Limnocythere gr. inopinata (typically c. 20 valves per sample)
; archiveType changed - was originally Lake sediment (LS)
In a closed, low-latitude lake basin, the d18O values of the lake water, which are the main control on the d18O values of carbonates, are influenced largely by the balance between inflow (mainly shallow groundwater, in the case of Kajemarum) and evaporation (Talbot 1990). Thus, the d18O record in endogenic carbonate should largely reflect salinity.
Changes in d18O values that do not parallel those in Sr/Ca, however, are best explained by changes in water temperature, or in the 18O/16O ratio of precipitation. Changes in the isotopic composition of precipitation may be brought about by shifts in water-vapour source, air temperature (Andrews 1993) or cloud height. Variations in the intensity of monsoon convection may be important, since highly 18O-depleted rainfall is produced by the strong uplift that occurs in monsoon clouds with cold tops (Fontes et al. 1993).
fraction of modern 14C activity uncertainty
210Pb, 239+240Pu or 137Cs activity uncertainty
Y if supported 210Pb activity, N if unsupported 210Pb activity
model used to convert 210Pb activity to age (e.g., constant rate of supply)
years before 1950 (calibrated age, or ages that dont need calibration)
age (MAT5a83d3ba3b): interpretation4_scope: '' has been replaced by 'climate'
age (MAT5a83d3ba3b): interpretation5_scope: '' has been replaced by 'climate'
age (MAT5a83d3ba3b): interpretation6_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation4_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation5_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation6_scope: '' has been replaced by 'climate'
Updated lipdverse database entry with a changed file.
age (MAT5a83d3ba3b): paleoData_units: 'yr AD' has been replaced by 'yr BP'
age (MAT5a83d3ba3b): paleoData_variableName: 'year' has been replaced by 'age'
d18O (LS97HOKA1a): paleoData_isPrimary: '' has been replaced by 'FALSE'
d18O (LS97HOKA1a): paleoData_primaryAgeColumn: '' has been replaced by 'FALSE'
year (MAT5a83d3ba3b): paleoData_isPrimary: '' has been replaced by 'TRUE'
year (MAT5a83d3ba3b): paleoData_primaryAgeColumn: '' has been replaced by 'TRUE'
depth (MATeb6bfe7013): paleoData_isPrimary: '' has been replaced by 'FALSE'
depth (MATeb6bfe7013): paleoData_primaryAgeColumn: '' has been replaced by 'FALSE'
d18O (LS97HOKA1a): interpretation1_basis: 'In a closed, low-latitude lake basin, the d18O values of the lake water, which are the main control on the d18O values of carbonates, are influenced largely by the balance between inflow (mainly shallow groundwater, in the case of Kajemarum) and evaporation (Talbot 1990). Thus, the d18O record in endogenic carbonate should largely reflect salinity.' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_direction: 'negative' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_inferredMaterial: 'lake water' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_rank: '1' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_scope: 'isotope' has been replaced by 'climate'
d18O (LS97HOKA1a): interpretation1_variable: 'hydrologicBalance' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_variableGroup: 'EffectiveMoisture' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_variableGroupDirection: 'negative' has been replaced by ''
d18O (LS97HOKA1a): interpretation1_variableGroupOriginal: 'I_E' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_direction: 'negative' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_inferredMaterial: 'Lake water' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_rank: '2' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_scope: 'isotope' has been replaced by 'climate'
d18O (LS97HOKA1a): interpretation2_variable: 'temperature' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_variableGroup: 'Temperature' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_variableGroupDirection: 'negative' has been replaced by ''
d18O (LS97HOKA1a): interpretation2_variableGroupOriginal: 'T_water' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_basis: 'Changes in d18O values that do not parallel those in Sr/Ca, however, are best explained by changes in water temperature, or in the 18O/16O ratio of precipitation. Changes in the isotopic composition of precipitation may be brought about by shifts in water-vapour source, air temperature (Andrews 1993) or cloud height. Variations in the intensity of monsoon convection may be important, since highly 18O-depleted rainfall is produced by the strong uplift that occurs in monsoon clouds with cold tops (Fontes et al. 1993).' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_inferredMaterial: 'Lake water' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_rank: '3' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_scope: 'isotope' has been replaced by 'climate'
d18O (LS97HOKA1a): interpretation3_variable: 'precipitationIsotope' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_variableGroup: 'P_isotope' has been replaced by ''
d18O (LS97HOKA1a): interpretation3_variableGroupDirection: 'positive' has been replaced by ''
d18O (LS97HOKA1a): interpretation4_basis: '' has been replaced by 'In a closed, low-latitude lake basin, the d18O values of the lake water, which are the main control on the d18O values of carbonates, are influenced largely by the balance between inflow (mainly shallow groundwater, in the case of Kajemarum) and evaporation (Talbot 1990). Thus, the d18O record in endogenic carbonate should largely reflect salinity.'
d18O (LS97HOKA1a): interpretation4_direction: '' has been replaced by 'negative'
d18O (LS97HOKA1a): interpretation4_inferredMaterial: '' has been replaced by 'lake water'
d18O (LS97HOKA1a): interpretation4_rank: '' has been replaced by '1'
d18O (LS97HOKA1a): interpretation4_scope: '' has been replaced by 'isotope'
d18O (LS97HOKA1a): interpretation4_variable: '' has been replaced by 'hydrologicBalance'
d18O (LS97HOKA1a): interpretation4_variableGroup: '' has been replaced by 'EffectiveMoisture'
d18O (LS97HOKA1a): interpretation4_variableGroupDirection: '' has been replaced by 'negative'
d18O (LS97HOKA1a): interpretation4_variableGroupOriginal: '' has been replaced by 'I_E'
d18O (LS97HOKA1a): interpretation5_direction: '' has been replaced by 'negative'
d18O (LS97HOKA1a): interpretation5_inferredMaterial: '' has been replaced by 'Lake water'
d18O (LS97HOKA1a): interpretation5_rank: '' has been replaced by '2'
d18O (LS97HOKA1a): interpretation5_scope: '' has been replaced by 'isotope'
d18O (LS97HOKA1a): interpretation5_variable: '' has been replaced by 'temperature'
d18O (LS97HOKA1a): interpretation5_variableGroup: '' has been replaced by 'Temperature'
d18O (LS97HOKA1a): interpretation5_variableGroupDirection: '' has been replaced by 'negative'
d18O (LS97HOKA1a): interpretation5_variableGroupOriginal: '' has been replaced by 'T_water'
d18O (LS97HOKA1a): interpretation6_basis: '' has been replaced by 'Changes in d18O values that do not parallel those in Sr/Ca, however, are best explained by changes in water temperature, or in the 18O/16O ratio of precipitation. Changes in the isotopic composition of precipitation may be brought about by shifts in water-vapour source, air temperature (Andrews 1993) or cloud height. Variations in the intensity of monsoon convection may be important, since highly 18O-depleted rainfall is produced by the strong uplift that occurs in monsoon clouds with cold tops (Fontes et al. 1993).'
d18O (LS97HOKA1a): interpretation6_inferredMaterial: '' has been replaced by 'Lake water'
d18O (LS97HOKA1a): interpretation6_rank: '' has been replaced by '3'
d18O (LS97HOKA1a): interpretation6_scope: '' has been replaced by 'isotope'
d18O (LS97HOKA1a): interpretation6_variable: '' has been replaced by 'precipitationIsotope'
d18O (LS97HOKA1a): interpretation6_variableGroup: '' has been replaced by 'P_isotope'
d18O (LS97HOKA1a): interpretation6_variableGroupDirection: '' has been replaced by 'positive'
year (MAT5a83d3ba3b): interpretation1_scope: '' has been replaced by 'climate'
year (MAT5a83d3ba3b): interpretation2_scope: '' has been replaced by 'climate'
year (MAT5a83d3ba3b): interpretation3_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation1_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation2_scope: '' has been replaced by 'climate'
depth (MATeb6bfe7013): interpretation3_scope: '' has been replaced by 'climate'
d18O (LS97HOKA1a): interpretation1_variable: 'I_E' has been replaced by 'hydrologicBalance'
d18O (LS97HOKA1a): interpretation2_variable: 'T_water' has been replaced by 'temperature'
d18O (LS97HOKA1a): interpretation3_variable: 'P_isotope' has been replaced by 'precipitationIsotope'
Changes made as part of LiPDverse vocabulary standardization process
d18O (LS97HOKA1a): paleoData_longName: '' has been replaced by 'AD'
year (MAT5a83d3ba3b): paleoData_units: 'AD' has been replaced by 'yr AD'
year (MAT5a83d3ba3b): paleoData_longName: '' has been replaced by 'AD'
depth (MATeb6bfe7013): paleoData_longName: '' has been replaced by 'AD'
Holmes, J. A. , Street-Perrott, F. A. , Allen, M. J. , Fothergill, P. A. , Harkness, D. D. , Kroon, D. , Perrott, R. A.
HOLMES, J. A., STREET-PERROTT, F. A., ALLEN, M. J., FOTHERGILL, P. A., HARKNESS, D. D., KROON, D. and PERROTT, R. A.: Holocene palaeolimnology of Kajemamm Oasis, Northern Nigeria: an isotopic study of ostracodes, bulk carbonate and organic carbon, Journal of the Geological Society, 154(2), 311–319, doi:10.1144/gsjgs.154.2.0311, 1997.
Holocene palaeolimnology of Kajemamm Oasis, Northern Nigeria: an isotopic study of ostracodes, bulk carbonate and organic carbon