Citation:

0009-2541(82)90050-X

Name: (Table 1) Chemical and lithological composition of rocks from DSDP Hole 465A
Published: 1982
License: https://creativecommons.org/licenses/by/3.0/

Always quote citation above when using data! You can download the citation in several formats below.

Published: 1982 (exact date unknown) • DOI registered: 2008-08-05

RIS Citation BibTeX Citation Text Citation ShareShow Map Google Earth

Abstract:

Uranium and thorium are concentrated in Cretaceous limestone, chert, ash, basalt, and other rock types at Deep Sea Drilling Project Site 465 located on the southern Hess Rise in the central North Pacific. U concentrations, up to 194 ppm on a carbonate-free basis, are among the highest recorded for any deep-sea deposits. U was initially derived from seawater and concentrated by absorption on terrigenous (humic) organic matter in limestone in a shallow marine environment. U and Th were probably concentrated further by low-temperature hydrothermal fluids emanating from the basaltic basement. Mainly montmorillonite, an alteration product of basalt and ash, and organic matter in sedimentary rocks acted as hosts for U and Th.

The unique combination of sediments rich in humic organic matter, abundant smectite in altered ash and basalt, and warm hydrothermal solutions provided the necessary conditions for migration and concentration of U and Th. To better understand the conditions limiting the migrating and concentration of U and Th, other rocks deposited during the ocean-wide Cretaceous anoxic events should be analyzed for these elements.

Project(s):

Deep Sea Drilling Project (DSDP)

Coverage:

Latitude: 33.820500 * Longitude: 178.919000

Date/Time Start: 1978-08-23T00:00:00 * Date/Time End: 1978-08-23T00:00:00

Minimum DEPTH, sediment/rock: 392.80 m * Maximum DEPTH, sediment/rock: 419.50 m

Event(s):

62-465A * Latitude: 33.820500 * Longitude: 178.919000 * Date/Time: 1978-08-23T00:00:00 * Elevation: -2161.0 m * Penetration: 476 m * Recovery: 98.9 m * Location: North Pacific/CONT RISE * Campaign: * Basis: Glomar Challenger * Method/Device: Drilling/drill rig (DRILL) * Comment: 43 cores; 408.5 m cored; 9.5 m drilled; 24.2 % recovery

Comment:

In the sample 465A-40-1, 145 (calcareous ash / sulfide-rich fraction) contents of major oxides were measured by quantitative emission spectroscopy; in the samples 465A-40-2, 62 (altered ash) and 465A-40-2, 62 (altered ash, <1 µm fraction) contents of major oxides were measured by semi-quantitative emission spectroscopy.

Parameter(s):

#	Name	Short Name	Unit	Principal Investigator	Method/Device	Comment
1	DEPTH, sediment/rock	Depth sed	m			Geocode
2	Sample code/label	Sample label		Hein, James R	DSDP/ODP/IODP sample designation
3	Rock type	Rock		Hein, James R
4	Lithology/composition/facies	Lithology		Hein, James R
5	Minerals	Minerals		Hein, James R		major
6	Minerals	Minerals		Hein, James R		moderate
7	Minerals	Minerals		Hein, James R		minor
8	Minerals	Minerals		Hein, James R		trace
9	Silicon dioxide	SiO2	%	Hein, James R	X-ray fluorescence on pressed powder
10	Aluminium oxide	Al2O3	%	Hein, James R	X-ray fluorescence on pressed powder
11	Titanium dioxide	TiO2	%	Hein, James R	X-ray fluorescence on pressed powder
12	Iron oxide, Fe2O3	Fe2O3	%	Hein, James R	X-ray fluorescence on pressed powder	total Fe as Fe2O3
13	Magnesium oxide	MgO	%	Hein, James R	X-ray fluorescence on pressed powder
14	Calcium oxide	CaO	%	Hein, James R	X-ray fluorescence on pressed powder
15	Sodium oxide	Na2O	%	Hein, James R	X-ray fluorescence on pressed powder
16	Potassium oxide	K2O	%	Hein, James R	X-ray fluorescence on pressed powder
17	Phosphorus pentoxide	P2O5	%	Hein, James R	X-ray fluorescence on pressed powder
18	Barium oxide	BaO	%	Hein, James R	X-ray fluorescence on pressed powder
19	Sulfite	[SO3]2-	%	Hein, James R		3 by difference on barite-rich samples
20	Manganese	Mn	mg/kg	Hein, James R	X-ray fluorescence on pressed powder
21	Loss on ignition	LOI	%	Hein, James R		at 1050°C
22	Sum	Sum	%	Hein, James R	Calculated
23	Carbon, organic, total	TOC	%	Hein, James R	Element analyser CHN, LECO WR-12
24	Calcium carbonate	CaCO3	%	Hein, James R	Element analyser CHN, LECO WR-12
25	Uranium	U	mg/kg	Hein, James R	Element analysis, neutron activation (NAA)
26	Thorium	Th	mg/kg	Hein, James R	Element analysis, neutron activation (NAA)	differences in detection limits are due to dilutions required to complete the analysis

License:

Creative Commons Attribution 3.0 Unported (CC-BY-3.0)

Size:

278 data points

Data

Download dataset as tab-delimited text — use the following character encoding:

1 Depth sed [m]	2 Sample label (DSDP/ODP/IODP sample designation)	3 Rock	4 Lithology	5 Minerals (major)	6 Minerals (moderate)	7 Minerals (minor)	8 Minerals (trace)	9 SiO2 [%] (X-ray fluorescence on pressed...)	10 Al2O3 [%] (X-ray fluorescence on pressed...)	11 TiO2 [%] (X-ray fluorescence on pressed...)	12 Fe2O3 [%] (total Fe as Fe2O3, X-ray fluo...)	13 MgO [%] (X-ray fluorescence on pressed...)	14 CaO [%] (X-ray fluorescence on pressed...)	15 Na2O [%] (X-ray fluorescence on pressed...)	16 K2O [%] (X-ray fluorescence on pressed...)	17 P2O5 [%] (X-ray fluorescence on pressed...)	18 BaO [%] (X-ray fluorescence on pressed...)	19 [SO3]2- [%] (3 by difference on barite-ric...)	20 Mn [mg/kg] (X-ray fluorescence on pressed...)	21 LOI [%] (at 1050°C)	22 Sum [%] (Calculated)	23 TOC [%] (Element analyser CHN, LECO WR-12)	24 CaCO3 [%] (Element analyser CHN, LECO WR-12)	25 U [mg/kg] (Element analysis, neutron act...)	26 Th [mg/kg] (differences in detection limi...)
392.80	465A-38-2, 80	chert	black chert	quartz			pyroxene, smectite	90.10	4.36	<0.02	0.07	0.13	0.45	<0.15	0.05	0.06			<200	3.15	98.37	0.96	2.0	6.21	<5.0
392.85	465A-38-2, 85	limestone	gray limestone	calcite			quartz	3.01	1.09	<0.02	0.16	0.74	49.20	0.46	0.22	0.19			<200	42.40	97.47	2.94	88.7	20.80	<8.8
400.91	465A-39-1, 91	limestone	gray limestone	calcite			plumbo-jarosite?, quartz															2.33	93.5	12.60	<7.1
410.00	465A-40-1, 50	limestone	gray-green limestone	calcite		dolomite	quartz, plumbo-jarosite?	4.44	1.51	<0.02	0.15	1.03	48.30	0.50	0.24	0.36			900	39.90	96.43	2.41	89.0	20.80	<7.5
410.95	465A-40-1, 145	ash		dolomite	plagioclase	high-Mg calcite pyrite, barite, quartz	smectite															1.78	32.7	9.83	15.6
410.95	465A-40-1, 145	ash	calcareous ash / barite-rich fraction					16.53	5.22	0.27	1.95	5.71	9.76	1.42	0.97	0.10	29.8	13.91	400	14.31	99.95
410.95	465A-40-1, 145	ash	calcareous ash / sulfide-rich fraction					<21.40	3.02	0.10	>28.59	3.98	7.00	0.96	1.18	<0.05			340
410.95	465A-40-1, 145	ash	calcareous ash / dolomite-rich fraction
411.10	465A-40-2, 10	pyrite	dark-gray pyrite layer	pyrite	quartz, plagioclase	dolomite, calcite, barite		21.90	5.75	0.10	41.06	0.69	2.71	1.79	2.02	<0.05		3.21	240	20.97	100.20	0.16	7.6	3.73	8.1
411.29	465A-40-2, 29	dolomite	gray-green clastic dolomite	barite	calcite	K-feldspar, quartz, pyrite		7.89	2.77	0.09	1.73	4.97	14.20	0.66	0.24	<0.05	33.7	15.15	1000	18.45	99.85	0.93	29.2	0.78	5.9
411.62	465A-40-2, 62	ash	altered ash	microcline	smectite, quartz, plagioclase	pyrite, pyroxene, barite, opal-CT	apatite, illite	59.90	14.55	0.33	2.57	2.98	0.48	3.77	3.61	0.12			370			0.01	0.4	7.65	35.6
411.62	465A-40-2, 62	ash	altered ash, <1 µm fraction	montmorillonite				59.90	15.12	0.32	1.72	4.97	0.13	3.64	0.60	0.09			<200					4.79	29.9
411.64	465A-40-2, 64	ash	gray laminated ash	plagioclase, smectite	quartz, pyroxene																			6.84	30.1
411.94	465A-40-2, 94	ash	yellow-to-gray altered ash	plagioclase	jarosite, pyrite, smectite	quartz	illite?	42.24	13.78	0.76	8.39	1.98	1.22	2.70	2.83	0.15	8.0	2.90	<200	15.09	100.04	0.00	0.6	5.23	14.3
412.36	465A-40-2, 136	volcanic breccia	gray m-b basalt breccia	plagioclase	calcite, smectite, pyroxene	pyrite	apatite?	54.50	17.60	0.98	4.07	3.25	2.29	3.52	2.86	0.18			<200	10.00	99.25	0.00	1.6	4.54	13.3
419.50	465A-41-1, 50	volcanic breccia	gray m- b basalt breccia	plagioclase	pyroxene	smectite, pyrite, quartz	apatite?	56.70	18.30	0.97	3.53	2.43	2.06	4.61	3.01	0.27			<200	7.29	99.17	<0.01	0.7	4.07	10.9