Citation:

S0009-2541(01)00277-7

Name: (Table 1) Chemical composition and bulk densities of dolerites from ODP Hole 504B lower dikes
Published: 2001
License: https://creativecommons.org/licenses/by/3.0/

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

RIS Citation BibTeX Citation Text Citation Facebook TwitterShow Map Google Earth

Abstract:

Chemical interactions between seawater and the oceanic crust have been widely investigated during recent years. However, most of these studies concern the uppermost volcanic part of the crust. The contribution of the underlying sheeted dike complex to the global budget of the oceans is inferred solely from some ophiolite studies and from the 500-m high-level dike section of DSDP/ODP 504B which was drilled in 1981. Hole 504B is the only place where a continuous and long (1260 m) section in the sheeted dike complex has been cored, and it is now regarded as a reference section for the upper oceanic crust. Many petrological and chemical data from these dolerites are available, including the relative proportions of veins, extensively altered adjacent rocks, and less altered 'host-rocks'. For these three reasons, considering the entire dike section penetrated by Hole 504B is a unique chance to study chemical fluxes related to hydrothermal alteration of this part of the oceanic crust.

The calculation of any chemical flux implies knowledge of the chemical composition of the fresh precursor (protolith). Previously, mean compositions of glasses (=P1a) or basalts from the Hole 504B volcanics have been used as protoliths. In this paper, we calculate and discuss the use of various protoliths based on dolerites from Hole 504B. We show that the most adequate and realistic protolith is the mean of individual protoliths that we calculated from the acquisition, by automatic mode, of about 1000 microprobe analyses in each thin-section of dolerite from the Hole 504B lower dikes. Consequently, PFm is further used to calculate chemical fluxes in the dike section of Hole 504B.

The chemical compositions of the host-rocks adjacent to alteration halos tend to converge to that of PFm with depth, except for Fe2O3t and TiO2. Because the volume percent of alteration halos increases with depth, the total fluxes related to these halos increase with depth. This explains why the mean flux (host-rocks+halos+veins) of the upper dikes is roughly similar to the mean flux of the lower dikes. During the alteration of the entire Hole 504B dike section, the dolerites gained relatively large quantities of Fe2O3t (+4.0 g/100 cm**3) and released much SiO2 (-6.8 g/100 cm**3), CaO (-5.8 g/100 cm**3), and TiO2 (1.6 g/100 cm**3), and minor Al2O3 (-0.7 g/100 cm**3) and MgO (-0.7 g/100 cm**3). We show the importance of the choice of the protolith in the calculation of chemical budget, particularly for elements showing low flux values. In Hole 504B, the Mg uptake by the volcanics during low temperature alteration added to the Mg release by the dikes gives a net flux of -0.07x10**14 g/year. We propose that part of the Mg uptake by the oceanic crust, which is necessary to compensate the rivers input (-1.33x10**14 g/year), occurs in the underlying gabbros and/or in sections which are altered such as Trinity and Troodos ophiolites. Compared with ophiolites, fluxes calculated for elements other than Mg for the entire crust are generally similar (in tendency, if not in absolute value) to that we obtained from Hole 504B.

Project(s):

Ocean Drilling Program (ODP)

Coverage:

Latitude: 1.226900 * Longitude: -83.730300

Date/Time Start: 1993-03-04T18:00:00 * Date/Time End: 1993-03-06T04:55:00

Minimum DEPTH, sediment/rock: 1662.1 m * Maximum DEPTH, sediment/rock: 1916.5 m

Event(s):

148-504B * Latitude: 1.226900 * Longitude: -83.730300 * Date/Time Start: 1993-03-04T18:00:00 * Date/Time End: 1993-03-06T04:55:00 * Elevation: -3474.0 m * Penetration: 2111 m * Recovery: 9.58 m * Location: North Pacific Ocean * Campaign: * Basis: Joides Resolution * Method/Device: Drilling/drill rig (DRILL) * Comment: 23 cores; 110.6 m cored; 0 m drilled; 8.7 % recovery

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		Laverne, Christine	DSDP/ODP/IODP sample designation
3	Comment	Comment		Laverne, Christine
4	Density	Density	g/cm³	Laverne, Christine	Pycnometer (Micromeritics)
5	Silicon dioxide	SiO2	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
6	Titanium dioxide	TiO2	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
7	Aluminium oxide	Al2O3	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
8	Iron oxide, Fe2O3	Fe2O3	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
9	Iron oxide, Fe2O3	Fe2O3	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)	total Fe expressed as Fe2O3
10	Iron oxide, FeO	FeO	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
11	Manganese oxide	MnO	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
12	Magnesium oxide	MgO	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
13	Calcium oxide	CaO	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
14	Sodium oxide	Na2O	%	Laverne, Christine	Atomic absorption spectrometry (AAS)
15	Potassium oxide	K2O	%	Laverne, Christine	Atomic absorption spectrometry (AAS)
16	Phosphorus pentoxide	P2O5	%	Laverne, Christine	Inductively coupled plasma atomic emission spectroscope (ICP-AES)
17	Water in rock	H2O	%	Laverne, Christine		H2O+, structural part, similar to LOI
18	Water in rock	H2O	%	Laverne, Christine		H2O-
19	Sum	Sum	%	Laverne, Christine	Calculated

License:

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

Size:

480 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 Comment	4 Density [g/cm³] (Pycnometer (Micromeritics))	5 SiO2 [%] (Inductively coupled plasma at...)	6 TiO2 [%] (Inductively coupled plasma at...)	7 Al2O3 [%] (Inductively coupled plasma at...)	8 Fe2O3 [%] (Inductively coupled plasma at...)	9 Fe2O3 [%] (total Fe expressed as Fe2O3, ...)	10 FeO [%] (Inductively coupled plasma at...)	11 MnO [%] (Inductively coupled plasma at...)	12 MgO [%] (Inductively coupled plasma at...)	13 CaO [%] (Inductively coupled plasma at...)	14 Na2O [%] (Atomic absorption spectrometr...)	15 K2O [%] (Atomic absorption spectrometr...)	16 P2O5 [%] (Inductively coupled plasma at...)	17 H2O [%] (H2O+, structural part, simila...)	18 H2O [%] (H2O-)	19 Sum [%] (Calculated)
1662.1	148-504B-191R-1,6-10	alteration halo associated with vein	2.823	48.53	0.92	16.76	8.78	9.53	0.68	0.15	7.20	11.31	2.31	0.06	0.08	2.48	0.20	99.46
1662.1	148-504B-191R-1,6-10	fresher adjacent host-rock	2.941	48.71	0.90	15.80	5.97	9.65	3.32	0.17	8.12	12.56	1.75	0.06	0.06	1.58	0.34	99.34
1689.2	148-504B-194R-1,120-123	alteration halo associated with vein	2.731	47.84	0.78	15.71		10.88		0.17	8.33	10.59	2.14	0.13	0.08	2.14	0.32	99.11
1689.2	148-504B-194R-1,120-123	fresher adjacent host-rock	2.937	47.51	0.78	15.81	7.71	9.15	1.30	0.17	8.57	12.93	2.01	0.07	0.08	2.48	0.42	99.84
1686.6	148-504B-194R-1,84-87	patch of alteration	2.812	49.42	0.58	14.53	6.76	9.49	2.46	0.17	8.15	11.89	1.86	0.13	0.06	3.25	0.46	99.72
1686.6	148-504B-194R-1,84-87	fresher adjacent host-rock	2.906	48.44	0.87	14.99	7.16	9.89	2.46	0.17	8.34	12.81	1.89	0.09	0.08	1.44	0.16	98.90
1717.1	148-504B-198R-1,56-60			49.00	0.81	15.59	2.31	9.71	6.67	0.17	9.14	12.90	1.54	0.02	0.09	1.56	0.24	100.04
1720.5	148-504B-199R-1,14-16			48.67	0.75	15.21	6.72	9.32	2.35	0.16	9.63	12.73	1.69	0.06	0.07	1.80	0.50	100.34
1730.0	148-504B-200R-1,62-66			48.36	0.80	16.14	2.28	9.47	6.48	0.16	9.44	12.64	1.67	0.04	0.09	1.36	0.20	99.66
1733.4	148-504B-200R-2,101-104			48.70	0.77	15.75	6.98	9.06	1.88	0.16	8.87	12.97	1.67	0.11	0.08	1.68	0.46	100.08
1731.3	148-504B-200R-2,127-129			48.07	0.78	15.82	2.34	8.96	5.97	0.16	8.81	12.98	1.58	0.02	0.08	2.06	0.66	99.33
1737.4	148-504B-200R-4,42-45	alteration halo associated with vein	2.906	48.53	0.62	14.46	2.02	11.08	8.17	0.20	9.95	11.43	1.47	0.04	0.07	1.87	0.58	99.41
1737.4	148-504B-200R-4,42-45	fresher adjacent host-rock	2.925	47.89	0.74	15.87	1.69	9.23	6.80	0.16	9.48	12.79	1.61	0.04	0.08	1.74	0.16	99.05
1768.9	148-504B-207R-1,44-47			49.18	1.02	14.03	2.18	10.82	7.79	0.18	8.60	12.54	1.83	0.05	0.10	1.02	0.28	98.80
1778.7	148-504B-208R-1,18-21			48.23	0.77	16.20	2.45	9.30	6.18	0.16	9.09	13.18	1.70	0.05	0.08	1.48	0.32	99.89
1780.4	148-504B-208R-1,56-61	alteration halo associated with vein	2.897	47.25	0.81	14.66	1.69	13.28	10.45	0.22	8.52	10.04	1.80	0.04	0.09	2.24	0.32	98.13
1780.4	148-504B-208R-1,56-61	fresher adjacent host-rock	2.977	48.85	0.86	15.32	2.04	9.58	6.81	0.16	8.42	13.07	1.60	0.03	0.08	1.72	0.38	99.34
1785.6	148-504B-208R-2,76-81			48.38	0.87	16.02	2.68	9.41	6.07	0.16	8.39	12.93	1.70	0.04	0.09	1.60	0.38	99.31
1789.4	148-504B-209R-1,66-69	alteration halo associated with vein	2.767	47.73	0.75	16.83	2.20	9.81	6.86	0.16	7.86	11.63	1.72	0.01	0.08	2.36	0.58	98.77
1789.4	148-504B-209R-1,66-69	fresher adjacent host-rock	2.896	49.17	0.84	16.74	1.23	7.90	6.01	0.15	8.17	13.73	1.87	0.02	0.09	1.32	0.20	99.54
1793.3	148-504B-209R-2,108-111	patch of alteration		48.61	0.75	16.01	2.07	8.35	5.66	0.15	8.78	13.58	1.80	0.02	0.09	1.60	0.20	99.32
1793.3	148-504B-209R-2,108-111	fresher adjacent host-rock		48.47	0.89	15.78	1.64	9.16	6.78	0.16	8.47	12.76	1.69	0.02	0.10	1.40	0.18	98.34
1812.1	148-504B-212R-1,61-65	alteration halo associated with vein	3.076	47.90	0.90	15.26	1.82	10.11	7.47	0.17	8.81	12.74	1.76	0.02	0.09	1.24	0.18	97.76
1812.1	148-504B-212R-1,61-65	fresher adjacent host-rock	2.993	47.90	0.89	15.19	2.95	10.05	6.40	0.17	8.57	12.72	1.78	0.04	0.09	1.72	0.66	99.08
1875.7	148-504B-221R-1,63-67			46.35	1.04	15.84	2.68	8.44	5.19	0.14	8.61	13.52	1.92	0.02	0.12	4.06	0.80	100.29
1885.3	148-504B-222R-1,64-68			45.80	0.91	15.42	3.93	10.17	5.63	0.17	9.11	11.99	1.34	0.02	0.10	4.02	0.80	99.21
1916.5	148-504B-225R-1,126-129	alteration halo associated with vein	2.898	49.25	0.82	15.10	1.69	10.30	7.76	0.16	8.57	12.53	1.69	0.05	0.09	1.24	0.20	99.15
1916.5	148-504B-225R-1,126-129	fresher adjacent host-rock	2.991	48.18	0.90	15.26	2.89	9.62	6.07	0.16	8.68	12.60	1.72	0.02	0.08	1.98	0.48	99.02