When Climate Ruled the Dinosaurs of Grand Staircase

Living in Geologic Time: Navigate the prolific boneyards and shifting boundaries of Grand Staircase-Escalante and Bears Ears National Monuments.

Recalibrating the Devonian time scale: A new method for integrating radioisotopic and astrochronologic ages in a Bayesian framework

The numerous biotic, climatic, and tectonic events of the Devonian cannot be correlated and investigated without a well-calibrated time scale. Here, we updated the calibration of the Devonian time scale using a Bayesian age-depth model that incorporates radioisotopic ages and astrochronology durations. We used existing radioisotopic ages collected and harmonized in the last two geologic time scale compilations, as well as new U-Pb zircon ages from Emsian {Hercules I K-bentonite, Wetteldorf, Germany: 394.290 ± 0.097(0.21)[0.47] Ma} and Eifelian K-bentonites {Tioga B and Tioga F K-bentonites, Fayette, New York, USA: 390.82 ± 0.18(0.26)[0.48] Ma and 390.14 ± 0.14(0.23)[0.47] Ma, respectively}. We anchored floating astrochronology stage durations on radioisotopic ages and chained astrochronologic constraints and uncertainty together to extrapolate conditioning age likelihoods up or down the geologic time scale, which is a new method for integrating astrochronology into age-depth modeling. The modeling results in similar ages and durations for Devonian stages regardless of starting biostratigraphic scaling assumptions. We produced a set of rescaled biostratigraphic zonations, and a new numerical calibration of Devonian stage boundary ages with robust uncertainty estimates, which allow us to evaluate future targets for Devonian time scale research. These methods are broadly applicable for time scale work and provide a template for an integrated stratigraphic approach to time scale modeling.

Evaluation of Boulder Deposits Linked to Late Neogene Hurricane Events

The Neogene is a globally recognized interval of geologic time that lasted from 23 until 1 [...]

Using relative geologic time to constrain CNN-based seismic interpretation and property estimation

Three-dimensional seismic interpretation and property estimation is essential to subsurface mapping and characterization, in which machine learning, particularly supervised convolutional neural network (CNN) has been extensively implemented for improved efficiency and accuracy in the past years. In most seismic applications, however, the amount of available expert annotations is often limited, which raises the risk of overfitting a CNN particularly when only seismic amplitudes are used for learning. In such a case, the trained CNN would have poor generalization capability, causing the interpretation and property results of obvious artifacts, limited lateral consistency and thus restricted application to following interpretation/modeling procedures. This study proposes addressing such an issue by using relative geologic time (RGT), which explicitly preserves the large-scale continuity of seismic patterns, to constrain a seismic interpretation and/or property estimation CNN. Such constrained learning is enforced in twofold: (1) from the perspective of input, the RGT is used as an additional feature channel besides seismic amplitude; and more innovatively (2) the CNN has two output branches, with one for matching the target interpretation or properties and the other for reconstructing the RGT. In addition is the use of multiplicative regularization to facilitate the simultaneous minimization of the target-matching loss and the RGT-reconstruction loss. The performance of such an RGT-constrained CNN is validated by two examples, including facies identification in the Parihaka dataset and property estimation in the F3 Netherlands dataset. Compared to those purely from seismic amplitudes, both the facies and property predictions with using the proposed RGT constraint demonstrate significantly reduced artifacts and improved lateral consistency throughout a seismic survey.

Windjamming on the Warming Gulf of Maine

Living in Geologic Time: A sailing venture reveals economic upheaval along Maine’s enduring coast.

Redwood National and State Parks: Geologic resources inventory report

Comprehensive park management to fulfill the NPS mission requires an accurate inventory of the geologic features of a park unit, but Comprehensive park management to fulfill the NPS mission requires an accurate inventory of the geologic features of a park unit, but park managers may not have the needed information, geologic expertise, or means to complete such an undertaking; therefore, the Geologic Resources Inventory (GRI) provides information and resources to help park managers make decisions for visitor safety, planning and protection of infrastructure, and preservation of natural and cultural resources. Information in the GRI report may also be useful for interpretation. park managers may not have the needed information, geologic expertise, or means to complete such an undertaking; therefore, the Geologic Resources Inventory (GRI) provides information and resources to help park managers make decisions for visitor safety, planning and protection of infrastructure, and preservation of natural and cultural resources. Information in the GRI report may also be useful for interpretation. This report synthesizes discussions from a scoping meeting for Redwood National and State Parks (referred to as the “parks” throughout this report) held in 2004 and a follow-up conference call in 2019. Two GRI–compiled GIS data sets of the geology and geohazards of the parks are the principal deliverables of the GRI. The GRI GIS data are available on the GRI publications website http://go.nps.gov/gripubs and through the NPS Integrated Resource Management Applications (IRMA) portal https://irma.nps.gov/App/Portal/Home. Enter “GRI” as the search text and select a park from the unit list. Writing of this report was based on those data and the interpretations of the source map authors (see “GRI Products” and “Acknowledgements”). A geologic map poster illustrates the geology GRI GIS data set and serves as a primary figure for this GRI report. No poster was prepared for the geohazards GRI GIS data set. Additionally, figure 7 of this report illustrates the locations of the major geologic features in the parks. Unlike the poster, which is divided into a northern and southern portion to show detail while accommodating the parks’ length, figure 7 is a single-page, simplified map. The features labeled on figure 7 are discussed in the “Geologic History, Features, and Processes” chapter. To provide a context of geologic time, this report includes a geologic time scale (see "Geologic History, Features, and Processes"). The parks’ geologic story encompasses 200 million years, starting in the Jurassic Period. Following geologic practice, the time scale is set up like a stratigraphic column, with the oldest units at the bottom and the youngest units at the top. Organized in this manner, the geologic time scale table shows the relative ages of the rock units that underlie the parks and the unconsolidated deposits that lie at the surface. Reading the “Geologic Event” column in the table, from bottom to top, will provide a chronologic order of the parks’ geologic history. The time scale includes only the map units within the parks that also appear on the geologic map poster; that is, map units of the geohazards data are not included. Geology is a complex science with many specialized terms. This report provides definitions of geologic terms at first mention, typically in parentheses following the term. Geologic units in the GRI GIS data are referenced in this report using map unit symbols; for example, map unit KJfrc stands for the Cretaceous (K) and Jurassic (J) Franciscan Complex (f), Redwood Creek schist (rc), which underlies a portion of the Redwood Creek watershed (see “GRI Products”).

Art about ancient life as a chronicle for the human condition

ABSTRACT Art about ancient life chronicles the human condition, less evidently but potentially as significantly, as it depicts life through geologic time. Selected examples surveyed here reveal human aspirations, values, conceits, sensibilities, and foibles and suggest that further in-depth study would be warranted. Greek bronzes embellished with griffins (625–575 B.C.E.) may represent ceratopsian fossils mythologized and commodified for their proximity to gold deposits. Encelius’ anthropomorphized drawing (1557) of a fossil bivalve exemplifies a conservative deference to outdated paradigms about nature; inversely, Nicolaus Steno prized geometry—then offering a new perspective on nature—and realized in 1667 that a drawing of “tongue stones” depicted not, as commonly held, simulacra of snake tongues molded by vital forces within the Earth but fossilized teeth of a once living shark; Beringer’s “lying stones” (1726) show how human conceit can bias the interpretation of “fossils.” Artworks since the mid-twentieth century record a growing recognition that ancient life and its habitats evolved together and therefore that art about ancient life has lessons for contemporary environmentalism: Rudolph Zallinger’s diachronous murals (mid-1940s) and the Milwaukee Public Museum’s diachronous dioramas (installed in 2001) display progressions of ancient and contemporary habitats; Alexis Rockman’s dystopian landscapes use ancient and extant life to critique human responsibility for degrading environments and endangering species. We conclude that studies of art about ancient life can deepen our understanding of the human condition and the cultural context in which it is created.