Trapped solar and cosmogenic noble gas abundances in Apollo 15 and 16 deep drill samples

Bogard, D. D.; Nyquist, L. E.; Hirsch, W. C.; Moore, D.R.

doi:10.1016/0012-821x(73)90225-2

Cited by 32 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have considered the change as a function of depths of the ratio of 126 Xe.P/ (1974), since they selected their samples to correspond with those which were used by Russ et al (1972) for the neutron fluence measurements. Rare gas measurements in the surface soil (15041) is from Bogard et al (1973) in the absence of data on this sample from Pepin et al (1974).…”

Section: 'Average' Depths Of Irradiationmentioning

confidence: 99%

Apollo 17 neutron stratigraphy ?Sedimentation and mixing in the lunar regolith

Curtis

Wasserburg

1975

The Moon

View full text Add to dashboard Cite

Abstract. We have measured shifts in the isotopic abunctances of Gd and Sm in soils from the Apollo 17 deep drill stem and calculated the neutron fluence from these measurements. The measurements show two well defined regions of nearly constant fluence: (1) a thick deep section with a very large neutron fluence, and (2) a thinner shallow region with a small fluence. This depth dependence is most plausibly described by a model of rapid accumulation in the last 100-200 m.y., the layered structure reflecting accumulations of isotopically homogeneous source material. This interpretation is compatible with a variety of other characteristics of the soils, including the spallation produced 126 Xe normalized to target element abundances.An alternative model of deposition, followed by irradiation without mixing, followed by shallow mixing will quantitatively describe the data. The model yields an age of 1.25 AE for the bottom of the drill stem. This model was rejected because of the implausible requirement that the soils from the drill stem be accumulated from a source of unirradiated material.The uniformity of various properties of soils provides criteria for defining major stratigraphic intervals in the drill stem which differ from those identified by the Preliminary Examination Team.Neutron fluences measured on shallow and deep soils from all lunar landing sites have been normalized to irradiation in an arbitrary standard chemical environment. We infer from histograms of the normalized fluences that there is a distinct difference in neutron fluence between shallow and deep samples which implies a general vertical stratification of neutron fluence in the lunar regolith.The regolith can be divided into three vertical regions: (1) a well mixed surface layer, ~ 100 g cm-2 thick, with an average fluence of 2.3 x 10 16 n cm-2 , (2) a poorly mixed zone extending from I 00 g cm-2 to at least 500 g cm-2 with an average fluence of 3.5 x 10 16 n cm-2 , and (3) a deep layer of lightly irradiated materials ( < 10 16 n cm-2 ). Analysis of this stratification, using a vertical mixing model, indicates that the probability of mixing to several hundred g cm-2 is comparable to the probability of mixing to several kg cm-2 • This is in contrast to the depth-cratering rate models which have been inferred from crater size frequency distributions using a power law. Alternatively, this discrepancy can be resolved if the true 157 Gd capture rate is t of the value calculated by Lingenfelter et al. (I 972).The most plausible interpretation is that vertical mixing models are not an adequate description of relatively rare deep cratering events which result in significant lateral heterogeneity and addition of unirradiated material to the lunar surface.

show abstract

Section: 'Average' Depths Of Irradiationmentioning

confidence: 99%

Apollo 17 neutron stratigraphy ?Sedimentation and mixing in the lunar regolith

Curtis

Wasserburg

1975

The Moon

View full text Add to dashboard Cite

show abstract

“…In surveying published solar-type Xe data for lunar fines, we find evidence of mass fractionation in many cases (e.g., Bogard et al 1974). Wieler and Baur (1994) identified an isotopically heavier Xe (SEP) component in lunar samples, Table 3 and discussion in text), which represents the zero line.…”

Section: Mass-fractionated Xe Component: Pesyanoe-fmentioning

confidence: 99%

“…3 to 6 include the following published soil data: bulk and grain size separates of 10084, Apollo 12 fines, grain size separates of Apollo 15 fines, and Luna 16 fines; bulk, grain size, and ilmenite separates of 12001, bulk and grain size separates of Apollo 14, 15, and 17, bulk 67701, ilmenite separate of 71501, metal separate of 68501, bulk Apollo 17 deep drill core, and bulk 74261. The following lunar regolith breccia data are also included: 10046, 14301, 14318, 14313, 60019, 60275, 67455, 60255, and bulk and ilmenite separates of 79035 (Podosek et al 1971;Drozd et al 1972;Bogard and Nyquist 1972;Basford et al 1973;Behrmann et al 1973;Bogard et al 1974;Reynolds et al 1974;Bernatowicz et al 1978;Swindle et al 1985;Frick et al 1988;Pepin 1989, 1994;Wieler and Baur 1994;Eugster et al 2001). All Xe literature data are renormalized and corrected for spallation Xe components following the same procedure adopted for Pesyanoe.…”

Section: Evolved Xe Componentsmentioning

confidence: 99%

Solar wind and other gases in the regoliths of the Pesyanoe parent object and the moon

Mathew

Marti

2003

Meteorit & Planetary Scien

View full text Add to dashboard Cite

We report new data from Pesyanoe-90,1 (dark lithology) on the isotopic signature of solar wind (SW) Xe as recorded in this enstatite achondrite which represents a soil-breccia of an asteroidal regolith. The low temperature (≤800°C) steps define the Pesyanoe-S xenon component, which is isotopically consistent with SW Xe reported for the lunar regolith. This implies that the SW Xe isotopic signature was the same at two distinct solar system locations and, importantly, also at different times of solar irradiation. Further, we compare the calculated average solar wind "SW-Xe" signature to Chass-S Xe, the indigenous Xe observed in SNC (Mars) meteorites. Again, a close agreement between these compositions is observed, which implies that a mass-dependent differential fractionation of Xe between SW-Xe and Chass-S Xe is <1.5‰ per amu. We also observe fractionated (Pesyanoe-F) Xe and Ar components in higher temperature steps and we document a fission component due to extinct 244 Pu. Interestingly, the Pesyanoe-F Xe component is revealed only at the highest temperatures (>1200°C). The Pesyanoe-F gas reveals Xe isotopic signatures that are consistent with lunar solar energetic particles (SEP) data and may indicate a distinct solar energetic particle radiation as was inferred for the moon. However, we cannot rule out fractionation processes due to parent body processes. We note that ratios 36 Ar/ 38 Ar ≤5 are also consistent with SEP data. Calculated abundances of the fission component correlate well with radiogenic 40 Ar concentrations, revealing rather constant 244 Pu/K ratios in Pesyanoe, and separates thereof, and indicate that both components were retained. We identify a nitrogen component (δ 15 N = 44‰) of non-solar origin with an isotopic signature distinct from indigenous N (δ 15 N = −33‰). While large excesses at 128 Xe and 129 Xe are observed in the lunar regolith samples, these excesses in Pesyanoe are small. On the other hand, significant 126 Xe isotopic excesses, comparable to relative excesses observed in lunar soils and breccias, are prominent in the intermediate temperature steps of Pesyanoe-90,1.

show abstract

“…b Using particle masses estimated by Kehm et al (2002). Pepin et al (1975) 2.22 ± 0.06 20 µm bulk lunar soil (12001), Eberhardt et al (1972) 2.8 ± 0.5 20-30 µm bulk lunar soil (14163), Bogard and Nyquist (1972) 6.0 ± 0.6…”

Section: Upper Limit Xe Contents In the Idpsmentioning

confidence: 99%

Upper limit concentrations of trapped xenon in individual interplanetary dust particles from the stratosphere

Kehm

Crowther

Gilmour

et al. 2009

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Abstract-The Xe contents in 25 individual stratospheric interplanetary dust particles were measured in two different laboratories using focused laser micro-gas extraction and (1) a conventional low-blank magnetic sector mass spectrometer (Washington University), and (2) a resonance ionization time of flight mass spectrometer (RELAX-University of Manchester). Data from both laboratories yielded a remarkably similar upper-limit 132 Xe concentration in the IDPs (<2.7, 6.8 and 2.2 × 10 −8 ccSTP/g for Washington University Run 1, Washington University Run 2 and University of Manchester analyses, respectively), which is up to a factor of five smaller than previous estimates. The upper-limit 132 Xe/ 36 Ar ratio in the IDPs ( 132 Xe/ 36 Ar < ~8 × 10 −4 for Run 1 and 132 Xe/ 36 Ar < ~19 × 10 −4 for Run 2), computed using 36 Ar concentration data reported elsewhere is consistent with a mixture between implanted solar wind, primordial, and atmospheric noble gases. Most significantly, there is no evidence that IDPs are particularly enriched in primordial noble gases compared to chondritic meteorites, as implied by previous work.

show abstract

Trapped solar and cosmogenic noble gas abundances in Apollo 15 and 16 deep drill samples

Cited by 32 publications

References 13 publications

Apollo 17 neutron stratigraphy ?Sedimentation and mixing in the lunar regolith

Apollo 17 neutron stratigraphy ?Sedimentation and mixing in the lunar regolith

Solar wind and other gases in the regoliths of the Pesyanoe parent object and the moon

Upper limit concentrations of trapped xenon in individual interplanetary dust particles from the stratosphere

Contact Info

Product

Resources

About