# Burial Lake, Alaska 37,000 Year Geochemical Data
#----------------------------------------------------------------------- 
#                World Data Service for Paleoclimatology, Boulder 
#                                  and 
#                     NOAA Paleoclimatology Program 
#             National Centers for Environmental Information (NCEI)
#----------------------------------------------------------------------- 
# 
# NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. 
# If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. 
#
# Online_Resource: https://www.ncdc.noaa.gov/paleo/study/19240 
# Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/northamerica/usa/alaska/burial2015bsi.txt
#
# Original_Source_URL: 
# 
# Description/Documentation lines begin with #
# Data lines have no #
#
# Archive: Paleolimnology
#
# Parameter_Keywords: Geochemistry
#--------------------
# Contribution_Date
#	Date: 2015-09-25
#--------------------
# Title
#	Study_Name: Burial Lake, Alaska 37,000 Year Geochemical Data
#--------------------
# Investigators
# 	Investigators: Finkenbinder, M.S.; Abbott, M.B.; Finney, B.P.; Stoner, J.S.; Dorfman, J.M.
#--------------------
# Description_and_Notes
#	Description: Geochemical data from Burial Lake, Alaska for the last 37,000 cal yr BP. Data include dry bulk density, 
#	percent organic matter, percent biogenic silica, magnetic susceptibility, carbon to nitrogen (C/N) mass ratios, 
#	bulk sediment organic matter carbon (d13C) and nitrogen (d15N) isotopes, and elemental abundances from scanning XRF analysis.  
#
#--------------------
# Publication 
#	Authors: M.S. Finkenbinder, M.B. Abbott, B.P. Finney, J.S. Stoner, J.M. Dorfman
#	Published_Date_or_Year: 2015-10-15
#	Published_Title: A multi-proxy reconstruction of environmental change spanning the last 37,000 years from Burial Lake, Arctic Alaska
#	Journal_Name: Quaternary Science Reviews
#	Volume: 126
#	Edition: 
#	Issue: 
#	Pages: 227-241
#	Report_Number: 
#	DOI: 10.1016/j.quascirev.2015.08.031
#	Online_Resource: http://www.sciencedirect.com/science/article/pii/S0277379115300974
#	Full_Citation: 
#	Abstract: Sediment cores from Burial Lake located in the western Brooks Range in Arctic Alaska record paleoenvironmental changes that span the last 37,000 calendar years before present (cal yr BP). We identified four distinct lithologic subunits based on physical properties (dry bulk density, magnetic susceptibility), sediment composition, and geochemical proxies (organic matter, biogenic silica, C/N, organic matter d13C and d15N, and elemental data from scanning X-ray fluorescence). The multi-proxy approach and relatively high temporal resolution (at multi-decadal to centennial time scales) of our proxy analysis, compared with previous studies of intermediate water depth cores from Burial Lake, provide new insights into the paleoenvironmental history of the region spanning the period prior to the Last Glacial Maximum. Relatively high lake-levels and gradually decreasing in-lake and terrestrial productivity occur during the mid-Wisconsin interstadial from 37,200 to 29,600 cal yr BP. The subsequent period is defined by falling and lower lake-levels with decreasing effective-moisture, windier conditions, and sustained low aquatic productivity throughout the LGM between 29,600 and 19,600 cal yr BP. The last deglaciation that commenced by 19,600 cal yr BP is characterized by gradual changes in several sediment physical and geochemical proxies, including increasing C/N ratios and terrestrial productivity, decreasing magnetic susceptibility and clastic sediment flux, along with rising and relatively higher lake-levels. A decrease in aeolian activity after 16,500 cal yr BP is inferred from the appearance of fine (very fine sandy silt) sediment, compared to coarse sediments through the LGM and last deglaciation. The highest levels of terrestrial inputs along with increasing and variable aquatic productivity occur during the Lateglacial to early Holocene interval between 16,500 and 8800 cal yr BP. The absence of multi-proxy evidence for a strong climatic reversal during the Younger Dryas from Burial Lake sediments contrasts with some paleorecords showing cooler temperatures and/or dry conditions in northern Alaska at this time. Peak levels of sediment organic content and terrestrial productivity at Burial Lake between 10,500 and 9900 cal yr BP coincide with the early Holocene summer insolation maxima, which likely represents summertime warming and an enhanced flux of watershed derived organic matter from permafrost degradation. The remainder of the Holocene (since 8800 cal yr BP) at Burial Lake is characterized by relatively high and stable lake levels, landscape stabilization, and relatively high and variable levels of aquatic productivity.
#------------------
# Funding_Agency 
#	Funding_Agency_Name: National Science Foundation 
#	Grant: NSF-ARC 0909545
#------------------
# Site_Information 
#	Site_Name: Burial Lake
#	Location: North America>United States Of America>Alaska
#	Country: United States Of America 
#	Northernmost_Latitude: 68.43
#	Southernmost_Latitude: 68.43
#	Easternmost_Longitude: -159.17
#	Westernmost_Longitude: -159.17
#	Elevation: 460 m  
#------------------
# Data_Collection   
#	Collection_Name: Burial2015BSi
#	Earliest_Year: 37163
#	Most_Recent_Year: -30 
#	Time_Unit: Cal. Year BP
#	Core_Length: m
#	Notes: 
#------------------
# Chronology_Information
#	Chronology: 
# 
# Accelerator Mass Spectrometry Radiocarbon ages for Burial Lake, Alaska
# 
# Sample ID	Core-Drive	Drive Depth	Total Depth	Material	14C Age	Error	Calib 6.0 Age (2Sigma)	notes	
# (UCIAMS #)		(cm)	(cm)		(yr BP)	(yr)	(yr BP)	
# 								
# 89197	A10-D1	45.0	45.0	plant material	2535	30	2493 - 2745	
# 109361	A10-D1	66.5	66.5	wood	3635	25	3872 4074	
# 116878	A10-D1	87.5	87.5	plant material	4910	90	5470 - 5896	
# 89198	A10-D1	111.0	111.0	plant material	6345	25	7174 - 7410	
# 109362	A10-D1	141.5	141.5	wood	8850	110	9564 - 10205	
# 89199	A10-D2	84.0	166.0	plant material	9760	40	11134 - 11244	
# 89200	A10-D3	54.0	173.5	seed	10085	45	11398 - 11959	
# 109363	A10-D5	35.5	359.5	plant material	14590	550	16570 - 18903	* rejected from age model.
# 89201	A10-D7	29.0	553.0	seed	25300	510	29173 31074	
# 89121	A10-D8	35.5	636.5	wood	32150	240	35699 - 37342	
# 89122	C10-D3	45.0	219.0	wood	13670	30	16657 - 16978	
# 89123	C10-D7	64.0	598.0	plant material	31290	300	35085 - 36475	* rejected from age model.
# 
# 	
#----------------	
# Variables 
#
# Data variables follow are preceded by "##" in columns one and two.
# Data line variables format:  Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) 
#
## depth_cm	depth, , , cm, , , , ,N
## age_calBP	age, , , calendar years before present, , , , ,N
## %bio-si	Biogenic Silica, , ,  percent, , paleolimnology, , ,N 
#
#----------------
# Data:
# Data lines follow (have no #)
# Data line format - tab-delimited text, variable short name as header
# Missing Values:  
# Burial Lake A-10/C-10 composite core Biogenic Silica 
# 
depth_cm	age_calBP	%bio-si	
0.5	-30	12.36
2.5	89	10.59
4.5	209	11.88
6.5	329	12.55
8.5	448	11.99
10.5	568	10.64
12.5	687	11.55
14.5	807	11.34
16.5	926	13.06
18.5	1046	13.23
20.5	1166	10.92
22.5	1285	10.63
24.5	1405	7.53
26.5	1524	9.14
28.5	1644	12.13
30.5	1763	13.05
32.5	1883	12.63
34.5	2002	15.13
36.5	2122	13.98
38.5	2242	12.56
40.5	2361	11.92
42.5	2481	10.14
44.5	2600	11.27
46.5	2722	13.54
48.5	2846	13.70
50.5	2969	15.77
52.5	3092	16.27
54.5	3215	14.53
56.5	3338	15.78
58.5	3461	12.90
60.5	3584	8.85
62.5	3707	8.77
64.5	3830	7.67
66.5	3953	9.11
68.5	4116	11.69
70.5	4279	12.24
72.5	4442	14.59
74.5	4605	17.02
76.5	4767	16.38
78.5	4930	13.45
80.5	5093	13.47
82.5	5256	9.95
84.5	5419	10.18
86.5	5582	9.58
88.5	5732	11.37
90.5	5869	11.37
92.5	6006	12.16
94.5	6144	13.37
96.5	6281	13.36
98.5	6418	11.83
100.5	6555	8.80
102.5	6693	9.54
104.5	6830	10.02
106.5	6967	10.88
108.5	7105	13.02
110.5	7242	12.68
112.5	7406	9.15
114.5	7580	8.68
116.5	7753	8.05
118.5	7927	10.17
120.5	8100	10.36
122.5	8274	9.37
124.5	8447	9.00
126.5	8621	9.22
128.5	8794	8.85
130.5	8968	7.38
132.5	9141	6.87
134.5	9315	8.43
136.5	9488	8.83
138.5	9661	7.76
140.5	9835	7.67
142.5	9974	6.01
144.5	10078	6.79
146.5	10181	6.41
148.5	10285	6.59
150.5	10389	6.34
152.5	10493	4.44
154.5	10597	4.13
156.5	10701	3.98
158.5	10805	4.91
160.5	10909	7.27
162.5	11013	8.65
164.5	11117	4.98
166.5	11225	4.95
168.5	11348	3.16
170.5	11470	7.03
172.5	11592	9.86
174.5	11767	9.33
176.5	11994	7.85
178.5	12221	8.86
180.5	12448	5.34
182.5	12675	5.35
184.5	12902	7.95
186.5	13129	12.53
188.5	13356	10.52
190.5	13583	7.50
192.5	13810	7.15
194.5	14037	4.00
196.5	14264	3.43
198.5	14491	2.58
200.5	14718	2.89
202.5	14944	2.89
204.5	15171	2.85
206.5	15398	3.74
208.5	15625	2.71
210.5	15852	2.39
212.5	16079	2.13
214.5	16306	1.12
216.5	16533	0.87
218.5	16760	0.88
221.5	16916	2.43
223.5	16996	0.96
225.5	17076	1.41
227.5	17155	0.95
229.5	17235	0.88
231.5	17314	1.18
233.5	17394	1.05
235.5	17474	1.69
237.5	17553	2.30
239.5	17633	1.98
241.5	17712	2.07
243.5	17792	2.02
245.5	17871	1.74
247.5	17951	1.87
249.5	18031	1.67
251.5	18110	1.73
253.5	18190	1.96
255.5	18269	1.99
257.5	18349	1.71
259.5	18429	1.33
261.5	18508	1.23
263.5	18588	1.28
265.5	18667	1.73
267.5	18747	1.32
269.5	18827	1.35
271.5	18906	1.29
273.5	18986	1.18
275.5	19065	1.15
277.5	19145	1.52
279.5	19224	1.54
281.5	19304	1.71
283.5	19384	1.69
285.5	19463	1.80
287.5	19543	1.90
289.5	19622	1.93
291.5	19702	1.56
293.5	19782	1.24
295.5	19861	1.09
297.5	19941	1.20
299.5	20020	1.04
301.5	20100	1.37
303.5	20180	1.59
305.5	20259	1.99
307.5	20339	1.89
309.5	20418	1.74
311.5	20498	1.70
313.5	20577	1.60
315.5	20657	1.74
317.5	20737	1.72
319.5	20816	1.70
321.5	20896	1.59
323.5	20975	1.70
324.5	21015	1.92
326.5	21095	2.20
328.5	21174	2.48
330.5	21254	2.16
332.5	21334	2.06
334.5	21413	1.87
336.5	21493	2.03
338.5	21572	2.05
340.5	21652	1.93
342.5	21732	1.67
344.5	21811	1.64
346.5	21891	1.49
348.5	21970	1.80
350.5	22050	1.53
352.5	22129	1.62
354.5	22209	1.56
356.5	22289	1.35
358.5	22368	1.50
360.5	22448	1.24
364.5	22607	1.21
368.5	22766	2.09
372.5	22925	1.73
376.5	23085	1.51
380.5	23244	1.70
384.5	23403	1.60
388.5	23562	1.35
392.5	23721	1.11
396.5	23880	1.28
400.5	24040	1.35
404.5	24199	1.44
408.5	24358	1.18
412.5	24517	1.14
416.5	24676	1.07
420.5	24836	1.91
422.5	24915	1.59
424.5	24995	0.92
428.5	25154	0.76
432.5	25313	0.87
436.5	25472	0.72
440.5	25631	0.98
444.5	25791	1.07
448.5	25950	1.06
452.5	26109	1.15
456.5	26268	1.11
460.5	26427	1.06
464.5	26586	1.72
468.5	26746	1.31
472.5	26905	1.14
476.5	27064	1.20
480.5	27223	1.17
484.5	27382	1.20
488.5	27542	1.09
492.5	27701	0.99
496.5	27860	1.33
500.5	28019	1.15
504.5	28178	1.23
508.5	28337	1.24
512.5	28497	1.10
516.5	28656	0.83
520.5	28815	0.84
522.5	28895	1.01
524.5	28974	1.30
528.5	29133	1.19
532.5	29292	1.05
536.5	29452	1.11
540.5	29611	2.13
544.5	29770	2.36
548.5	29929	2.82
552.5	30088	1.47
556.5	30474	1.10
560.5	30892	1.05
564.5	31310	0.96
568.5	31728	0.86
572.5	32146	1.17
576.5	32564	1.45
580.5	32982	1.37
584.5	33400	1.31
588.5	33818	1.39
592.5	34236	1.45
596.5	34655	2.13
598.5	34864	1.96
601.5	35177	1.70
605.5	35595	1.34
609.5	35769	1.92
613.5	35909	1.26
617.5	36048	1.06
621.5	36187	0.96
625.5	36327	1.24
629.5	36466	0.99
633.5	36605	0.99
637.5	36745	1.54
641.5	36884	1.83
645.5	37023	3.07
649.5	37163	1.86