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Exploring: Palynology
Floristic and climatic reconstructions of two Lower Cretaceous successions from Peru
Climate during the Early Cretaceous in tropical South America has often been reconstructed as arid. However, some areas seem to have been humid. We reconstructed the floristic composition of two tropical stratigraphic successions in Peru using quantitative palynology (rarefied species richness and abundance), and used the abundance of aridity vs....
Geology along the Blue Ridge Parkway in Virginia
Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the...
Sedimentary petrology and reservoir quality of the Middle Jurassic Red Glacier Formation, Cook Inlet forearc basin: Initial impressions
The Division of Geological & Geophysical Surveys and Division of Oil & Gas are currently conducting a study of the hydrocarbon potential of Cook Inlet forearc basin (Gillis, 2013, 2014; LePain and others, 2013; Wartes, 2015; Herriott, 2016 [this volume]). The Middle Jurassic Tuxedni Group is recognized as a major source of oil in Tertiary...
Coastal and wetland ecosystems of the Chesapeake Bay watershed: Applying palynology to understand impacts of changing climate, sea level, and land use
The mid-Atlantic region and Chesapeake Bay watershed have been influenced by fluctuations in climate and sea level since the Cretaceous, and human alteration of the landscape began ~12,000 years ago, with greatest impacts since colonial times. Efforts to devise sustainable management strategies that maximize ecosystem services are integrating data...
Using simulated maps to interpret the geochemistry, formation and quality of the Blue Gem Coal Bed, Kentucky, USA
This study presents geostatistical simulations of coal-quality parameters, major oxides and trace metals for an area covering roughly 812 km2 of the Blue Gem coal bed in southeastern Kentucky, USA. The Blue Gem, characterized by low ash yield and low sulfur content, is an important economic resource. Past studies have characterized the Blue Gem's...
Laramide basin CSI: Comprehensive stratigraphic investigations of Paleogene sediments in the Colorado Headwaters Basin, north-central Colorado
The Paleogene sedimentary deposits of the Colorado Headwaters Basin provide a detailed proxy record of regional deformation and basin subsidence during the Laramide orogeny in north-central Colorado and southern Wyoming. This field trip presents extensive evidence from sedimentology, stratigraphy, structure, palynology, and isotope geochronology...
Palynological composition of a Lower Cretaceous South American tropical sequence: Climatic implications and diversity comparisons with other latitudes.
Premise of the study: Reconstruction of floristic patterns during the early diversification of angiosperms is impeded by the scarce fossil record, especially in tropical latitudes. Here we collected quantitative palynological data from a stratigraphic sequence in tropical South America to provide floristic and climatic insights into such tropical...
Response to critique by lucas et al. (2009) of paper by Fassett (2009) documenting Paleocene dinosaurs in the San Juan Basin
In this issue of Palaeontologia Electronica Lucas, et al. (2009) question the validity f the Fassett (2009) paper that presented evidence for Paleocene dinosaurs in the San Juan Basin of New Mexico and Colorado. Their challenges focus primarily on the lithostratigraphy, palynology, and paleomagnetism of the dinosaur-bearing Ojo Alamo Sandstone,...
A quarter-million years of paleoenvironmental change at Bear Lake, Utah and Idaho
A continuous, 120-m-long core (BL00-1) from Bear Lake, Utah and Idaho, contains evidence of hydrologic and environmental change over the last two glacial-interglacial cycles. The core was taken at 41.95??N, 111.31??W, near the depocenter of the 60-m-deep, spring-fed, alkaline lake, where carbonate-bearing sediment has accumulated continuously....
New geochronologic and stratigraphic evidence confirms the paleocene age of the dinosaur-bearing ojo alamo sandstone and animas formation in the San Juan Basin, New Mexico and Colorado
Dinosaur fossils are present in the Paleocene Ojo Alamo Sandstone and Animas Formation in the San Juan Basin, New Mexico, and Colorado. Evidence for the Paleo-cene age of the Ojo Alamo Sandstone includes palynologic and paleomagnetic data. Palynologic data indicate that the entire Ojo Alamo Sandstone, including the lower dinosaur-bearing part, is...
Tales from a distant swamp: Petrological and paleobotanical clues for the origin of the sand coal lithotype (Mississippian, Valley Fields, Virginia)
Tournasian (Mississippian) Price Formation semianthracites (Rmax = 2.40%) in the Valley Fields of southwestern Virginia contain a lithotype described in an early-20th-century report as a "sand" coal. The Center for Applied Energy Research inherited a collection of coals containing sand coal specimens, making it possible to study the lithotype from...
Lateral variation in geochemistry, petrology, and palynology in the Elswick coal bed, Pike County, Kentucky
The Middle Pennsylvanian/Langsettian (Westphalian A) Elswick coal bed, correlative to the Upper Banner of Virginia, is a rare example of a mined high-sulfur (> 2%) coal in Eastern Kentucky, a region known for low-sulfur coals. To characterize lateral variation in the geochemistry, petrography, and palynology of the Elswick coal bed, three sites...