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Trace elements in fines from the Apollo 15 deep drill
706
xotes
SANDELLE. B. (1962) The beryllium content of igneous rocks. Qeochim. Cosmochim. acta 2, 211-216. SHALE D. R. and BERNOLD S. (1964) Distribution of beryllium in igneous rocks. U.S. Beol. Surv., Prof. Paper 501-B, 100-104. SEAWE D. R. and BERNOLD S. (1966) Beryllium content of volcanic rocks. U.S. Geol. Sure. Bull. 1214-C, 11. SIQKCNOLFI G. P. (19’70) Investigations into the deep levels of the continental crust: petrology and chemistry of the granulite facies terrains of Southern Bahia (Brazil). Atti Sot. Tosc. SC. Nat. &fern. A17, 327-341. SIOHMOLPI G. P. (1971) Investigations into deep crustal levels: fractionating effecta and geochemical trends related to high-grade metamorphism. f_Jwchim. Coemochim. Acta 35, 10061021. SIOEINOLIFI G. P. (1972) Determination of beryllium in standard rock samples by flameless A. A. spectroscopy. Atomic Absorption Newektter II, 96-98. SLEPNEYY. S. (1969) The characteristics of distribution of some rare elements in metamorphio rocks, granites, and rare metal pegmatites of the Sayan Mountains. Ueochemietry (USSR) (English Transl.) 4, 312-314. TAYLOR S. R. (1964) Abundance of chemical elements in the continental crust: a new table. Qeochim. Coemochim. Acta aS, 1273-1285. Oeochlmica et Coamochlmica Aeta,1973.Vol. 97, pp. 706to 708. Pergamon Pm.
Trace elements
in finesfrom
the
Apoh
PrIntedin Northern Ireland
15 deep dpill
PHILIP A. HELMKE, KAREN M. TELANDEB, CHARLES K. WEISS and L-Y A. BASEIN Department of Chemistry, University of Wisconsin-Madison, (Received 22 August 1972: accepted in rev&&form
53706, U.S.9.
10 October 1972)
Al&&--No systematic variations in concentrations with depth were found for lOtrace elements in samplea from the Apollo 15 deep drill. Presence of a sign&ant amount of KREEP is indiceted.
SAMPLESof fines ( < 1 mm) from the bottom of the Apollo 16 deep drill core and from each junction between the six 42.5 cm long segments of the drill stem were analyzed for Ag, Co, Cr, Cs, Cu, Ga, Hf, Rb, SC and Zn by neutron activation. Prooedures used were adapted from our earlier work (-KIN et al., 1970 ; ALLEN eb al., 1970). The samples weighed approximately 50 mg each ctnd were splits of approximately 2 g, sieved samples used for biomedical testing. The results of the analyses are shown in Fig. 1. The indicated analytical uncertainties are based mainly on counting statistics. The samples were subjected to a minimum of kndling in our laboratory prior to neutron irradiation. Each plastic vial was removed from its inner T&on@ bag and opened inside a cleaned stainless steel and luoite cabinet in an air atmosphere. The contents were transferred immediately into weighed, cleaned quartz tubes. The tubes were weighed with$he samples in them and sealed off. Exposure time between opening the plastic vials and sealing the quartz tubes ranged from 5 to 16 minutes. The samples were irradiated for 7 hours at a neutron flux of approximately lOls n/cmz/ sec.
707
Notee
The most striking feature of the results (Fig. 1) is the absence of signifknt variations in ooncentration for any element, within the limits of the analytical unoertainties, throughout the 240 cm depth of the drill sample and despite the considerable stratigraphy of the oared material (determined by X-radiography by G. Heiken and J. Lindsay). Variations in concentrations of So and Cu amounting to about 10 per cent and of Cr, Hf and Rb of up to 20 per oent were observed, but these variations are not oorrelated with each other. This suggests that either the regolith where the drill core was taken has been chemically homogenized by local events or that the drill did not penetrate through the last major blanket of material laid down at the site. The composition of the material from the drill differs signifkantly from that of surface fines 15601 and 16471 near Hadley Rille and Dune orater (HELBEKEand HasKIN, 1972). The oonoentrations of SC, Co and Ga in material from the deep drill are substantially lower (factors of 0.67 to 0.87) but those of Zn, Hf and Cr are about the same as in ties 16601 and 16471. The concentrations for all elements exceptGa (a little low) and Ag (high) fall within the ranges reported for fks from thether lunar missions.
3
z
moo2. 207 --I21)
2 14;::; % lmool ,239’ 23’
on3
0.l
!I0 ELEMENT=
rxiAmT,oN
loo
5 rpplry
Fig. 1. Concentrations for 10 trace elements in samplea from the Apollo 16 deep drill core have been plotted again& approximate depths in the drill atem. Sample numbere arc given beaide the depths.
The oonoentration range for Ag is well above that of about 10-30 ppb reported for ties from other Apollo missions (e.g., QmapaTrzv et aE.,1970; Lam, et a2., 1971; MOXUUN et a;Z.,1972). This implies that most of the Ag we observed is a oontaminant. The contamination may have ooourred in our laboratories. However, brazing materials used in the manufacture of the drill bit oontain Ag as a major oonstituent, along with Cu and Zn (L. Silver, private communication). The high values for Ag may thus have resulted from abrasion of the bit by the lunar material during drill@ The quantity of brasing material required to contaminate the sample sign&a&y with Ag is only about one-thousandth that required to contaminate the sample to the same degree with Cu or Zn.
708
Notes
The concentrations of Co and SC in the Gnes from the deep drill are lower (factors of O-7 and O-6) and those of Hf (factor of 1.7) and Rb and Cs (factor of about 10) are higher than the averages found for four ApoIIo 15 igneous rocks (unpubhshed data). This suggests the presence of a significant KREEP component with a composition similar to that of 12013 in the fines. Acknwkdgemmte-We thank the crew of the University of Wisoonsin nuolear reactor for irradiatingthe samples. We are grateful to Astronauts Scold and Ium for their special efforts that made these samples available. This work was supported in part by the National Aeronautics and Space Administration under grant NQL-50-002-148. REFERENCES ALLEN R. O., HasL. A., ANDEESON M. R. and MifLLzm0. (1970) Neutron activation analysis for 39 elements in small or precious geologic samples. J. Radioanal. Chetn. 6, 115-137. GANAPATHIT R., Rm R., hAY9 R., Lawn J. C. and ANDu.uaE. (1970) Trace elements in Apollo 11 lunar rooks: implication for meteorite influx and origin of moon. Proc. ApoZlu 11 Lunar Ski. Cmf., (editor A. A. Levinson), Vol. 2, 1117-I 142. Pergamon. HasL. A., ALLEN R. O., HELMEE P. A., PAETER T. P., ANDEESON M. A., KOWTEV R. L. and Zm K. A. (1970) Rare earths and other trace elements in Apollo 11 lunar samples. Proc. Apollo 11 Lunar Sci. Conf., (editor A. A. Levinson), Vol. 2, 1213-1231. Pergamon. HELBXICEP. A. and Rasm L. A. (1972) Rare earths and other trace elements in Apollo 15 samples The ApoUo 15 Lunur Samplea, (editors J. W. Chamberlain and C. Watkins), Lunar Science Institute, Houston. pp. 217-220. LAUL J. C., MORQ~ J. W., GANAPATEY R. and ANDER~E. (1971) Meteoritic material in lunar samples: characterization from trace elements. Proc. Second Lwmr Sci. Conf., Cfcochim. Coanwohim. Acta,SuppE. Vol. 2, pp. 1139-1158. M.I.T. Press. Mosaarr J. W., Kr&m~~tYzn., U., GBNILPATW. R. and ANDERSE. (1972) Volatile and siderophile elements in Apollo 14 and 15 rocks, Revimd Abe&a&, Third Lwmr Sci. Conf., (editor C. Watkins), pp. 555-557. Lunar Science Institute, Houston.
CkmhimIca et CoenoahhIcadota, 1075,Vol. 37.pp. 708to 710. Pergmon Press. Printedin NorthernIreland
The e&ct oflldo5gd x-rayil!radhtion anlithimn~~~~p\nr#diPcsssasedinX.B.F.an~ RO~EB W. LE KUTRE and =UNU T. mw9a School of Geology, University of Melbourne, Parkville, Viotoria 3052, Australia (Received 12 Septsmber1972; accepted in re&ed farm 16 October1972) Aktnct_-Prolonged irradiation by X-rays of lithium t&r&borate glass discs causes signiikxmt ohanges in countrates for certain elements e.g. Na and Mg decrease while Al, Si and P inorease. This effect is probably due to surfacs diffusionin the glass as grinding away about 10 pm of the surfaae of the disc restores the countrates to their original levels. Although no ohange in countrates will ever be noticed on individual glass discs undergoing routine analyssa, where irradiationtime is only 8 minute or so, a cloee watih must be kept on any specimensthat have been irradiated for more than a few tens of hours.
DUG extensive calibration and standardisation of a Siemens sequential X-ray speotrometer it was noticed that the countrates of some of the major elements on one of two lithium tetraborate reference standards had appreoiably changed. As the
xotes
SANDELLE. B. (1962) The beryllium content of igneous rocks. Qeochim. Cosmochim. acta 2, 211-216. SHALE D. R. and BERNOLD S. (1964) Distribution of beryllium in igneous rocks. U.S. Beol. Surv., Prof. Paper 501-B, 100-104. SEAWE D. R. and BERNOLD S. (1966) Beryllium content of volcanic rocks. U.S. Geol. Sure. Bull. 1214-C, 11. SIQKCNOLFI G. P. (19’70) Investigations into the deep levels of the continental crust: petrology and chemistry of the granulite facies terrains of Southern Bahia (Brazil). Atti Sot. Tosc. SC. Nat. &fern. A17, 327-341. SIOHMOLPI G. P. (1971) Investigations into deep crustal levels: fractionating effecta and geochemical trends related to high-grade metamorphism. f_Jwchim. Coemochim. Acta 35, 10061021. SIOEINOLIFI G. P. (1972) Determination of beryllium in standard rock samples by flameless A. A. spectroscopy. Atomic Absorption Newektter II, 96-98. SLEPNEYY. S. (1969) The characteristics of distribution of some rare elements in metamorphio rocks, granites, and rare metal pegmatites of the Sayan Mountains. Ueochemietry (USSR) (English Transl.) 4, 312-314. TAYLOR S. R. (1964) Abundance of chemical elements in the continental crust: a new table. Qeochim. Coemochim. Acta aS, 1273-1285. Oeochlmica et Coamochlmica Aeta,1973.Vol. 97, pp. 706to 708. Pergamon Pm.
Trace elements
in finesfrom
the
Apoh
PrIntedin Northern Ireland
15 deep dpill
PHILIP A. HELMKE, KAREN M. TELANDEB, CHARLES K. WEISS and L-Y A. BASEIN Department of Chemistry, University of Wisconsin-Madison, (Received 22 August 1972: accepted in rev&&form
53706, U.S.9.
10 October 1972)
Al&&--No systematic variations in concentrations with depth were found for lOtrace elements in samplea from the Apollo 15 deep drill. Presence of a sign&ant amount of KREEP is indiceted.
SAMPLESof fines ( < 1 mm) from the bottom of the Apollo 16 deep drill core and from each junction between the six 42.5 cm long segments of the drill stem were analyzed for Ag, Co, Cr, Cs, Cu, Ga, Hf, Rb, SC and Zn by neutron activation. Prooedures used were adapted from our earlier work (-KIN et al., 1970 ; ALLEN eb al., 1970). The samples weighed approximately 50 mg each ctnd were splits of approximately 2 g, sieved samples used for biomedical testing. The results of the analyses are shown in Fig. 1. The indicated analytical uncertainties are based mainly on counting statistics. The samples were subjected to a minimum of kndling in our laboratory prior to neutron irradiation. Each plastic vial was removed from its inner T&on@ bag and opened inside a cleaned stainless steel and luoite cabinet in an air atmosphere. The contents were transferred immediately into weighed, cleaned quartz tubes. The tubes were weighed with$he samples in them and sealed off. Exposure time between opening the plastic vials and sealing the quartz tubes ranged from 5 to 16 minutes. The samples were irradiated for 7 hours at a neutron flux of approximately lOls n/cmz/ sec.
707
Notee
The most striking feature of the results (Fig. 1) is the absence of signifknt variations in ooncentration for any element, within the limits of the analytical unoertainties, throughout the 240 cm depth of the drill sample and despite the considerable stratigraphy of the oared material (determined by X-radiography by G. Heiken and J. Lindsay). Variations in concentrations of So and Cu amounting to about 10 per cent and of Cr, Hf and Rb of up to 20 per oent were observed, but these variations are not oorrelated with each other. This suggests that either the regolith where the drill core was taken has been chemically homogenized by local events or that the drill did not penetrate through the last major blanket of material laid down at the site. The composition of the material from the drill differs signifkantly from that of surface fines 15601 and 16471 near Hadley Rille and Dune orater (HELBEKEand HasKIN, 1972). The oonoentrations of SC, Co and Ga in material from the deep drill are substantially lower (factors of 0.67 to 0.87) but those of Zn, Hf and Cr are about the same as in ties 16601 and 16471. The concentrations for all elements exceptGa (a little low) and Ag (high) fall within the ranges reported for fks from thether lunar missions.
3
z
moo2. 207 --I21)
2 14;::; % lmool ,239’ 23’
on3
0.l
!I0 ELEMENT=
rxiAmT,oN
loo
5 rpplry
Fig. 1. Concentrations for 10 trace elements in samplea from the Apollo 16 deep drill core have been plotted again& approximate depths in the drill atem. Sample numbere arc given beaide the depths.
The oonoentration range for Ag is well above that of about 10-30 ppb reported for ties from other Apollo missions (e.g., QmapaTrzv et aE.,1970; Lam, et a2., 1971; MOXUUN et a;Z.,1972). This implies that most of the Ag we observed is a oontaminant. The contamination may have ooourred in our laboratories. However, brazing materials used in the manufacture of the drill bit oontain Ag as a major oonstituent, along with Cu and Zn (L. Silver, private communication). The high values for Ag may thus have resulted from abrasion of the bit by the lunar material during drill@ The quantity of brasing material required to contaminate the sample sign&a&y with Ag is only about one-thousandth that required to contaminate the sample to the same degree with Cu or Zn.
708
Notes
The concentrations of Co and SC in the Gnes from the deep drill are lower (factors of O-7 and O-6) and those of Hf (factor of 1.7) and Rb and Cs (factor of about 10) are higher than the averages found for four ApoIIo 15 igneous rocks (unpubhshed data). This suggests the presence of a significant KREEP component with a composition similar to that of 12013 in the fines. Acknwkdgemmte-We thank the crew of the University of Wisoonsin nuolear reactor for irradiatingthe samples. We are grateful to Astronauts Scold and Ium for their special efforts that made these samples available. This work was supported in part by the National Aeronautics and Space Administration under grant NQL-50-002-148. REFERENCES ALLEN R. O., HasL. A., ANDEESON M. R. and MifLLzm0. (1970) Neutron activation analysis for 39 elements in small or precious geologic samples. J. Radioanal. Chetn. 6, 115-137. GANAPATHIT R., Rm R., hAY9 R., Lawn J. C. and ANDu.uaE. (1970) Trace elements in Apollo 11 lunar rooks: implication for meteorite influx and origin of moon. Proc. ApoZlu 11 Lunar Ski. Cmf., (editor A. A. Levinson), Vol. 2, 1117-I 142. Pergamon. HasL. A., ALLEN R. O., HELMEE P. A., PAETER T. P., ANDEESON M. A., KOWTEV R. L. and Zm K. A. (1970) Rare earths and other trace elements in Apollo 11 lunar samples. Proc. Apollo 11 Lunar Sci. Conf., (editor A. A. Levinson), Vol. 2, 1213-1231. Pergamon. HELBXICEP. A. and Rasm L. A. (1972) Rare earths and other trace elements in Apollo 15 samples The ApoUo 15 Lunur Samplea, (editors J. W. Chamberlain and C. Watkins), Lunar Science Institute, Houston. pp. 217-220. LAUL J. C., MORQ~ J. W., GANAPATEY R. and ANDER~E. (1971) Meteoritic material in lunar samples: characterization from trace elements. Proc. Second Lwmr Sci. Conf., Cfcochim. Coanwohim. Acta,SuppE. Vol. 2, pp. 1139-1158. M.I.T. Press. Mosaarr J. W., Kr&m~~tYzn., U., GBNILPATW. R. and ANDERSE. (1972) Volatile and siderophile elements in Apollo 14 and 15 rocks, Revimd Abe&a&, Third Lwmr Sci. Conf., (editor C. Watkins), pp. 555-557. Lunar Science Institute, Houston.
CkmhimIca et CoenoahhIcadota, 1075,Vol. 37.pp. 708to 710. Pergmon Press. Printedin NorthernIreland
The e&ct oflldo5gd x-rayil!radhtion anlithimn~~~~p\nr#diPcsssasedinX.B.F.an~ RO~EB W. LE KUTRE and =UNU T. mw9a School of Geology, University of Melbourne, Parkville, Viotoria 3052, Australia (Received 12 Septsmber1972; accepted in re&ed farm 16 October1972) Aktnct_-Prolonged irradiation by X-rays of lithium t&r&borate glass discs causes signiikxmt ohanges in countrates for certain elements e.g. Na and Mg decrease while Al, Si and P inorease. This effect is probably due to surfacs diffusionin the glass as grinding away about 10 pm of the surfaae of the disc restores the countrates to their original levels. Although no ohange in countrates will ever be noticed on individual glass discs undergoing routine analyssa, where irradiationtime is only 8 minute or so, a cloee watih must be kept on any specimensthat have been irradiated for more than a few tens of hours.
DUG extensive calibration and standardisation of a Siemens sequential X-ray speotrometer it was noticed that the countrates of some of the major elements on one of two lithium tetraborate reference standards had appreoiably changed. As the