at the top of the highest carbonaceous shale above the highest Fruitland coal and below the prominent brown sandstone. The leaf locality lies within a 59-ft (18 m) measured section, about 14 ft (4.5 m) above the highest carbonaceous shale, within a gray-green shaly siltstone protected by an overlying sideritic concretion. Poorly preserved bivalves and gastropods are present in the deposit, but leaves predominate. Leaf collections contain the remains of ferns, conifers, and angiosperms; angiosperms dominate the assemblage. The most common angiospermous genera include Cercidiphyllum, Cissus, Ficus, Laurophyllum, Myrtophyllum, Platanus, Salix, and Rhamnus. Preliminary analysis of the collection has revealed that most of the angiospermous leaves are of medium size with entire, or nearly entire margins and drip points. These features indicate that during early Kirtland time, the climate of the area was warm-temperature to subtropical. End_of_Article - Last_Page 568------------