This page contains details regarding the compilation of hysteresis data from carbonate rocks (both with primary and secondary magnetizations) that was published in the Jackson and Swanson-Hysell, 2012 paper entitled “Rock Magnetism of Remagnetized Carbonate Rocks: Another Look.”

This compilation was also published in Swanson-Hysell et al., 2012 where it included additional data from Bitter Spring Formation limestones and dolostones. In addition, since publication in Jackson and Swanson-Hysell, 2012 we have added data from the Organyà Basin from Dinares-Turell and Garcia-Senz (2000) that were graciously provided by Jaume Dinarès-Turell. These data are included in the plots at the bottom of the page.

A few details and a .csv file are provided below for each study included in the compilation. These data were taken both from either data tables within the respective papers or, more commonly, from the digitization of papers when the data were not reported in tables. The B_cr/B_c and M_r/M_s ratios could be obtained from all studies in this compilation, but it was rare that the data were sufficiently presented to be able to make seperate squareness-coercivity plots. When the data were reported to this level it is also compiled. The MATLAB code snippets embedded in the page simply load and plot the compiled summary hysteresis parameters.

There are surely more data sets that can be added to this current compilation. If you know of existing datasets to add to this compilation it would be great if you would be willing forward them along to me (swanson-hysell@berkeley.edu).

Background on the “fingerprint” of remagnetization based on hysteresis parameters

Hysteresis experiments, as well as other experiments such as the frequency dependence of susceptibility, have led to the recognition that the dominant magnetic carriers in many remagnetized carbonate units are very fine-grains in the superparamagnetic (SP) and stable single-domain (SSD) size range. The high proportions of these SP and SSD particles results in hysteresis summary parameters (coercivity B_c; remanent coercivity B_cr; saturation magnetization M_s; saturation remanence M_r) whose combination on a “Day Plot” of B_cr/B_c vs M_r/M_s leads to points in a region that is distinct from most other rocks (see diamonds in figure below). This hysteresis behavior led to the suggestion that these parameters could be used as a fingerprint for recognition of remagnetization in carbonate rocks (Jackson, 1990; Channel & McCabe 1994). The basis and limitations of this idea are explored in depth in Jackson and Swanson-Hysell, 2012.

At this time, we are unaware of any such ‘false positives’ in the published literature where carbonates with demonstrably primary magnetization yield hysteresis parameters in the range typically restricted to remagnetized carbonates. Instead, as can seen in the plot below, hysteresis parameters from carbonates with demonstrably primary magnetizations held by magnetite yield parameters along the stable single-domain to multidomain mixing line—as is common for geological materials. As we explored in Jackson and Swanson-Hysell, 2012 the lack of ‘false positives’ is in some ways surprising given the possibility that such parameters could arise from either: (1) a primary population of grains in a carbonate rock isolated from detrital input or (2) in a situation where primary magnetite persists while a secondary mineral of contrasting coercivity forms. Regarding the first point, further data are needed to evaluate whether a similar SP-SSD particle-size distribution could arise in the primary magnetic mineralogy of shallow-water carbonates that are isolated from detrital input. There is a paucity of data from units such as modern shallow-water carbonate muds. Regarding the second point, and as we write in Jackson and Swanson-Hysell, 2012: Given the common occurrence of goethite as a surface weathering product and the precipitation of secondary iron sulphides through fluid flow or early diagenesis, interpretations of hysteresis loop parameters should be made cautiously and be paired with other rock magnetic experiments that can demonstrate a largely mono-mineralic population of ferrimagnetic grains.

Modified from figure 1 of Jackson and Swanson-Hysell, 2012 (needs to be updated to include Dinarès-Turell2000 and Swanson-Hysell2012 data. (A) Summary Day plot of published hysteresis parameters for carbonate rocks, in which the ratio of remanent coercivity Bcr to coercivity Bc is plotted against the ratio of saturation remanence Mr to saturation magnetization (Ms). Data from carbonates interpreted to carry primary remanence are marked with circles, and data from carbonates interpreted to be remagnetized are marked with diamonds. (B) An example hysteresis loop from sample H2-5.35 of the Manlius Formation of the Helderberg Group is shown with Bc, Mr and Ms marked. Note that the loop had not reached saturation by 100 mT (the maximum of the x-axis), such that Ms is not reached until higher applied fields (off the plot).

Data Compilation Contents

Data sets from carbonate formations with interpreted primary magnetization

Tarduno1994b Laytonville Limestone (primary magnetization)

These data are from the Laytonville Limestone–a Cretaceous pelagic Limestone from northern California in an accreted terrain. Some samples contain hematite (Red Laytonville Limestone) and are not included in the compilation. White limestones with neglible hematite are compared in the paper to reference pelagic limestone data and are indistinguishable. A primary magnetization for the Laytonville Limestone is supported by the fact that the trend in inclination matches the expected sense of motion predicated by the North American APW path. Download .csv file of data for the White Laytonville Limestone

[Tarduno1994b_Bcr_Bc Tarduno1994b_Mr_Ms]=textread('Tarduno1994b_white.csv','','delimiter',',','headerlines',3);

Channell1994a Maiolica Limestone (primary magnetization)

These data are from the latest Jurassic to early Cretaceous pelagic Maiolica Limestone. A primary origin of the magnetization has been demonstrated through the consistent correlation of polarity zones to biostratigraphically correlatable sections. Download .csv file of data

[Channell1994a_Bcr_Bc Channell1994a_Mr_Ms]=textread('Channell1994a.csv','','delimiter',',','headerlines',3);

Abrajevitch2009a ODP 738 Indian Ocean chalks

These data are from base Paleocene calcareous chalks from southern Indian Ocean ODP site 738 where the high B_cr/B_c points are from laminated (right after the K/P boundary) seds while the low B_cr/B_c points are from a bioturbated interval above. The interpretation in the study is that the laminated sediments are dominated by a detrital flux while the bioturbated interval includes biochemically precipitated magnetite. Download .csv file of data

[Abrajevitch2009a_Bcr_Bc Abrajevitch2009a_Mr_Ms]=textread('Abrajevitch2009a.csv','','delimiter',',','headerlines',3);

Belkaaloul1997a Paris Basin carbonates

These data are from middle to upper Jurassic carbonates of the Paris Basin. These are shallow water carbonates: ooilitic grainstones, oolitic-skeletal limestones. Work on Lower Jurassic carbonates has revealed a robust magnetostrat record (Yang1996a), but I haven’t found whether more work has been done on these middle to upper Jurassic carbonates. This study was meant as a rock magnetic survey to establish whether the carbonates were remagnetized or not so that further magnetostratigraphy could be done. Download .csv file of data

[Belkaaloul1997a_Bcr_Bc Belkaaloul1997a_Mr_Ms]=textread('Belkaaloul1997a.csv','','delimiter',',','headerlines',3);

Menabreaz2010a Pleistocene Tahiti Reef

These data are from a late Pleistocene Reef offshore of Tahiti and are from samples that include the reef framework and skeletal limestone. There are some volcaniclastic sands that are interbedded in the stratigraphy and are likely contributing detrital titanomagnetite to the reef. Download .csv file of data

[Menabreaz2010a_Bcr_Bc Menabreaz2010a_Mr_Ms]=textread('Menabreaz2010a.csv','','delimiter',',','headerlines',3);

Dinares-Turell & Garcia-Senz 2000 Aptian-Albian and Upper Cretaceous strata of the Organyà Basin

These data from the Aptian-Albian and Upper Cretaceous strata of the Organyà Basin are interpreted to have a primary magnetization on the basis of polarity (normal corresponding to C34n—Cretaceous long normal), of a positive fold test and of the coincidence of the mean directions with expected reference directions for Iberia. Download .csv file of data

[DT2000primary_Bc DT2000primary_Bcr DT2000primary_Bcr_Bc  DT2000primary_Mr DT2000primary_Ms DT2000primary_Mr_Ms]=textread('Dinares-Turell2000primary_hyst.csv','','delimiter',',','headerlines',2);
DT2000primary_Bc=DT2000primary_Bc/10; %converting from Oe to mT

Data sets from carbonate formations interpreted to be remagnetized

Jackson1990a Onondaga Limestone, Trenton Limestone, Knox Dolomite

These North American carbonate formations are interpreted to have been remagnetized during the Kiaman reversed polarity superchron. Download .csv file of data

[Jackson1990a_Bc Jackson1990a_Bcr Jackson1990a_Bcr_Bc Jackson1990a_Mr_Ms] = textread('Jackson1990a.csv','','delimiter',',','headerlines',1);
Jackson1990a_Bc=Jackson1990a_Bc/10; %converting from Oe to mT

McCabe1994a_Craven Craven Basin Limestones

These data are from samples of Lower Carboniferous Chatburn and Pendleside Limestones from the Craven Basin (northern England) intrepreted to carry a syn-Hercynian remagnetization held by magnetite. Download .csv file of data

[McCabe1994a_Craven_Bcr_Bc McCabe1994a_Craven_Mr_Ms]=textread('McCabe1994a_Craven.csv','','delimiter',',','headerlines',3);

McCabe1994a_Onondaga Onondaga Limestone

McCabe, C., and Channell, J. E. T., 1994, Late Paleozoic remagnetization in limestones of the Craven Basin (northern England) and the rock magnetic fingerprint of remagnetized sedimentary carbonates: Journal of Geophysical Research, v. 99, n. B3, p. 4603– 4612, http://dx.doi.org/10.1029/93JB02802

These data are from the Onondaga Limestone of NY State that is interpreted to be remagnetized. Download .csv file of data

[McCabe1994a_Onondaga_Bcr_Bc McCabe1994a_Onondaga_Mr_Ms]=textread('McCabe1994a_Onondaga.csv','','delimiter',',','headerlines',3);

McCabe1994a_GreatBasin_Alaska

McCabe, C., and Channell, J. E. T., 1994, Late Paleozoic remagnetization in limestones of the Craven Basin (northern England) and the rock magnetic fingerprint of remagnetized sedimentary carbonates: Journal of Geophysical Research, v. 99, n. B3, p. 4603– 4612, http://dx.doi.org/10.1029/93JB02802

These data are from Ordovician Poganip Group carbonates from the Great Basin (Nevada) and from the Mississippian Peratrovich Formation (Alexander Terrane, SE Alaska). Both units are interpreted to be remagnetized with a magnetization carried by magnetite. The data between the two units are not differentiated from one another in the figure from which the data were obtained. Download .csv file of data

[McCabe1994a_GreatBasin_Alaska_Bcr_Bc McCabe1994a_GreatBasin_Alaska_Mr_Ms]=textread('McCabe1994a_Onondaga.csv','','delimiter',',','headerlines',3);

Elmore2006a Helderberg Group and the Tonoloway Formation

These data are from the Helderberg Group and the Tonoloway Formation in the Valley and Ridge province of West Virginia. The magnetization is a syntilting remanence that corresponds to 30% untilting for the Helderberg and 76% untilting for the Tonoloway. Magnetization was acquired during the late Paleozoic superchron. Download .csv file of data

[Elmore2006a_Bcr_Bc Elmore2006a_Mr_Ms]=textread('Elmore2006a_day_plot.csv','','delimiter',',','headerlines',3);

Xu1998a Lower Carboniferous Leadville Formation

These data are from the Lower Carboniferous Leadville Formation of central Colorado that has undergone multiple remagnetization events that are interpreted to be associated with burial diagenesis and sulfide mineralization. Pyrrhotite is interpreted to be a significant contributor to remanence and to carry a late Cretaceous remagnetization in addition to the remagnetization carried by magnetite. The data of Banjeree1997a from the formation above the Leadville could also be included on the compilation (it is not currently), but the magnetite in the carbonates is not convincingly shown to be a remagnetization. Download .csv file of B_cr/B_c and M_r/M_s data; Download .csv file of B_c and M_r/M_s data

[Xu1998a_Bcr_Bc Xu1998a_Mr_Ms]=textread('Xu1998a_day_plot.csv','','delimiter',',','headerlines',3);
[Xu1998a_Bc Xu1998a_Mr_Ms_B]=textread('Xu1998a_squareness_coercivity_plot.csv','','delimiter',',','headerlines',3);

Dinares-Turell & Garcia-Senz 2000 Berriasian-Hauterivian and older Baremian strata of the Organyà Basin

These data from Berriasian-Hauterivian and older Baremian carbonates of the Organyà Basin are interpreted to have been remagnetized. The strata are of a single polarity despite the fact that biostratigraphy places age constraints during a time when there should have been numerous reversals. Download .csv file of data

[DT2000remag_Bc DT2000remag_Bcr DT2000remag_Bcr_Bc  DT2000remag_Mr DT2000remag_Ms DT2000remag_Mr_Ms]=textread('Dinares-Turell2000remag_hyst.csv','','delimiter',',','headerlines',2);
DT2000remag_Bc=DT2000remag_Bc/10; %converting from Oe to mT

Swanson-Hysell2012a Bitter Springs Formation, central Australia

Swanson-Hysell, N.L., Maloof, A.C., Kirschvink, J.L., Halverson, G.P., and Hurtgen, M.T.  Constraints on Neoproterozoic paleogeography and Paleozoic orogenesis from paleomagnetic records of the Bitter Springs Formation, Amadeus Basin, central Australia. American Journal of Science, (2012), 312, 817-884, http://dx.doi.org/10.2475/08.2012.01

These data are from limestone and dolostone samples of the Love’s Creek Member of the Neoproterozoic Bitter Springs Formation of the Amadeus Basin of central Australia. The paleomagnetic pole from the the Love’s Creek Member corresponds with the Cambrian apparent polar wander path for Australia rendering it likely that the remanence is a remagnetization that occurred during burial diagenesis associated with Cambrian sedimentation in the basin. At this time, the carbonates would have passed through temperatures that could have led to smectite to illite conversion and associated magnetite authigenesis. A primary origin for the magnetite remanence can’t fully be ruled out and is explored in the paper, but it is most likely that the magnetite is secondary and represent a remagnetization.

Hysteresis data were obtained both from samples obtained from outcrop and samples taken from deep (>1 km) stratigraphic drill core. The loops from both outcrop and core are distinctly wasp-waisted. Outcrop samples contain goethite (confirmed through low temperature remanence cycling experiments) which could be contributing to the constriction in the loops. In core samples, low temperature remanence experiments reveal the presence of pyrrhotite whose remanence is also observed in outcrop samples that underwent progressive thermal demagnetization. The contrasting coercivities of the multiple mineralogies could be a major factor leading to the wasp-waisting. However, there is a large decrease in remanence from 10 to 30 K during remanence upon warming experiments (fig. 13 of Swanson-Hysell et al., 2012) that indicates the presence of a significant population of superparamagnetic grains. This result suggests that SP magnetite is playing a role in the constriction of the loops. Download hysteresis summary parameters for subsurface drill core samples; Download hysteresis summary parameters for outcrop samples

[S_H2012a_core_Mr S_H2012a_core_Ms S_H2012a_core_Bc S_H2012a_core_Bcr S_H2012a_core_Bcr_Bc S_H2012a_core_Mr_Ms]=textread('S_H2012a_core_Hysteresis.csv','','delimiter',',','headerlines',1);
[S_H2012a_outcrop_Mr S_H2012a_outcrop_Ms S_H2012a_outcrop_Bc S_H2012a_outcrop_Bcr S_H2012a_outcrop_Bcr_Bc S_H2012a_outcrop_Mr_Ms]=textread('S_H2012a_outcrop_Hysteresis.csv','','delimiter',',','headerlines',1);

DAY PLOT LINEAR AXES

DayPlotLinear = figure;
%plot non-remag as circles
plot(Tarduno1994b_Bcr_Bc,Tarduno1994b_Mr_Ms,'o','MarkerEdgeColor', [1 .75 0])
hold on
plot(Channell1994a_Bcr_Bc,Channell1994a_Mr_Ms,'o','MarkerEdgeColor', [1 0.5 0])
plot(Abrajevitch2009a_Bcr_Bc,Abrajevitch2009a_Mr_Ms,'o','MarkerEdgeColor', [1 0.25 0])
plot(Belkaaloul1997a_Bcr_Bc,Belkaaloul1997a_Mr_Ms,'o','MarkerEdgeColor', [1 0 0])
plot(Menabreaz2010a_Bcr_Bc,Menabreaz2010a_Mr_Ms,'o','MarkerEdgeColor', [.75 0 0])
plot(DT2000primary_Bcr_Bc,DT2000primary_Mr_Ms,'o','MarkerEdgeColor', [.75 .75 0])
%plot remag as diamonds
plot(Jackson1990a_Bcr_Bc,Jackson1990a_Mr_Ms,'d','MarkerEdgeColor', [0 .7 .9])
plot(McCabe1994a_Craven_Bcr_Bc,McCabe1994a_Craven_Mr_Ms,'d','MarkerEdgeColor', [0 1 .9])
plot(McCabe1994a_Onondaga_Bcr_Bc,McCabe1994a_Onondaga_Mr_Ms,'d','MarkerEdgeColor', [0 1 .7])
plot(McCabe1994a_GreatBasin_Alaska_Bcr_Bc,McCabe1994a_GreatBasin_Alaska_Mr_Ms,'d','MarkerEdgeColor', [0 1 .5])
plot(Elmore2006a_Bcr_Bc,Elmore2006a_Mr_Ms,'d','MarkerEdgeColor', [0 1 .3])
plot(Xu1998a_Bcr_Bc,Xu1998a_Mr_Ms,'d','MarkerEdgeColor', [0 1 .1])
plot(DT2000remag_Bcr_Bc,DT2000remag_Mr_Ms,'d','MarkerEdgeColor', [0 .5 0])
plot(S_H2012a_core_Bcr_Bc,S_H2012a_core_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5],'MarkerFaceColor',[0.5 0.5 0.5])
plot(S_H2012a_outcrop_Bcr_Bc,S_H2012a_outcrop_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5])

legend('Laytonville Limestone (Tarduno1994b)','Maiolica Limestone (Channell1994a)','Paleocene Chalk (Abrajevitch2009a)',...
'Paris Basin Shallow-water limestones (Belkaaloul1997a)','Tahiti Pleistocene Reef (Menabreaz2010a)','Organya Basin primary limestones (Dinares-Turell2000)',...
'NE USA Paleozoic Carbonates (Jackson1990a)','Craven Basin Limestone (McCabe1994a)','Onondaga Limestone Limestone (McCabe1994a)',...
'Great Basin/Alaska remag carbonates (MacCabe1994a)','Ordovician/Devonian WV limestone (Elmore2006a)','Leadville carbonates (Xu1998a)',...
'Organya Basin remag limestones (Dinares-Turell2000)','Bitter Springs Fm core (Swanson-Hysell2012a)',...
'Bitter Springs Fm outcrop (Swanson-Hysell2012a)','location','southoutside')
xlabel('B_c_r / B_c','FontSize',12)
ylabel('M_r / M_s','FontSize',12)
title('Day Plot of summary hysteresis parameters from carbonates with primary and secondary magnetizations')

DAY PLOT LOG AXES

DayPlotLog = figure;
%loglog non-remag as circles
loglog(Tarduno1994b_Bcr_Bc,Tarduno1994b_Mr_Ms,'o','MarkerEdgeColor', [1 .75 0])
hold on
loglog(Channell1994a_Bcr_Bc,Channell1994a_Mr_Ms,'o','MarkerEdgeColor', [1 0.5 0])
loglog(Abrajevitch2009a_Bcr_Bc,Abrajevitch2009a_Mr_Ms,'o','MarkerEdgeColor', [1 0.25 0])
loglog(Belkaaloul1997a_Bcr_Bc,Belkaaloul1997a_Mr_Ms,'o','MarkerEdgeColor', [1 0 0])
loglog(Menabreaz2010a_Bcr_Bc,Menabreaz2010a_Mr_Ms,'o','MarkerEdgeColor', [.75 0 0])
loglog(DT2000primary_Bcr_Bc,DT2000primary_Mr_Ms,'o','MarkerEdgeColor', [.75 .75 0])

%loglog remag as diamonds
loglog(Jackson1990a_Bcr_Bc,Jackson1990a_Mr_Ms,'d','MarkerEdgeColor', [0 .7 .9])
loglog(McCabe1994a_Craven_Bcr_Bc,McCabe1994a_Craven_Mr_Ms,'d','MarkerEdgeColor', [0 1 .9])
loglog(McCabe1994a_Onondaga_Bcr_Bc,McCabe1994a_Onondaga_Mr_Ms,'d','MarkerEdgeColor', [0 1 .7])
loglog(McCabe1994a_GreatBasin_Alaska_Bcr_Bc,McCabe1994a_GreatBasin_Alaska_Mr_Ms,'d','MarkerEdgeColor', [0 1 .5])
loglog(Elmore2006a_Bcr_Bc,Elmore2006a_Mr_Ms,'d','MarkerEdgeColor', [0 1 .3])
loglog(Xu1998a_Bcr_Bc,Xu1998a_Mr_Ms,'d','MarkerEdgeColor', [0 1 .1])
loglog(DT2000remag_Bcr_Bc,DT2000remag_Mr_Ms,'d','MarkerEdgeColor', [0 .5 0])
loglog(S_H2012a_core_Bcr_Bc,S_H2012a_core_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5],'MarkerFaceColor',[0.5 0.5 0.5])
loglog(S_H2012a_outcrop_Bcr_Bc,S_H2012a_outcrop_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5])
axis([1 30 .03 1])

legend('Laytonville Limestone (Tarduno1994b)','Maiolica Limestone (Channell1994a)','Paleocene Chalk (Abrajevitch2009a)',...
'Paris Basin Shallow-water limestones (Belkaaloul1997a)','Tahiti Pleistocene Reef (Menabreaz2010a)','Organya Basin primary limestones (Dinares-Turell2000)',...
'NE USA Paleozoic Carbonates (Jackson1990a)','Craven Basin Limestone (McCabe1994a)','Onondaga Limestone Limestone (McCabe1994a)',...
'Great Basin/Alaska remag carbonates (MacCabe1994a)','Ordovician/Devonian WV limestone (Elmore2006a)','Leadville carbonates (Xu1998a)',...
'Organya Basin remag limestones (Dinares-Turell2000)','Bitter Springs Fm core (Swanson-Hysell2012a)',...
'Bitter Springs Fm outcrop (Swanson-Hysell2012a)','location','southoutside')
xlabel('B_c_r / B_c','FontSize',12)
ylabel('M_r / M_s','FontSize',12)
title('Day Plot of summary hysteresis parameters from carbonates with primary and secondary magnetizations')

SQUARENESS-COERCIVITY PLOT

SC_plot = figure;

%semilogx remag as diamonds
semilogx(Jackson1990a_Bc,Jackson1990a_Mr_Ms,'d','MarkerEdgeColor', [0 .7 .9])
hold on
semilogx(Xu1998a_Bc,Xu1998a_Mr_Ms_B,'d','MarkerEdgeColor', [0 1 .1])
semilogx(DT2000primary_Bc,DT2000primary_Mr_Ms,'o','MarkerEdgeColor', [.75 .75 0])
semilogx(DT2000remag_Bc,DT2000remag_Mr_Ms,'d','MarkerEdgeColor', [0 .5 0])
semilogx(S_H2012a_core_Bc,S_H2012a_core_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5],'MarkerFaceColor',[0.5 0.5 0.5])
semilogx(S_H2012a_outcrop_Bc,S_H2012a_outcrop_Mr_Ms,'d','MarkerEdgeColor',[0.5 0.5 0.5])
axis([2 300 0 0.7])

legend('NE USA Paleozoic Carbonates (Jackson1990a)', 'Leadville carbonates (Xu1998a)','Organya Basin primary limestones (Dinares-Turell2000)',...
    'Organya Basin remag limestones (Dinares-Turell2000)','Bitter Springs Fm core (Swanson-Hysell2012a)',...
    'Bitter Springs Fm outcrop (Swanson-Hysell2012a)','location','southoutside')
xlabel('B_c','FontSize',12)
ylabel('M_r / M_s','FontSize',12)
title('Squareness-coercivity plot of summary hysteresis parameters')

Data to add

Eocene-Oligocene pelagic carbonates from the Southern Ocean

Roberts, A. P., L. Chang, D. Heslop, F. Florindo, and J. C. Larrasoana (2012), Searching for single domain magnetite in the ‘pseudo-single-domain’ sedimentary haystack: Implications of biogenic magnetite preservation for sediment magnetism and relative paleointensity determinations, J. Geophys. Res., doi:10.1029/2012JB009412.