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Researchers have identified unique salt chimneys on the Dead Sea floor.

Key facts about the Dead Sea:

	Details
Location	• Located between Jordan and Israel, with the eastern shore in Jordan and the western shore in Israel. • The southern half of the western shore belongs to Israel, and the northern half is in the West Bank. • Divided by Al-Lisan peninsula into two basins: the northern basin is deep (400 m), and the southern basin is shallow (< 3 m).
Geographical Features	• 430.5 meters below sea level, the Earth’s lowest land-based feature. • Length: 50 km, Width: 15 km at its widest point. • Surrounded by the Judaea hills (west) and Transjordanian plateaus (east).
Salinity and Density	• Salinity: 34.2%, almost ten times saltier than ordinary seawater, making it the fourth saltiest water body in the world. • Density: 1.240 kg/L, which allows people to float easily.
Inlets and Outlets	• Main inlet: Jordan River. • No outlet, water loss occurs primarily through evaporation. • High salinity and harsh climate result in no life except for algae and microorganisms.

Salt chimneys are tall, chimney-like structures made of crystallized salt, recently discovered on the Dead Sea floor.
They are found by researchers from the Helmholtz Centre for Environmental Research (UFZ) during an underwater survey.
These chimneys range from 1 to over 7m in height.
Formation Process:
- Groundwater from surrounding aquifers flows through old salt deposits around the Dead Sea basin, dissolving halite (salt) and carrying it as brine.
- Despite being saline, the brine is less dense than the Dead Sea water due to its high salinity, causing it to rise as a plume from the lake bed.
- When this brine contacts the colder Dead Sea water, it rapidly crystallizes, forming chimney structures that can grow several centimeters in height each day.

Thousands of sinkholes have appeared near the Dead Sea in recent decades; understanding chimney formation may aid in preventing future collapses in vulnerable areas.
Researchers have linked the formation of salt chimneys to underground cavities, which are often the precursors to sinkholes.
The location of these chimneys may help predict areas at high risk for sinkhole formation, offering a way to monitor and mitigate potential hazards.

[2018] Which of the following has/have shrunk immensely/dried up in the recent past due to human activities?

1. Aral Sea

2. Black Sea

3. Lake Baikal

Select the correct answer using the code given below:

(a) 1 only

(b) 2 and 3

(d) 1 and 3