Current Browsing: Geology


WATER: Dataset of the total station measurements at the super site around the Dayekou Guantan forest station

The data set is based on the geodetic coordinate data and other auxiliary data of the corner points of 16 subsamples of super sample plots, the setting points of lidar base station of the foundation and the base points of each tree trunk measured by the total station. The data acquisition time of total station is from June 3, 2008 to June 12, 2008, which is divided into two groups. One total station is used respectively, with the models of topcon602 and topcon7002. A total of 1468 Picea crassifolia trees in the super sample plot were measured, and all the corner points of the sub sample plot and the top points of the stake set on the base station of lidar were located. These positioning results are the main data content of the dataset. In addition, on June 3, 2008, June 4, 2008, June 6, 2011, the differential GPS z-max was used to locate all the stake vertices. By manually measuring the height of each stake, the height of the surface under the stake was calculated, and finally the three-dimensional coordinate position of the surface of each tree and the topographic map of super sample plot were generated. These data constitute the secondary data of the dataset. This data set can provide detailed ground observation data for the establishment of real three-dimensional forest scene, the development and correction of various three-dimensional forest remote sensing models, and ground validation data for the extraction of airborne lidar forest parameters.

2020-03-10

WATER: Dataset of differential global position system (DGPS) measurements at the super site around the Dayekou Guantan forest station (2008)

The super sample plot is composed of 16 sub samples. In order to locate each tree in the sample plot and facilitate the location of the base station point for ground-based radar observation, it is necessary to measure the geodetic coordinates of the sub sample plot corner point and the preset base station point for ground-based radar. The location of these points and each tree is measured by total station. Because the total station measures relative coordinates, in order to obtain geodetic coordinates, it is necessary to use differential GPS (DGPS) to measure at least one reference point around the super sample plot with high precision. In addition, we also use DGPS to observe the geodetic coordinates of all corner points of the subsample, and the measurement results can form the verification of the total station measurement results. The data set is based on all the positioning results measured by DGPS, excluding the positioning results of total station. The measurement time is from June 1 to 13, 2008, using the French Thales differential GPS measurement system, model z-max. The observation method is to use two GPS receivers for synchronous static measurement, one is the base station, which is set next to Gansu Water Conservation Forest Research Institute (the WGS geodetic coordinate of the base station is a first-class benchmark introduced from Zhangye City through multi station observation using z-max). The other is the mobile station, which is placed on the observation point of super sample plot. The observation time of each point varies from 10, 15, 20, 25, 30 minutes. The specific time depends on the satellite signal. The signal difference time is measured for several minutes more. Finally, the final positioning result is obtained by using the processing software of the instrument. WGS geodetic coordinate system is used for the positioning results. Firstly, six temporary control points were measured in the open area next to the super sample plot, providing reference points for the total station to measure the position of trees in the super sample plot. Then, flow stations were set up on each corner of 16 sub plots of super plot, and the coordinates of corner points were measured, and 41 observation points were obtained. The dataset stores the positioning results of these 47 points. This data is only for project use and not for external sharing.

2020-03-09

Lithologic data of shallow drilling formation in the middle reaches of Heihe River

Seven boreholes were drilled in the middle reaches of Heihe River. According to the sedimentary characteristics, the lithology of different layers of each borehole was described.

2020-03-08

Paleomagnetic data from the lunpola basin

The Lunpola Basin in the central Tibetan Plateau is situated along the southern margin of the east-west stretched Banggong-Nujiang suture belt between the Qiangtang Terrane and the Lhasa Terrane. The thick and continuous Cenozoic sediments in the basin can provide great potential for understanding the tectonic uplift, paleoaltimetry, erosion and depositional history of the Tibetan Plateau and climate environmental evolution. However, the study of geologic and climatic changes has been hindered by poor age constraints on the Cenozoic sedimentary sequence in the Lunpola Basin, especially its upper part with typical lacustrine oil shale sediments due to the discontinuous or unexposed outcrop caused by erosion or weathering. In this study, we investigated a 658 m-thick Cenozoic continuous lacustrine sedimentary section, Lunpori, from the upper sequence of the central basin. We found two layers of tuffs in this section and then carried out detailed paleomagnetic measurements. Constrained by tie points of U-Pb zircon ages, the observed magnetic zones are well correlated with chrons C5Bn.2n to C6AAn of the Geomagnetic Polarity Time Scale, yielding ages of ~21.2 to 15 Ma for the section. Lithofacies, pollen and fossil records suggest a relative temperate, humid climate prevailing in the Lunpola Basin during the period of Dingqinghu Formation, indicating that the Indian monsoon occurred before ~26 Ma.Through paleomagnetic analysis and testing of fluvial and lacustrine facies strata in Lumpola Basin since Miocene, 22Ma-15Ma magnetic stratigraphic chronology has been obtained.

2019-10-21

WATER: Dataset of surface roughness measurements in the E’pu foci experimental area during the pre-observation period

The dataset of surface roughness measurements was obtained in No. 1 and 2 quadrates of the E’bao foci experimental area during the pre-observation period. Both the quadrates were divided into 3×3 subsites, with each one spanning a 30×30 m2 plot. With the roughness board 110cm long and the measuring points distance 1cm, the samples were collected along the strip from south to north and from east to west, respectively. The coordinates of the sample would be got with the help of ArcView; and after geometric correction, surface height standard deviation (cm) and correlation length (cm) could be calculated based on the formula listed on pages 234-236, Microwave Remote Sensing, Vol. II. The original photos of each sampling point, surface height standard deviation (cm) and correlation length (cm) were archived. The roughness data were initialized by the sample name, which was followed by the serial number, the name of the file, standard deviation and correlation length. Each .txt file is matched with one sample photo and standard deviation and correlation length represent the roughness. In addition, the length of 101 needles is also included for further validation.

2019-09-15

WATER: Dateset of the ground-based RPG-8CH-DP microwave radiometer observations in the Biandukou foci experimental area

The dateset of the ground-based RPG-8CH-DP microwave radiometer observations was obtained in the Biandukou foci experimental area from Mar. 14 to 17, 2008. Observation items included the brightness temperature by the ground-based microwave radiometer (18.7GHz and 36.5GHz), the soil temperature by the thermal resistor, the gravimetric soil moisture by the microwave drying method, and the surface roughness by the grid board. The wheat stubble land (38°15'44.13"N, 100°55'35.34"E) was chosen for continuous observations from 11:00 to 24:00 on Mar. 14, with the incidence 20°-70° and the step length 5°. The rape stubble land (38°15'23.17"N, 100°58'37.84"E) was chosen for continuous observations from 10:00 to 21:30 on Mar. 16, with the incidence 20°-70° and the step length 5°. The deep plowed land (38°18'8.28"N, 101° 3'27.22"E) was chosen for short time observations from 17:26 to 19:20 on Mar. 17, with the azimuth angle 240°-300° and the step length 10°, the incidence 40°-70° and the step length 5°. The brightness temperature was archived as .BRT and .txt files (the ASCII format). Each row in .txt was listed by year, month, date, hour, minute, second, 6.925GHz (h), 6.925GHz (v), 10.65GHz (h), 10.65GHz (v) , 18.7GHz (h), 18.7GHz (v), 36.5GHz (h), 36.5GHz (v), the elevation angle, and the azimuth angle. Values for 6.925GHz and 10.65GHz were zero due to malfunction. The roughness data were obtained by the grid board and the camera and the RMS height (cm) and correlation length (cm) were also calculated and archived, which could be opened by Notepad or Microsoft Office Word. Those provide reliable reference for the roughness of the same land cover type. The gravimetric soil moisture (soil samples from 0-1cm, 1-3cm and 3-5cm) was measured by the microwave drying method. The file can be opened by Microsoft Office Word. The shallow layer soil moisture was measured by hydra prob from 12:00 to 17:00 on 14 and by the Hydra probe (straight downward for 0-5cm) and HH2 (level into the soil surface) on 16. The surface temperature was measured by the thermal resistor. The file can be opened by Microsoft Office Word. Four data files were included, the brightness temperature, the surface temperature, the soil moisture and the surface roughness.

2019-09-15

WATER: Dataset of surface roughness measurements in the Linze grassland foci experimental area on Jun , 2008

The dataset of surface roughness measurements was obtained in the reed plot A, the saline plots B and C of the Linze grassland foci experimental area on Jun. 7, 18 and 25, 2008. All the quadrates were divided into 4×4 subsites, with each one spanning a 120×120 m2 plot. With the roughness plate 110cm long and the measuring points distance 1cm, the samples were collected from south to north and from east to west, respectively. The coordinates of the sample would be got with the help of ArcView; and after geometric correction, surface height standard deviation (cm) and correlation length (cm) could be acquired based on the formula listed on pages 234-236, Microwave Remote Sensing, Vol. II. The original photos of each sampling point, surface height standard deviation (cm) and correlation length (cm) were included this dataset. The roughness data were initialized with the sample name, which was followed by the serial number, the name of the file, standard deviation and correlation length. Each .txt file is matched with one sample photo and standard deviation and correlation length represent the roughness. In addition, the length of 101 needles is also included for further checking.

2019-09-13

WATER: Dataset of ground truth measurement synchronizing with PROBA CHRIS in the A'rou foci experimental area on Jun. 23, 2008

The dataset of ground truth measurement synchronizing with PROBA CHRIS was obtained in No. 2 and 3 quadrates of the A'rou foci experimental area on Jun. 23, 2008. Observation items included: (1) quadrates investigation including GPS by GARMIN GPS 76, plant species by manual cognition, the plant number by manual work, the height by the measuring tape repeated 4-5 times, phenology by manual work, the coverage by manual work (compartmentalizing 0.5m×0.5m into 100 to see the percentage the stellera takes) and the chlorophyll content by SPAD 502. Data were archived in Excel format. (2) roughness by the self-made roughness board and the camera. The processed data were archived as .txt files. (3) BRDF by ASD FieldSpec (350~2 500 nm), with 20% reference board and the observation platform made by Beijing Normal University. The processed reflectance and transmittivity were archived as .txt files. (4) LAI of stellera and pasture by the fisheye camera (CANON EOS40D with a lens of EF15/28), shooting straight downwards, with exceptions of higher plants, which were shot upwards. Data included original photos (.JPG) and those processed by can_eye5.0 (in Excel). For more details, see Readme file. Five files were included, spectrum in No.2 quadrate, multiangle observations in No.2 and 3 quadrates, roughness photos in No.2 and 3 quadrates, the fisheye camera observations, and the No.2 and 3 quadrates investigation.

2019-09-12

Lithology of the deep sediment core in the midstream of the Heihe River Basin

A total of 500 meters of core (including supplemented samples) was obtained in the 550-meter deep drilling,which was carried out in Minghua Township along the midstream of Heihei River, from June to December 2013. The core of the borehole rock was cut and sampled, and the lithology characteristics of the borehole were primarily obtained.

2019-09-12

WATER: Dataset of survey at the poplar sampling plot at Linze station foci experimental area (2008.06)

The dataset of survey at the poplar sampling plot was obtained in the Linze station foci experimental area. Observation items included: (1) soil profile moisture and temperature (0-5cm, 0-5cm, 10-20cm, 20-40cm and 40-60cm) with photos measured twice by the cutting ring method (50cm^3, each layer), once by ML2X Soil Moisture Tachometer and the probe thermometer (15cm, twice each layer) on Jun. 3, 2008. Data were archived as Excel files. (2) shallow layer soil moisture (0-5cm) measured once by the cutting ring method (50cm^3, once each point) and twice by ML2X Soil Moisture Tachometer on Jun. 4, 2008. 13 points were selected and data were archived as Excel files. (3) LAI by TRAC on Jul. 20, 2008. Data were archived as Excel files. (4) roughness measured by the roughness plate together with the digital camera. 18 points were selected and data were archived in JPG format format. (5) forest investigation of Populus gansuensis from Jun. 5-13, 2008: coordinates, the diameter at breast height and the crown size by the measuring tape, full height by TruPulse200. 408 trees were selected and data were archived as Excel files. See the metadata record “WATER: Dataset of setting of the sampling plots and stripes in the Linze station foci experimental area” for more information of the quadrate locations.

2019-09-12