The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central p... more The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central problem in human evolutionary studies. Australopithecus species differ markedly from extant African apes and candidate ancestral hominids such as Ardipithecus, Orrorin and Sahelanthropus. The earliest described Australopithecus species is Au. anamensis, the probable chronospecies ancestor of Au. afarensis. Here we describe newly discovered fossils from the Middle Awash study area that extend the known Au. anamensis range into northeastern Ethiopia. The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1-4.2 million years ago. They include diagnostic craniodental remains, the largest hominid canine yet recovered, and the earliest Australopithecus femur. These new fossils are sampled from a woodland context. Temporal and anatomical intermediacy between Ar. ramidus and Au. afarensis suggest a relatively rapid shift from Ardipithecus to Australopithecus in this region of Africa, involving either replacement or accelerated phyletic evolution.
Injection-induced seismicity became an important issue over the past decade, and although much of... more Injection-induced seismicity became an important issue over the past decade, and although much of the rise in seismicity is attributed to wastewater disposal, a growing number of cases have identified hydraulic fracturing (HF) as the cause. A recent study identified regions in Oklahoma where ≥75% of seismicity from 2010 to 2016 correlated with nearly 300 HF wells. To identify factors associated with increased probability of induced seismicity, we gathered publicly available information about the HF operations in these regions including: injected volume, number of wells on a pad, injected fluid (gel vs. slickwater), vertical depth of the well, proximity of the well to basement rock, and the formation into which the injection occurred. To determine the statistical strength of the trends, we applied logistic regression, bootstrapping, and odds ratios. We see no trend with total injected volume in our Oklahoma dataset, in contrast to strong trends observed in Alberta and Texas, but we n...
publication do not reflect official positions of the Society. regardless of their race, citizensh... more publication do not reflect official positions of the Society. regardless of their race, citizenship, gender, religion, or political viewpoint. Opinions presented in this provides this and other forums for the presentation of diverse opinions and positions by scientists worldwide, their organization's Web site providing the posting includes a reference to the article's full citation. GSA file may not be posted to any Web site, but authors may post the abstracts only of their articles on their own or copies of items in GSA's journals for noncommercial use in classrooms to further education and science. This use a single figure, a single table, and/or a brief paragraph of text in subsequent works and to make unlimited employment. Individual scientists are hereby granted permission, without fees or further requests to GSA, to Copyright not claimed on content prepared wholly by U.S. government employees within scope of their
clicking here. colleagues, clients, or customers by , you can order high-quality copies for your ... more clicking here. colleagues, clients, or customers by , you can order high-quality copies for your If you wish to distribute this article to others here. following the guidelines can be obtained by Permission to republish or repurpose articles or portions of articles ): January 13, 2011 www.sciencemag.org (this infomation is current as of The following resources related to this article are available online at http://www.sciencemag.org/content/331/6014/206.full.html version of this article at: including high-resolution figures, can be found in the online Updated information and services, http://www.sciencemag.org/content/suppl/2011/01/11/331.6014.206.DC1.html can be found at: Supporting Online Material http://www.sciencemag.org/content/331/6014/206.full.html#ref-list-1 , 3 of which can be accessed free: cites 24 articles This article http://www.sciencemag.org/cgi/collection/paleo Paleontology subject collections: This article appears in the following
The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics th... more The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years, as well as the contribution of uplift-related erosive flux to Cenozoic global cooling. The elevation history of the center and northern margin of the plateau have been historically less well-constrained than the southern margin. The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years, as well as the contribution of uplift-related erosive flux to Cenozoic global cooling. The elevation history of the center and northern margin of the plateau have been historically less well-constrained than the southern margin. A diverse suite of techniques, each with their own biases and uncertainties, yield discrepant mid-Cenozoic elevation estimates (0–5 km). We reconstruct Paleogene to Miocene elevations of the Lunpola basin on the northern Lhasa terrane, the southernmost crustal block of the Tibetan Plateau, using stable isotope paleoaltimetry and clumped-isotope paleothermometry on lacustrine and pedogenic carbonates, integrated with previously published compound-specific n-alkane-derived hydrogen isotopes. Paleo-elevation estimates for the Lunpola basin (∼3.1–4.7 km) demonstrate that the northern edge of the Lhasa Block attained high elevation prior to ∼24 Ma and potentially by the Early Eocene (<48 Ma). Our results allow for the possibility that the entire Lhasa Block was composed of extremely thick continental crust at the initiation of India-Asia collision, rather than restricting the extent of thick crust to the Linzizong volcanic arc (“Lhasaplano” model) or Gangdese Mountains, and also refutes studies invoking a low elevation interpretation based on higher oxygen and compound-specific δD isotope values. Better constraints on depositional ages in the Lunpola basin are needed to refine the early Cenozoic elevation history along the Bangong-Nujiang suture zone. Finally, we posit that interpretations of proxy data can be biased by incomplete or selective sampling, and propose multi-proxy, intrinsically cross-disciplinary studies to resolve inconsistent interpretations from otherwise unrelated proxies.
This open-file report was prepared by the authors under contract to the Utah Department of Natura... more This open-file report was prepared by the authors under contract to the Utah Department of Natural Resources, Utah Geological Survey. The report has not undergone the full UGS review process, and may not necessarily conform to UGS technical, editorial, or policy standards. Therefore, it may be premature for an individual or group to take action based on its content.
A collaborative bedrock/surficial deposit mapping project between Miami University and the Ohio D... more A collaborative bedrock/surficial deposit mapping project between Miami University and the Ohio Department of Natural Resources (ODNR), Division of Geological Survey has resulted in the generation of a revised bedrock topography map for the Oxford and College Corner 7.5-minute quadrangles, Butler and Preble counties, southwest Ohio. The study area consists of glaciated uplands dissected by filled valleys of the Indian Creek, Four-Mile Creek, and Seven-Mile Creek drainages. Late Wisconsinan-age moraine, outwash, and lacustrine deposits overlie Ordovician-Silurian sedimentary bedrock and range in thickness from 0 to >200 ft. As all subsurface geological units in the study area to some extent serve as residential, agricultural, industrial, and municipal aquifers, more accurately delineating the extent of these resources was the primary motivation of the study. Building on mapping conducted by ODRN in the 1990s, the present study utilized water-well and borehole log data available on-line through the ODNR Division of Water Resources and the Ohio Department of Transportation. Additional Quaternary thickness and depth-to-bedrock data were derived from municipal water-supply and monitoring well logs drilled by the City of Oxford and Miami University. The study also incorporated field mapping of exposures of the Quaternary-Paleozoic contact as well as horizontal-to-vertical spectral ratio (HVSR) passive seismic analysis. HVSR data were calibrated at recording stations adjacent to wells with bedrock penetrations. Study results generated over 950 individual elevation points of the Quaternary-Paleozoic contact, more than 3x the number used in earlier mapping efforts. The resulting higher resolution contour map of the bedrock topography indicates valley-fill deposits in some parts of the study area are narrower but deeper than previously mapped, and thus likely contain steeper basal contacts with underlying Paleozoic rocks. As valley-fill deposits serve as on the primary municipal aquifers in the study area, these findings may have important implications for the future development and utilization of local groundwater resources.
The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central p... more The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central problem in human evolutionary studies. Australopithecus species differ markedly from extant African apes and candidate ancestral hominids such as Ardipithecus, Orrorin and Sahelanthropus. The earliest described Australopithecus species is Au. anamensis, the probable chronospecies ancestor of Au. afarensis. Here we describe newly discovered fossils from the Middle Awash study area that extend the known Au. anamensis range into northeastern Ethiopia. The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1-4.2 million years ago. They include diagnostic craniodental remains, the largest hominid canine yet recovered, and the earliest Australopithecus femur. These new fossils are sampled from a woodland context. Temporal and anatomical intermediacy between Ar. ramidus and Au. afarensis suggest a relatively rapid shift from Ardipithecus to Australopithecus in this region of Africa, involving either replacement or accelerated phyletic evolution.
Injection-induced seismicity became an important issue over the past decade, and although much of... more Injection-induced seismicity became an important issue over the past decade, and although much of the rise in seismicity is attributed to wastewater disposal, a growing number of cases have identified hydraulic fracturing (HF) as the cause. A recent study identified regions in Oklahoma where ≥75% of seismicity from 2010 to 2016 correlated with nearly 300 HF wells. To identify factors associated with increased probability of induced seismicity, we gathered publicly available information about the HF operations in these regions including: injected volume, number of wells on a pad, injected fluid (gel vs. slickwater), vertical depth of the well, proximity of the well to basement rock, and the formation into which the injection occurred. To determine the statistical strength of the trends, we applied logistic regression, bootstrapping, and odds ratios. We see no trend with total injected volume in our Oklahoma dataset, in contrast to strong trends observed in Alberta and Texas, but we n...
publication do not reflect official positions of the Society. regardless of their race, citizensh... more publication do not reflect official positions of the Society. regardless of their race, citizenship, gender, religion, or political viewpoint. Opinions presented in this provides this and other forums for the presentation of diverse opinions and positions by scientists worldwide, their organization's Web site providing the posting includes a reference to the article's full citation. GSA file may not be posted to any Web site, but authors may post the abstracts only of their articles on their own or copies of items in GSA's journals for noncommercial use in classrooms to further education and science. This use a single figure, a single table, and/or a brief paragraph of text in subsequent works and to make unlimited employment. Individual scientists are hereby granted permission, without fees or further requests to GSA, to Copyright not claimed on content prepared wholly by U.S. government employees within scope of their
clicking here. colleagues, clients, or customers by , you can order high-quality copies for your ... more clicking here. colleagues, clients, or customers by , you can order high-quality copies for your If you wish to distribute this article to others here. following the guidelines can be obtained by Permission to republish or repurpose articles or portions of articles ): January 13, 2011 www.sciencemag.org (this infomation is current as of The following resources related to this article are available online at http://www.sciencemag.org/content/331/6014/206.full.html version of this article at: including high-resolution figures, can be found in the online Updated information and services, http://www.sciencemag.org/content/suppl/2011/01/11/331.6014.206.DC1.html can be found at: Supporting Online Material http://www.sciencemag.org/content/331/6014/206.full.html#ref-list-1 , 3 of which can be accessed free: cites 24 articles This article http://www.sciencemag.org/cgi/collection/paleo Paleontology subject collections: This article appears in the following
The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics th... more The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years, as well as the contribution of uplift-related erosive flux to Cenozoic global cooling. The elevation history of the center and northern margin of the plateau have been historically less well-constrained than the southern margin. The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years, as well as the contribution of uplift-related erosive flux to Cenozoic global cooling. The elevation history of the center and northern margin of the plateau have been historically less well-constrained than the southern margin. A diverse suite of techniques, each with their own biases and uncertainties, yield discrepant mid-Cenozoic elevation estimates (0–5 km). We reconstruct Paleogene to Miocene elevations of the Lunpola basin on the northern Lhasa terrane, the southernmost crustal block of the Tibetan Plateau, using stable isotope paleoaltimetry and clumped-isotope paleothermometry on lacustrine and pedogenic carbonates, integrated with previously published compound-specific n-alkane-derived hydrogen isotopes. Paleo-elevation estimates for the Lunpola basin (∼3.1–4.7 km) demonstrate that the northern edge of the Lhasa Block attained high elevation prior to ∼24 Ma and potentially by the Early Eocene (<48 Ma). Our results allow for the possibility that the entire Lhasa Block was composed of extremely thick continental crust at the initiation of India-Asia collision, rather than restricting the extent of thick crust to the Linzizong volcanic arc (“Lhasaplano” model) or Gangdese Mountains, and also refutes studies invoking a low elevation interpretation based on higher oxygen and compound-specific δD isotope values. Better constraints on depositional ages in the Lunpola basin are needed to refine the early Cenozoic elevation history along the Bangong-Nujiang suture zone. Finally, we posit that interpretations of proxy data can be biased by incomplete or selective sampling, and propose multi-proxy, intrinsically cross-disciplinary studies to resolve inconsistent interpretations from otherwise unrelated proxies.
This open-file report was prepared by the authors under contract to the Utah Department of Natura... more This open-file report was prepared by the authors under contract to the Utah Department of Natural Resources, Utah Geological Survey. The report has not undergone the full UGS review process, and may not necessarily conform to UGS technical, editorial, or policy standards. Therefore, it may be premature for an individual or group to take action based on its content.
A collaborative bedrock/surficial deposit mapping project between Miami University and the Ohio D... more A collaborative bedrock/surficial deposit mapping project between Miami University and the Ohio Department of Natural Resources (ODNR), Division of Geological Survey has resulted in the generation of a revised bedrock topography map for the Oxford and College Corner 7.5-minute quadrangles, Butler and Preble counties, southwest Ohio. The study area consists of glaciated uplands dissected by filled valleys of the Indian Creek, Four-Mile Creek, and Seven-Mile Creek drainages. Late Wisconsinan-age moraine, outwash, and lacustrine deposits overlie Ordovician-Silurian sedimentary bedrock and range in thickness from 0 to >200 ft. As all subsurface geological units in the study area to some extent serve as residential, agricultural, industrial, and municipal aquifers, more accurately delineating the extent of these resources was the primary motivation of the study. Building on mapping conducted by ODRN in the 1990s, the present study utilized water-well and borehole log data available on-line through the ODNR Division of Water Resources and the Ohio Department of Transportation. Additional Quaternary thickness and depth-to-bedrock data were derived from municipal water-supply and monitoring well logs drilled by the City of Oxford and Miami University. The study also incorporated field mapping of exposures of the Quaternary-Paleozoic contact as well as horizontal-to-vertical spectral ratio (HVSR) passive seismic analysis. HVSR data were calibrated at recording stations adjacent to wells with bedrock penetrations. Study results generated over 950 individual elevation points of the Quaternary-Paleozoic contact, more than 3x the number used in earlier mapping efforts. The resulting higher resolution contour map of the bedrock topography indicates valley-fill deposits in some parts of the study area are narrower but deeper than previously mapped, and thus likely contain steeper basal contacts with underlying Paleozoic rocks. As valley-fill deposits serve as on the primary municipal aquifers in the study area, these findings may have important implications for the future development and utilization of local groundwater resources.
Uploads
Papers by Brian Currie