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Abrupt quaternary ocean-ice events in the Arctic: Evidence from the ostracode rabilimis

The Arctic Ocean has experienced orbital and millennial-scale climate oscillations over the last 500 kilo-annum (ka) involving massive changes in global sea level and components of the Arctic cryosphere, including sea-ice cover, land-based ice sheets and ice shelves. Although these climate events are only partially understood, micropaleontological studies utilizing ostracodes and benthic foraminif
Authors
Thomas M. Cronin, Laura Gemery, Baylee M. Olds Olds, Alexa Regnier, Robert Poirier, Sienna Sui

Identification of thermal maturity-relevant organic matter in Shale Working Group Report 2021

The Identification of Thermal Maturity-Relevant Organic Matter in Shale Working Group of the ICCP was established in 2008 to provide guidelines for identifying and measuring the reflectance of the population of dispersed organic matter that is relevant to thermal maturity determination. Information products published by the working group include ASTM D7708 Standard Test Method for Microscopical De
Authors
Paul C. Hackley, Javin J. Hatcherian, Jennifer L. Rivera, Margaret M. Sanders, Brett J. Valentine

Melt surges, flow differentiation, and remobilization of crystal-rich mushes in response to unloading: Observations from Kīlauea Iki lava lake, Hawaii

Field and laboratory studies of the 1959 Kīlauea Iki lava lake have provided insight into differentiation processes in mafic magma chambers. This paper explores how partially molten basaltic mushes responded to unloading as a consequence of drilling. Most holes drilled from 1967 to 1979 terminated in a melt-rich internal differentiate with a sharp crust-melt interface. These interfaces were not st
Authors
Rosalind L. Helz

Surface ocean warming and acidification driven by rapid carbon release precedes Paleocene-Eocene Thermal Maximum

The Paleocene-Eocene Thermal Maximum (PETM) is recognized by a major negative carbon isotope (δ13C) excursion (CIE) signifying an injection of isotopically light carbon into exogenic reservoirs, the mass, source, and tempo of which continue to be debated. Evidence of a transient precursor carbon release(s) has been identified in a few localities, although it remains equivocal whether there is a gl
Authors
Tali L. Babila, Don E Penman, CD Standish, Monica Doubrawa, Tim J Bralower, Marci M. Robinson, Jean Self-Trail, Robert P. Speijer, Peter Stassen, Gavin L Foster, James C. Zachos

Past terrestrial hydroclimate sensitivity controlled by Earth system feedbacks

Despite tectonic conditions and atmospheric CO2 levels (pCO2) similar to those of present-day, geological reconstructions from the mid-Pliocene (3.3-3.0 Ma) document high lake levels in the Sahel and mesic conditions in subtropical Eurasia, suggesting drastic reorganizations of subtropical terrestrial hydroclimate during this interval. Here, using a compilation of proxy data and multi-model paleoc
Authors
R. Feng, T. Bhattacharya, B. Otto-Bliesner, E. Brady, A. M. Haywood, J. Tindall, S. J. Hunter, A. Abe- Ouchi, W.-L. Chan, M. Kageyama, C. Contoux, C. Guo, X. Li, G. Lohmann, C. Stepanek, N. Tan, Q. Zhang, Z. Zhang, Z. Han, J.R. Williams, D. J. Lunt, Harry J. Dowsett, Deepak Chandan, W. Richard Peltier

Preliminary geologic map of the Cherry Hill quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia

The Cherry Hill 7.5-minute quadrangle straddles the Coastal Plain and Piedmont Provinces along the Tidewater Fall Line. Rocks of the eastern Piedmont Roanoke Rapids terrane crop out in the western part of the quadrangle and consist of greenschist- to amphibolite-facies Neoproterozoic felsic to intermediate metavolcanic rocks, some of which contain flattened quartz phenocrysts and are locally isocl
Authors
Mark W. Carter, Adam T. Karst, C. Rick Berquist, J. Stephen Schindler, Robert E. Weems, Benjamin R. Weinmann, E. Allen Crider, Jr.

The Anthropocene as an event, not an epoch

Over the course of the last decade the concept of the Anthropocene has become widely established within and beyond the geoscientific literature but its boundaries remain undefined. Formal definition of the Anthropocene as a chronostratigraphical series and geochronological epoch following the Holocene, at a fixed horizon and with a precise global start date, has been proposed, but fails to account
Authors
Philip Gibbard, Michael J.C. Walker, Andrew M Bauer, Matthew Edgeworth, Lucy E. Edwards, Erle C Ellis, Stanley C. Finney, Jacqueline L Gill, Mark Maslin, Dorothy Merritts, William F Ruddiman

Shallow faulting and folding in the epicentral area of the 1886 Charleston, South Carolina, earthquake

The moment magnitude (⁠Mw�w⁠) ∼7 earthquake that struck Charleston, South Carolina, on 31 August 1886 is the largest historical earthquake in the United States east of the Appalachian Mountains. The fault(s) that ruptured during this earthquake has never been conclusively identified, and conflicting fault models have been proposed. Here we interpret reprocessed seismic reflection profiles, reproce
Authors
Thomas L. Pratt, Anjana K. Shah, R.C Counts, J. Wright Horton,, M.C. Chapman

Power analysis for detecting the effects of best management practices on reducing nitrogen and phosphorus fluxes to the Chesapeake Bay watershed, USA

In 2010 the U.S. Environmental Protection Agency established the Total Maximum Daily Load (TMDL) which is a “pollution diet” that aims to reduce the amount of nitrogen and phosphorus entering the Chesapeake Bay, the largest estuary in the United States, by 25 and 24% percent, respectively. To achieve this goal the TMDL requires the implementation of Best Management Practices (BMPs), which are acce
Authors
Paul McLaughlin, Richard Alexander, Joel Blomquist, Olivia H. Devereux, Gregory B. Noe, Kelly L. Smalling, Tyler Wagner

Geology & mineralogy of the Old Mine Park area Trumbull Connecticut

Old Mine Park, in the northern Trumbull area (also known as Long Hill) of southwestern Connecticut, is a recreation area encompassing the mineral-rich hill of “Saganawamps” and owned by the Town of Trumbull. Most of its 72 acres are wooded, rocky and undeveloped but it is surrounded by dense infrastructure and transportation, residential, retail, and commercial development (Figure 1). It preserves
Authors
Harold Moritz, Robert P. Wintsch, Bill Devlin, Ryan J. McAleer, Shinae Lee, SookJu Kim, Keewook Yi

An apparent dip calculator for spreadsheets

This report and spreadsheet calculator contain Microsoft Excel-based equations that are useful in structural geology to calculate plunge or apparent dip when measuring lineations on a plane. The spreadsheet allows users to measure the trend or the plunge of a lineation and calculate the corresponding unknown value of trend or plunge. The spreadsheet provides the user with two options:Option 1: Cal
Authors
Gregory J. Walsh

Lessons learned from 20 y of monitoring suburban development with distributed stormwater management in Clarksburg, Maryland, USA

Urban development is a well-known stressor for stream ecosystems, presenting a challenge to managers tasked with mitigating its effects. For the past 20 y, streamflow, water quality, geomorphology, and benthic communities were monitored in 5 watersheds in Montgomery County, Maryland, USA. This study presents a synthesis of multiple studies of monitoring efforts in the study area and new analysis o
Authors
Kristina G. Hopkins, Sean Woznicki, Brianna Williams, Charles C. Stillwell, Eric Naibert, Marina Metes, Daniel Jones, Dianna M. Hogan, Natalie Celeste Hall, Rosemary M. Fanelli, Aditi S. Bhaskar