Karla Parsons-hubbard - Academia.edu (original) (raw)
Papers by Karla Parsons-hubbard
AGUFM, Dec 1, 2007
The Pierre Shale in Colorado hosts an extensive fault-controlled network of Late Cretaceous fossi... more The Pierre Shale in Colorado hosts an extensive fault-controlled network of Late Cretaceous fossil-rich carbonate accumulations expressed topographically as the Teepee Buttes. An ancient methane seep origin for these features is clear from carbonate-carbon isotope values that are as light as -50 per mil and from organic biomakers that point to abundant aerobic and anaerobic methanotrophy. A primary goal is to identify the patterns of sulfate reduction linked to anaerobic oxidation of methane (and other possible hydrocarbons) through a detailed isotopic study of sulfur preserved as carbonate-associated sulfate trapped within authigenic and biogenic phases. We are further constraining these patterns by calibrating them against our studies of modern seeps in the Gulf of Mexico. Delineating micro- and macrofaunal symbiotic linkages driven by chemosynthetic (sulfide-oxidizing) bacterial communities is a related goal. Through ongoing analysis of shell material, we hope to fingerprint thiotrophic activity within specific organisms, including lucinid bivalves. Consistent with the abundant benthic macrofauna, C- S-Fe analysis of the host shales indicates that bottom waters were oxygenated at the time of seep activity. Our work expands on previous studies to include a detailed paragenesis of the carbonate fabrics, which is aided by high-resolution C isotope and trace element analysis. Our results show that early-formed carbonates are characterized by depleted C isotope values, comparatively heavy O, low Fe contents, and high Sr and Mg. Late carbonates show isotope and elemental relationships that are generally opposite those of the early precipitates. Botryoidal cements, pelsparites, and yellow calcite dominate the early diagenetic forms. Blocky white sparry cements formed later, and micrite is mostly a product of later micritization of early fabrics and correspondingly shows broad geochemical properties. The overarching focus of all this work is to understand the timing, location (surface vs. subsurface), mechanisms, and specific microbial factors behind carbonate authigenesis and their relationships to macrofaunal ecology.
PALAIOS, 2002
The Shelf and Slope Experimental Taphonomy Initiative (SSETI) Program was established to measure ... more The Shelf and Slope Experimental Taphonomy Initiative (SSETI) Program was established to measure taphonomic rates in a range of continental shelf and slope environments. Experiments were deployed on the forereef slope off Lee Stocking Island, Bahamas, for one and two ...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2002
The Shelf and Slope Experimental Taphonomy Initiative was established to measure taphonomic rates... more The Shelf and Slope Experimental Taphonomy Initiative was established to measure taphonomic rates in a range of continental shelf and slope environments of deposition (EODs) over a multiyear period. We deployed experiments on the forereef slope off Lee Stocking Island, Bahamas, and on the continental shelf and slope of the Gulf of Mexico for 2 yr in 18 distinctive EODs at depths from 15 to 530 m. Overall, most shells deployed at most sites had relatively minor changes in shell condition. Most EODs generated relatively similar taphonomic signatures. A few sites did produce taphonomic signatures clearly distinguishable from the central group and these sites were characterized by one or more of the following: high rates of oxidation of reduced compounds, presence in the photic zone, and significant burial and exhumation events. Thus, unique taphonomic signatures are created by unique combinations of environmental conditions that include variables associated with regional gradients, such as depth and light, and variables associated with edaphic processes, such as the seepage of brine or petroleum or the resuspension and redeposition of sediment. Most sites, however, showed similar taphonomic signatures, despite the variety of EOD characteristics present, suggesting that insufficient time had elapsed over 2 yr to generate a more diverse array of taphonomic signatures. Discoloration and dissolution were by far the dominant processes over the 2-yr deployment period. Periostracum breakdown, loss of shell weight, and chipping and breakage was less noticeable. EODs were chosen based on the expectation that the process of burial and the influence of depth and sediment type should play the greatest roles in determining between-EOD differences in taphonomic signature. EOD-specific edaphic factors often overrode the influence of geographic-scale environmental gradients. Taphonomic alteration was greater on
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Bivalve shells deployed experimentally in a variety of environments of deposition (EODs) and over... more Bivalve shells deployed experimentally in a variety of environments of deposition (EODs) and over a wide range of depths from 15 to 570 m in the Bahamas and Gulf of Mexico were assessed for encrusting and endolithic bionts (sclerobionts sensu Taylor and Wilson, 2002) that accumulated over 1-, 2-, 8-and 12/13year intervals. Data include percent coverage and, when possible, identification to generic-or species-level taxonomic categories. Data were binned into two further categories based on guilds and whether or not sclerobionts were judged to be preservable. Each study site shows substantial variability in both percent coverage and species richness/composition, which we attribute to partial burial of different individuals or parts of arrays. Average values of taxonomic richness, guild number, and percent coverage, for a given EOD represent a combination of exposed and buried shells as would be typical of a time-averaged fossil assemblage; maximally covered shells give the potential coverage for each site. In both study areas there are characteristic patterns in terms of overall percentage of shells covered by sclerobionts, numbers and extent of coverage by different guilds as well as by different taxa. For most EODs, there is a progressive, though non-linear increase in both species richness and areal coverage through the twelve years; exceptions are in the 30 m site in the Bahamas, and Parker Bank and Flower Garden sites in the Gulf of Mexico, which show a significant decline in areal coverage (though not in richness). This effect may result from differences in sediment cover over time. These sites showed a tendency to have many or all experimental bags completely sediment covered in the later sampling. Cluster analysis and non-metric multidimensional scaling (NMDS) of various shell substrate species at all EODs from the Bahamas and Gulf of Mexico reveal discrete groupings that are related to both depth (light?) gradient and other factors, such as variations in sedimentation and salinity. Similar numbers of guilds are found at various EODs although the specific guild types represented differ. In general, highest average richness values are recorded for carbonate 70-90 m wall and deep reef sites (69 to 70 taxa) and lowest are for the EFG brine pool (no sclerobionts other than bacterial films after 12/13 years) and deeper dysphotic to subphotic sites (max values: 25 taxa); surprisingly, shallow water sites (b 30 m) yield only moderate diversities of 40-50 taxa. This results in part from the fact that certain encrusters, especially the foraminifer Gypsina and coralline algae tend to overgrow others and dominate space, in addition to burial effects. Certain taxa (notably the serpulid Pseudovermilia) are ubiquitous, while other taxa (e.g. larger foraminifera, vermetid gastropods and many bryozoans) are largely restricted to shallower depths. A combination of species richness, average coverage and key taxa permits discrimination of groups of EODs and potentially, in tandem with other evidence, of depth gradients.
The Paleontological Society Special Publications, 1992
Patterns of epibiont coverage are potentially useful tools in the determination of modern and anc... more Patterns of epibiont coverage are potentially useful tools in the determination of modern and ancient sedimentation rates as well as life habits of host organisms. A study was conducted to characterize patterns of epibiont settlement in various tropical environments and substrate types. Settling plates of clean aragonite shell were placed in six carbonate environments (beach, grass bed, bioturbated sand flat, back reef, forereef, and muddy bay) on St. Croix to document successional trends and timing of infestation by preservable, calcareous epibionts. Coralline algae were first to settle on freshly exposed substrate (within one week), followed by the foraminiferan Planorbulina and serpulid/spirorbid worm tubes. This successional order of epibiont encrustation is proposed as a measure of the length of time a shell has been exposed.The results of this experiment were compared to epibiont patterns on naturally occurring substrates from the same environments. Because the study areas wer...
Geological Society of America Abstracts with Programs
Earth and Life, 2012
The concept of sclerobiofacies is defined herein as suites of sclerobiont encrusters and endiont ... more The concept of sclerobiofacies is defined herein as suites of sclerobiont encrusters and endiont borers (collectively sclerobionts) preserved on skeletons that characterize particular facies/environments. Skeletal components provide biologically standardized substrates; when possible, comparison of encrusting assemblages on fossil shells of the same or closely related eurytopic species provides a degree of substrate control comparable to modern experimentally deployed shells. Taxonomic composition of sclerobiont suites varies rather predictably among marine environments (e.g., based upon depth) but is primarily useful for comparisons of environments within local areas and limited time frames. Parameters that may be used to compare sclerobiofacies across broader spatial and temporal dimensions include: per shell and cumulative species richness (diversity), frequency of encrustation, areal coverage, and guild structure of encrusting taxa. Herein, we summarize characteristic sclerobiofacies in a series of Recent and ancient examples. Modern subtropical marine encrusters, documented on experimentally deployed molluscan shells at sites ranging from 15 to over 200 m, show high biont richness in shallow subtidal areas. Maximal areal coverages in Bahamian samples occur at about 20–30 m, whereas species richness increases downward to the deeper euphotic zone (∼75–80 m). Below this level, rapid decline in both richness and percent coverage results in deeper Dysphotic–Aphotic zone samples yielding only a few species with coverage rarely exceeding 5%. Burial is also a key factor such that rapidly buried shells in the Shallow Euphotic zone have species coverages, richnesses, and taxonomic compositions resembling long-exposed shells in deeper areas below the euphotic zone. Shelly substrates from the Cambrian to Early Ordovician exhibit only minor encrustation by solitary attached taxa, especially echinoderms; however, by the Late Ordovician various solitary (e.g., cornulitids, craniid brachiopods) and colonial forms (e.g., trepostome and tubuliporate bryozoans) form distinctive sclerobiofacies. Photic zone-related environments, judged independently on the basis of microendoliths, show overall lower taxonomic richness than modern counterparts. However, they also show common patterns, including a general decrease of richness and percent encrustation from Shallow Euphotic to Dysphotic/Aphotic zones. Comparable trends are seen in Middle Devonian exemplars from New York State. Not only were there consistent trends toward lowered diversity/coverage into deep-water settings but also an additional factor related to turbidity and/or sedimentation rate was identified from assemblages at comparable depths arrayed along a distal to proximal gradient with respect to siliciclastic input sources. Carboniferous sclerobiont suites from varied sites in North America show many of the same traits as their Devonian counterparts, although detailed depth zonations are not documented at present. The Permo-Triassic extinctions appear to have had a strong impact on the taxonomic composition of marine sclerobiofacies, although a paucity of studies obscures details of Mesozoic and Cenozoic sclerobiofacies. In general, they appear to have taxonomic compositions and patterns similar to those observed in the Recent. The concept of sclerobiofacies provides another tool for paleoenvironmental analysis. Together with litho-, ichno-, bio-, and taphofacies, the properties of shell encrusting assemblages will yield detailed further insights into ancient environmental gradients.
Journal of Shellfish Research, 2008
... The effects of sulfide and an increased food supply on the meiofauna and macrofauna at the Ea... more ... The effects of sulfide and an increased food supply on the meiofauna and macrofauna at the East Flower Garden brine seep. Helgol. Meeresunters 40:5782. CrossRef. Powell, EN, KM Parsons-Hubbard, WR Callender, GM Staff, GT Rowe, CE Brett, SE Walker, A. Raymond, DD ...
PALAIOS, 2002
... Predation on Experimentally Deployed Molluscan Shells from Shelf to Slope Depths in a Tropica... more ... Predation on Experimentally Deployed Molluscan Shells from Shelf to Slope Depths in a Tropical Carbonate Environment. SALLY E. WALKER 1 , KARLA PARSONS-HUBBARD 2 , ERIC POWELL 3 and CARLTON E. BRETT 4 ...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
We utilize information from a suite of molluscan species deployed in a variety of Caribbean and G... more We utilize information from a suite of molluscan species deployed in a variety of Caribbean and Gulf of Mexico environments of preservation (EOP) by SSETI (Shelf and Slope Experimental Taphonomy Initiative) to examine to what degree interpretation of the ...
Earth and Planetary Science Letters, 2006
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
In this paper, we will discuss a two-week experiential learning trip to Indonesia, ranging from t... more In this paper, we will discuss a two-week experiential learning trip to Indonesia, ranging from the design phase to a module course and in-country implementation with two institutional partners in country. The trip involved four faculty and eight students from disciplines ranging from Geology, Anthropology, Environmental Studies to Chemistry and Music. Comparison was at the heart of the project. Our team explored the cultural and functional responses to the 2004 tsunami in Banda Aceh and volcanic eruptions of Mount Merapi in Central Java. Contrasting views of cause and recovery proved especially enlightening. Acehnese responses were tightly woven with immediate pre-tsunami political upheaval along with Islamic framings of the disaster. In comparison, we found responses to volcanic eruptions on Java were quite different because the community affected was more multicultural. We will pepper our account of this pedagogical experience with personal outcomes, cultural interactions, and th...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Palaios, 2008
Examination of remains of Callinectes sapidus deployed in several depth and environmental setting... more Examination of remains of Callinectes sapidus deployed in several depth and environmental settings in the Bahamas and Gulf of Mexico as part of the Shelf and Slope Experimental Taphonomy Initiative project revealed that all specimens were uniformly and strongly de- graded except those in brine-seep settings. Fragmentation and loss of cuticular material at all sites was correlated to the degree
Geology, 1992
... Some studies suggest that storm-induced skeletal transport can be substantial (eg, Westrop, 1... more ... Some studies suggest that storm-induced skeletal transport can be substantial (eg, Westrop, 1986). ... the south seagrass bed, whereas samples from the north seagrass bed were grouped in cluster 4. There were two out-liers: sample 1020, from the back reef, and sam-ple 630 ...
... 1 Department of Geology, Oberlin College, Oberlin, OH 44074, Karla.hubbard{at}oberlin.edu. ..... more ... 1 Department of Geology, Oberlin College, Oberlin, OH 44074, Karla.hubbard{at}oberlin.edu. ... Examples include near-shore carbonate or mixed carbonate/ terrigenous facies (Pilkey et al., 1979; Parsons, 1989; Dent, 1996; Best and Kidwell, 2000a,b; Kidwell et al., 2001), tidal-flat ...
AGUFM, Dec 1, 2007
The Pierre Shale in Colorado hosts an extensive fault-controlled network of Late Cretaceous fossi... more The Pierre Shale in Colorado hosts an extensive fault-controlled network of Late Cretaceous fossil-rich carbonate accumulations expressed topographically as the Teepee Buttes. An ancient methane seep origin for these features is clear from carbonate-carbon isotope values that are as light as -50 per mil and from organic biomakers that point to abundant aerobic and anaerobic methanotrophy. A primary goal is to identify the patterns of sulfate reduction linked to anaerobic oxidation of methane (and other possible hydrocarbons) through a detailed isotopic study of sulfur preserved as carbonate-associated sulfate trapped within authigenic and biogenic phases. We are further constraining these patterns by calibrating them against our studies of modern seeps in the Gulf of Mexico. Delineating micro- and macrofaunal symbiotic linkages driven by chemosynthetic (sulfide-oxidizing) bacterial communities is a related goal. Through ongoing analysis of shell material, we hope to fingerprint thiotrophic activity within specific organisms, including lucinid bivalves. Consistent with the abundant benthic macrofauna, C- S-Fe analysis of the host shales indicates that bottom waters were oxygenated at the time of seep activity. Our work expands on previous studies to include a detailed paragenesis of the carbonate fabrics, which is aided by high-resolution C isotope and trace element analysis. Our results show that early-formed carbonates are characterized by depleted C isotope values, comparatively heavy O, low Fe contents, and high Sr and Mg. Late carbonates show isotope and elemental relationships that are generally opposite those of the early precipitates. Botryoidal cements, pelsparites, and yellow calcite dominate the early diagenetic forms. Blocky white sparry cements formed later, and micrite is mostly a product of later micritization of early fabrics and correspondingly shows broad geochemical properties. The overarching focus of all this work is to understand the timing, location (surface vs. subsurface), mechanisms, and specific microbial factors behind carbonate authigenesis and their relationships to macrofaunal ecology.
PALAIOS, 2002
The Shelf and Slope Experimental Taphonomy Initiative (SSETI) Program was established to measure ... more The Shelf and Slope Experimental Taphonomy Initiative (SSETI) Program was established to measure taphonomic rates in a range of continental shelf and slope environments. Experiments were deployed on the forereef slope off Lee Stocking Island, Bahamas, for one and two ...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2002
The Shelf and Slope Experimental Taphonomy Initiative was established to measure taphonomic rates... more The Shelf and Slope Experimental Taphonomy Initiative was established to measure taphonomic rates in a range of continental shelf and slope environments of deposition (EODs) over a multiyear period. We deployed experiments on the forereef slope off Lee Stocking Island, Bahamas, and on the continental shelf and slope of the Gulf of Mexico for 2 yr in 18 distinctive EODs at depths from 15 to 530 m. Overall, most shells deployed at most sites had relatively minor changes in shell condition. Most EODs generated relatively similar taphonomic signatures. A few sites did produce taphonomic signatures clearly distinguishable from the central group and these sites were characterized by one or more of the following: high rates of oxidation of reduced compounds, presence in the photic zone, and significant burial and exhumation events. Thus, unique taphonomic signatures are created by unique combinations of environmental conditions that include variables associated with regional gradients, such as depth and light, and variables associated with edaphic processes, such as the seepage of brine or petroleum or the resuspension and redeposition of sediment. Most sites, however, showed similar taphonomic signatures, despite the variety of EOD characteristics present, suggesting that insufficient time had elapsed over 2 yr to generate a more diverse array of taphonomic signatures. Discoloration and dissolution were by far the dominant processes over the 2-yr deployment period. Periostracum breakdown, loss of shell weight, and chipping and breakage was less noticeable. EODs were chosen based on the expectation that the process of burial and the influence of depth and sediment type should play the greatest roles in determining between-EOD differences in taphonomic signature. EOD-specific edaphic factors often overrode the influence of geographic-scale environmental gradients. Taphonomic alteration was greater on
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Bivalve shells deployed experimentally in a variety of environments of deposition (EODs) and over... more Bivalve shells deployed experimentally in a variety of environments of deposition (EODs) and over a wide range of depths from 15 to 570 m in the Bahamas and Gulf of Mexico were assessed for encrusting and endolithic bionts (sclerobionts sensu Taylor and Wilson, 2002) that accumulated over 1-, 2-, 8-and 12/13year intervals. Data include percent coverage and, when possible, identification to generic-or species-level taxonomic categories. Data were binned into two further categories based on guilds and whether or not sclerobionts were judged to be preservable. Each study site shows substantial variability in both percent coverage and species richness/composition, which we attribute to partial burial of different individuals or parts of arrays. Average values of taxonomic richness, guild number, and percent coverage, for a given EOD represent a combination of exposed and buried shells as would be typical of a time-averaged fossil assemblage; maximally covered shells give the potential coverage for each site. In both study areas there are characteristic patterns in terms of overall percentage of shells covered by sclerobionts, numbers and extent of coverage by different guilds as well as by different taxa. For most EODs, there is a progressive, though non-linear increase in both species richness and areal coverage through the twelve years; exceptions are in the 30 m site in the Bahamas, and Parker Bank and Flower Garden sites in the Gulf of Mexico, which show a significant decline in areal coverage (though not in richness). This effect may result from differences in sediment cover over time. These sites showed a tendency to have many or all experimental bags completely sediment covered in the later sampling. Cluster analysis and non-metric multidimensional scaling (NMDS) of various shell substrate species at all EODs from the Bahamas and Gulf of Mexico reveal discrete groupings that are related to both depth (light?) gradient and other factors, such as variations in sedimentation and salinity. Similar numbers of guilds are found at various EODs although the specific guild types represented differ. In general, highest average richness values are recorded for carbonate 70-90 m wall and deep reef sites (69 to 70 taxa) and lowest are for the EFG brine pool (no sclerobionts other than bacterial films after 12/13 years) and deeper dysphotic to subphotic sites (max values: 25 taxa); surprisingly, shallow water sites (b 30 m) yield only moderate diversities of 40-50 taxa. This results in part from the fact that certain encrusters, especially the foraminifer Gypsina and coralline algae tend to overgrow others and dominate space, in addition to burial effects. Certain taxa (notably the serpulid Pseudovermilia) are ubiquitous, while other taxa (e.g. larger foraminifera, vermetid gastropods and many bryozoans) are largely restricted to shallower depths. A combination of species richness, average coverage and key taxa permits discrimination of groups of EODs and potentially, in tandem with other evidence, of depth gradients.
The Paleontological Society Special Publications, 1992
Patterns of epibiont coverage are potentially useful tools in the determination of modern and anc... more Patterns of epibiont coverage are potentially useful tools in the determination of modern and ancient sedimentation rates as well as life habits of host organisms. A study was conducted to characterize patterns of epibiont settlement in various tropical environments and substrate types. Settling plates of clean aragonite shell were placed in six carbonate environments (beach, grass bed, bioturbated sand flat, back reef, forereef, and muddy bay) on St. Croix to document successional trends and timing of infestation by preservable, calcareous epibionts. Coralline algae were first to settle on freshly exposed substrate (within one week), followed by the foraminiferan Planorbulina and serpulid/spirorbid worm tubes. This successional order of epibiont encrustation is proposed as a measure of the length of time a shell has been exposed.The results of this experiment were compared to epibiont patterns on naturally occurring substrates from the same environments. Because the study areas wer...
Geological Society of America Abstracts with Programs
Earth and Life, 2012
The concept of sclerobiofacies is defined herein as suites of sclerobiont encrusters and endiont ... more The concept of sclerobiofacies is defined herein as suites of sclerobiont encrusters and endiont borers (collectively sclerobionts) preserved on skeletons that characterize particular facies/environments. Skeletal components provide biologically standardized substrates; when possible, comparison of encrusting assemblages on fossil shells of the same or closely related eurytopic species provides a degree of substrate control comparable to modern experimentally deployed shells. Taxonomic composition of sclerobiont suites varies rather predictably among marine environments (e.g., based upon depth) but is primarily useful for comparisons of environments within local areas and limited time frames. Parameters that may be used to compare sclerobiofacies across broader spatial and temporal dimensions include: per shell and cumulative species richness (diversity), frequency of encrustation, areal coverage, and guild structure of encrusting taxa. Herein, we summarize characteristic sclerobiofacies in a series of Recent and ancient examples. Modern subtropical marine encrusters, documented on experimentally deployed molluscan shells at sites ranging from 15 to over 200 m, show high biont richness in shallow subtidal areas. Maximal areal coverages in Bahamian samples occur at about 20–30 m, whereas species richness increases downward to the deeper euphotic zone (∼75–80 m). Below this level, rapid decline in both richness and percent coverage results in deeper Dysphotic–Aphotic zone samples yielding only a few species with coverage rarely exceeding 5%. Burial is also a key factor such that rapidly buried shells in the Shallow Euphotic zone have species coverages, richnesses, and taxonomic compositions resembling long-exposed shells in deeper areas below the euphotic zone. Shelly substrates from the Cambrian to Early Ordovician exhibit only minor encrustation by solitary attached taxa, especially echinoderms; however, by the Late Ordovician various solitary (e.g., cornulitids, craniid brachiopods) and colonial forms (e.g., trepostome and tubuliporate bryozoans) form distinctive sclerobiofacies. Photic zone-related environments, judged independently on the basis of microendoliths, show overall lower taxonomic richness than modern counterparts. However, they also show common patterns, including a general decrease of richness and percent encrustation from Shallow Euphotic to Dysphotic/Aphotic zones. Comparable trends are seen in Middle Devonian exemplars from New York State. Not only were there consistent trends toward lowered diversity/coverage into deep-water settings but also an additional factor related to turbidity and/or sedimentation rate was identified from assemblages at comparable depths arrayed along a distal to proximal gradient with respect to siliciclastic input sources. Carboniferous sclerobiont suites from varied sites in North America show many of the same traits as their Devonian counterparts, although detailed depth zonations are not documented at present. The Permo-Triassic extinctions appear to have had a strong impact on the taxonomic composition of marine sclerobiofacies, although a paucity of studies obscures details of Mesozoic and Cenozoic sclerobiofacies. In general, they appear to have taxonomic compositions and patterns similar to those observed in the Recent. The concept of sclerobiofacies provides another tool for paleoenvironmental analysis. Together with litho-, ichno-, bio-, and taphofacies, the properties of shell encrusting assemblages will yield detailed further insights into ancient environmental gradients.
Journal of Shellfish Research, 2008
... The effects of sulfide and an increased food supply on the meiofauna and macrofauna at the Ea... more ... The effects of sulfide and an increased food supply on the meiofauna and macrofauna at the East Flower Garden brine seep. Helgol. Meeresunters 40:5782. CrossRef. Powell, EN, KM Parsons-Hubbard, WR Callender, GM Staff, GT Rowe, CE Brett, SE Walker, A. Raymond, DD ...
PALAIOS, 2002
... Predation on Experimentally Deployed Molluscan Shells from Shelf to Slope Depths in a Tropica... more ... Predation on Experimentally Deployed Molluscan Shells from Shelf to Slope Depths in a Tropical Carbonate Environment. SALLY E. WALKER 1 , KARLA PARSONS-HUBBARD 2 , ERIC POWELL 3 and CARLTON E. BRETT 4 ...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
We utilize information from a suite of molluscan species deployed in a variety of Caribbean and G... more We utilize information from a suite of molluscan species deployed in a variety of Caribbean and Gulf of Mexico environments of preservation (EOP) by SSETI (Shelf and Slope Experimental Taphonomy Initiative) to examine to what degree interpretation of the ...
Earth and Planetary Science Letters, 2006
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
In this paper, we will discuss a two-week experiential learning trip to Indonesia, ranging from t... more In this paper, we will discuss a two-week experiential learning trip to Indonesia, ranging from the design phase to a module course and in-country implementation with two institutional partners in country. The trip involved four faculty and eight students from disciplines ranging from Geology, Anthropology, Environmental Studies to Chemistry and Music. Comparison was at the heart of the project. Our team explored the cultural and functional responses to the 2004 tsunami in Banda Aceh and volcanic eruptions of Mount Merapi in Central Java. Contrasting views of cause and recovery proved especially enlightening. Acehnese responses were tightly woven with immediate pre-tsunami political upheaval along with Islamic framings of the disaster. In comparison, we found responses to volcanic eruptions on Java were quite different because the community affected was more multicultural. We will pepper our account of this pedagogical experience with personal outcomes, cultural interactions, and th...
Palaeogeography, Palaeoclimatology, Palaeoecology, 2011
Palaios, 2008
Examination of remains of Callinectes sapidus deployed in several depth and environmental setting... more Examination of remains of Callinectes sapidus deployed in several depth and environmental settings in the Bahamas and Gulf of Mexico as part of the Shelf and Slope Experimental Taphonomy Initiative project revealed that all specimens were uniformly and strongly de- graded except those in brine-seep settings. Fragmentation and loss of cuticular material at all sites was correlated to the degree
Geology, 1992
... Some studies suggest that storm-induced skeletal transport can be substantial (eg, Westrop, 1... more ... Some studies suggest that storm-induced skeletal transport can be substantial (eg, Westrop, 1986). ... the south seagrass bed, whereas samples from the north seagrass bed were grouped in cluster 4. There were two out-liers: sample 1020, from the back reef, and sam-ple 630 ...
... 1 Department of Geology, Oberlin College, Oberlin, OH 44074, Karla.hubbard{at}oberlin.edu. ..... more ... 1 Department of Geology, Oberlin College, Oberlin, OH 44074, Karla.hubbard{at}oberlin.edu. ... Examples include near-shore carbonate or mixed carbonate/ terrigenous facies (Pilkey et al., 1979; Parsons, 1989; Dent, 1996; Best and Kidwell, 2000a,b; Kidwell et al., 2001), tidal-flat ...